Penerimaan inang dan efisiensi pakan oleh Epilachna vigintioctopunctata pada beberapa tanaman inang
HOST ACCEPTANCE AND FOOD EFFICIENCY BY
EPILACHNA VIGINTIOCTOPUNCTATA ON SEVERAL HOST
PLANTS
HACHIB MOHAMMAD TUSAR
GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2013
DECLARATION
With due respect I hereby declare that this thesis “Host Acceptance and Food
Efficiency by Epilachna vigintioctopunctata on Several Host plants” is my own
work under the supervision of an advisory committee. It has not yet been
presented in any form in any educational institution. The sources of information
which is published or not yet published by other researchers have been mentioned
and listed in the reference of this thesis.
Bogor, January 2013
Hachib Mohammad Tusar
Reg. No. A351108061
ABSTRAK
HACHIB MOHAMMAD TUSAR. Penerimaan Inang dan Efisiensi Pakan oleh
Epilachna vigintioctopunctata pada Beberapa Tanaman Inang. Dibimbing oleh
ENDANG SRI RATNA dan TEGUH SANTOSO.
Epilachna vigintioctopunctata (Fabricius) (Coleoptera: Coccinellidae)
umumnya dikenal sebagai kumbang Hadda. Serangga ini bersifat fitofag dan dapat
menjadi hama utama serta menimbulkan kerusakan yang sangat berarti pada
tanaman Solanaceae. Kesesuaian hama dan tanaman inang tertentu dapat
mempengaruhi aktivitas makan dan kecernaan makanan yang mendukung
pertumbuhan dan perkembangan serangga. Hingga saat ini belum ada laporan
mengenai penerimaan dan kesesuaian pakan pada beberapa jenis tanaman inang
oleh E. vigintioctopunctata di Indonesia. Tujuan penelitian ini adalah menentukan
penerimaan inang dan mengukur efisiensi pakan oleh E. vigintioctopunctata pada
beberapa jenis tanaman. Larva dan imago E. vigintioctopunctata mengerigiti dan
menelan daun pakan Solanum melongena, S. tuberosum, Lycopersicon
esculentum, Physalis angulata, Cucumis sativus, dan Cucurbita pepo sebagai
tanaman inang. Larva dan imago paling banyak memakan daun S. melongena
seluas 6.75 dan 1.771 cm2/serangga/hari, diikuti oleh L. esculentum 4.42 dan 1.35
cm2/serangga/hari. Rata-rata daun L. esculentum yang dimakan oleh larva instar
empat awal sebesar 1.5 x 105 µg/serangga/hari lebih tinggi dari S. melongena
1.0 x 105 µg/serangga/hari. Sebaliknya, tingkat pertumbuhan rata-rata dan
efisiensi konversi pakan yang dicerna oleh larva berturut-turut sebesar
3723.7 µg/serangga/hari dan 43.17% pada daun S. melongena lebih tinggi
dibandingkan L. esculentum sebesar 2984.8 µg/serangga/hari dan 19.94%. Tingkat
konsumsi kumbang E. vigintioctopunctata pada S. melongena rendah namun
memiliki efisiensi cerna pakan yang tinggi.
Kata kunci: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, efisiensi konversi pakan, interaksi tanaman inang.
ABSTRACT
HACHIB MOHAMMAD TUSAR. Host Acceptance and Food Efficiency by
Epilachna vigintioctopunctata on Several Host Plants. Supervised by ENDANG
SRI RATNA and TEGUH SANTOSO.
Epilachna vigintioctopunctata (Fabricius) (Coleoptera: Coccinellidae) is
commonly known as hadda beetle. This insect is a phytophagous and causes a
serious pest and built a tremendous damage to solanaceaeous crops. The
suitability of a certain host plant could affect on feeding activity and digestibility
of food that support insect growth and development. Recently, food acceptance
and suitability on several varieties of host plants by E. vigintioctopunctata has not
been reported in Indonesia. The objective of this research was to investigate the
host acceptance and food efficiency by E. vigintioctopunctata on several host
plants. Both larvae and adults bite on six species of leaves Solanum melongena,
S. tuberosum, Lycopersicon esculentum, Physalis angulata, Cucumis sativus, and
Cucurbita pepo. The larvae and adult beetles mostly fed on S. melongena with the
areal leaf consumed 6.75 and 1.771 cm2/insect/day, followed by L. esculentum,
4.416 and 1.35 cm2/insect/day. The average rate of consumption on L. esculentum
by early 4th instar larvae was 1.5 x 105 µg/insect/day higher than S. melongena
was 1.0 x 105 µg/insect/day. On the other hand, the average growth rate and
efficiency of conversion of digested food were 3723.7 µg/insect/day and 43.17%
higher than in S. melongena than L. esculentum were 2984.8 µg/insect/day and
19.94% respectively. This beetle has low consumption but high efficiency of
utilization food on S. melongena.
Key words: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, food conversion efficiency, host plant interaction.
SUMMARY
HACHIB MOHAMMAD TUSAR. Host Acceptance and Food Efficiency by
Epilachna vigintioctopunctata on Several Host Plants. Supervised by ENDANG
SRI RATNA and TEGUH SANTOSO.
Epilachna beetle (Epilachna vigintioctopunctata Fabr.) (Family
Coccinellidae. Order: Coleoptera) is very important pest in Asia that commonly
attacks solanaceous plants. Both larvae and adults feed by scrapping the epidermal
tissues and built a characteristic skeletonized pattern on remaining leaves. The
affected leaves will dry and drop lead to reduce the bearing of the plants. In a high
population, this insect may damage up to 80%, even complete defoliation can
occur, resulting in total crop failure 10-20% yield loss in aubergine. The
suitability of a certain host plant might affect on feeding activity and digestibility
of food that support growth and development. The research is conducted to
investigate the host acceptance and food efficiency by Epilachna
vigintioctopunctata on several host plants.
This study showed that six species of Solanum melongena, Lycopersicon
esculentum, Solanum tuberosum, Physalis angulata, Cucumis sativus, Cucurbita
pepo were accepted as a fed for E. vigintioctopunctata out from 12 treated leaves
of Solanaceous, Cucurbitaeus and Legumineous plants. Between those six types
of food, the highest feeding area caused by larvae and adult was found on
S. melongena leaf 6.75 and 1.771 cm2/insect/day, respectively. The average rate of
consumption leaf L. esculentum by early 4th instar larvae was 1.5 x 105
µg/insect/day higher than S. melongena is 1.0 x 105 µg/insect/day respectively. On
the other hand, all food efficiency parameters above on late 4th instar larvae were
not significantly different found in both S. melongena and L. esculentum.
The outcome of this research will supply a basic knowledge of feeding
behavior, damaging host plant and a potency of growth and development of
insect. The result could support a complementary approach in integrated pest
management (IPM) program to reduce the extent of losses caused by
E.vigintioctopunctata.
Key words: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, food conversion efficiency, host plant interaction.
Copyright© 2013 Bogor Agricultural University
Copyright are protected by law
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doesn’t inflict the name and honor of Bogor Agricultural University.
It is prohibited to republish and reproduce all or part of this thesis without the
permission of Bogor Agricultural University.
HOST ACCEPTANCE AND FOOD EFFICIENCY BY
EPILACHNA VIGINTIOCTOPUNCTATA ON SEVERAL HOST
PLANTS
HACHIB MOHAMMAD TUSAR
Thesis
as a part of the requirements for acheiving the degree of
Master of Science in Entomology at
the Department of Plant Protection
GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2013
Thesis External Examiner: Prof Dr Dadang, MSc.
Title of Thesis
:
Name
Registration number
:
:
Host Acceptance and Food Efficiency by Epilachna
vigintioctopunctata on Several Host Plants
Hachib Mohammad Tusar
A351108061
Approved by
Advisory Committee
Endang Sri Ratna, Ph.D.
Chairperson
Teguh Santoso, Ph.D.
Member
Agreed by
Head of the Program Study Entomolgy
Dean of Graduate School
Dr. Pudjianto, M.Si.
Dr. Dahrul Syah, M.Sc.Agr.
Date of Examination: 23 January 2013
Date of Completion:
ACKNOWLEDGEMENT
My first and foremost earnest gratitude to ALLAH SWT for blessing me
and gave me the ability to complete this study. Several people in one or another
way were contributed for the success of this work. I would like to convey my
sincere and special thanks to my main supervisor Dr. Endang Sri Ratna for her
guidance, encouragement, advice and constructive criticisms during the
preparation, laboratory analysis and finalizing this thesis. I also thankful to her for
allowing me to use her materials for conducting my research; otherwise this work
would not be completed in time.
I am also thankful to my second supervisor Dr. Teguh Santoso for his
valuable time and comments on this work. I am very much grateful to the
Ministry of National Education, Republic of Indonesian for giving me the
opportunity to do a Master of Science in Entomology from this prestigious Bogor
Agricultural University under the Developing Countries Partnership Scholarship
Program (DCPS).
I acknowledge to Dr. Pudjianto, M.Si. coordinator of major Entomology and
Djoko Prijono M.Agr.Sc. Lecturer, Research Methodology, IPB for their guidance
and encouragement throughout my study period. Special thanks also go to the
following people:
1.
The technicians and staff in the laboratory of Insect Physiology and
Toxicology at the Department of Plant Protection, who were always help
me. I am very much thankful to my Indonesian friends Herma Amalia
(Lecturer, IPB), Adeel ABD Alkarim Fadhl (Lecturer, Sana University,
Yemen), Maroning Useng (Lecturer, Yala Islamic University, Thailand) and
my Bangladeshi friends living in Indonesia: Md. Kamruzzaman (University
Padjadjaran, Bandung), Md. Shohel Rana (Gadjah Mada University,
Yogjakarta).
2.
My Bangladeshi teachers Prof. Md. Hamidur Rahman (Dept of Entomology,
PSTU), Prof. Dr. Md. Mohsin Hossain Khan (Dept of Entomology, PSTU),
Prof. Dr. Habibur Rahman (Dept of Entomology, PSTU), Dr. Mohammad
Atikur Rahman (Associate Prof. Dept of Entomology, PSTU),
Dr. Md. Hemayet Jahan (Associate Prof. Dept of Entomology, PSTU),
my friends A.B.M Mahbub Morshed Khan (Asst. Prof. Dept of Agricultural
Botany, PSTU), Liton Sen (Lecturer, PSTU), Arifur Rahman Noman (AFS,
PSTU), Rahat Mahmood (AFS, PSTU) and Zead Hassan (Upazilla
Secondary Education Officer) for their contribution on counseling and
moral support during the entire academic period.
Special thanks to my parents, my wife, my brothers, sister and my relatives
for their continued prayer.
Bogor, January 2013
Hachib Mohammad Tusar
CURRICULUM VITAE
The writer was born on 17th October 1982. His father Md. Quaum
Howlader and mother Aktarunnessa in Village: Jangalia, Post: Aorabunia, Thana:
Kathalia, District: Jhalakati. The writer is the first son in the family of four
children and was married on 20 August 2010 having one child. In 1997 the writer
achieved Secondary School certificate degree from Aorabunia Model High School
in Bangladesh. In 1999 he achieved Higher Secondary School Certificate from
Amrita lal Dey College and in 2000 he was admitted in Patuakhali Science and
Technology University under the faculty of Agriculture and was graduated with
bachelor of science in Agriculture degree in 2006. In 2007 the writer was getting
job at Patuakhali Science and Technology University, Bangladesh. In 2009, the
writer was get the opportunity to do a three years (With one year Bahasa
Indonesia Language course) Master of Science degree in Entomology at the
department of Plant Protection in Bogor Agricultural University, Bogor, Indonesia
under developing countries partnership scholarship program offered by the
Ministry of National Education, Government of Peoples of Republic of Indonesia.
CONTENTS
LIST OF TABLES
xii
LIST OF FIGURES
xii
INTRODUCTION
Background
Objectives of this Research
1
1
2
LITERATURE REVIEW
Biology of Epilachna vigintioctopunctata
Host Plant Interaction
Importance of Solanum melongena
Importance of Lycopersicon esculentum
Food Conversion Efficiency
3
4
5
6
7
MATERIALS AND METHODS
Time and Place of Research
Materials
Preparation of Plants
Preparation of Insects
Food Acceptance Test
Feeding Area Measurement
Food Efficiency Test
Data Analysis
8
8
8
8
9
10
10
11
RESULT AND DISCUSSION
Food Acceptance
Leaf Areal Damage
Food Efficiency
13
14
15
CONCLUSION AND RECOMMENDATION
17
REFERENCES
18
LIST OF TABLES
1 Percentage of feeding on tested host plants
2 The effects of two types of food on the rate of consumption, growth
rate and efficiency of utilization of food by early fourth instar larvae
E. vigintioctopunctata
3 The effects of two types of food on the rate of consumption, growth
rate and efficiency of utilization of food by late fourth instar larvae
E. vigintioctopunctata
13
16
16
LIST OF FIGURES
Rearing of E. viginctioctopunctata in the Laboratory
Acceptance test of E. viginctioctopunctata on twelve types of food
Measurement of feeding area of leaves
Efficiency test by using larvae E. viginctioctopunctata on S. melongena
and L. esculentum leaves
5 Feeding consumption by larvae and adult of E. vigintioctopunctata on
several host plant
1
2
3
4
9
9
10
12
14
INTRODUCTION
Background
Epilachna vigintioctopuncata (Fabricius) called hadda beetle is a somber
pest of important Solanaceaous crops such as aubergine, potatoes, tomatoes and
bitter gourds (Alam 1969; Richards and Filewood 1988). This pest can also attack
cucurbitaceous and leguminaceous crops (Imura and Ninomiya 1978). The
population of this beetle is distributed over an extensive geographical area such as
India, Pakistan, China, Japan, South East Asia, and Oceania (Katakura et al.
1988). This hadda beetle has four generation per year. In general, the peak
population is found from July to August (Kalshoven 1981). In Indonesia, the
larval population increased rapidly in November and caused seriously damage at
the end of December. Both larvae and adults feed on the leaves by scrapping the
epidermal tissue to form skeletonized pattern “windows like” that is a typical
hadda beetle scrapping (Imura and Ninomiya 1978). Further devastation shows
drying and dropping of the leaves leads to harshly distressed growth and yield of
the plant (Alam 1969). In a very high population, it evoked complete defoliation
resulting in a total crop failure (Rajagopal and Triveldi 1989). The damaging
plants could reach up to 80%. Alam (1969) reported that this beetle cause 10-20%
yield loss of aubergine.
Nutrients are substances that are necessary for growth, maintaining tissue,
reproduction, and supply energy for the organism. Most of the nutrients derived
from consumed food. Nutrients required by insects should be in balanced
proportion, if insects do not get nutritional balance so the insects growth, molting
and egg laying will be failured (Chapman, 1998). Nation (2001) mention that
nutrients such as carbohydrates, proteins, fats, sterols, vitamins, nucleic acids,
water and minerals are required by insects. Food becomes the cornerstone of
efforts to meet the nutrients that will support the growth and development of the
insects. The higher efficiency of utilization of food shows the higher quality of the
nutrients present in food (Schoonhoven et al. 1998).
According to Kogan (1982), in terms of the suitability of the host plant, the
nutritional value of food shows whether or not the food support physiological
processes related to growth and development of the larvae. Insect behavior in
accepting or rejecting food type can be affected by the chemicals contained in the
plant. Primary chemicals are parts of plants that used for growth or development
of insects, while secondary chemical has function for rejection (repellent),
inhibition of eating (antifeedant), attractants, or a deterrent.
The food that has been digested is to be used for growth and development,
while undigested food will be passed through the intestinal lumen in the form of
feces. Insect will choose the favorable food for maintaining survival of the fittest.
The quality and quantity of food plays a vital role on growth, development and
reproduction of insect (Maurice and Kumar 2012, Scriber and Slansky 1981).
Host acceptance and food efficiency by E. vigintioctopunctata has not yet been
done in Indonesia and for this reason this topic was selected for research.
According to Waldbauer (1968) there are three parameters for the efficiency of
utilization of food that is approximate digestibility (AD), efficiency of conversion
of digested food (ECD), and the efficiency of conversion of ingested food (ECI).
2
This research supplied an effective complementary approach in integrated
pest management (IPM) to reduce the extent of losses caused by
E. vigintioctopunctata. IPM looks for the weak links in the pest’s biology and
behavior (life cycle, food and habitat preferences and sources, how it feeds, mates,
reproduces, and disperses). These weaknesses are then exploited to manage the
pest by altering or removing one or more of the basic necessities.
Objectives
The objective of this research was to study host acceptance and food
efficiency by E. vigintioctopunctataon on several host plants.
3
LITERATURE REVIEW
Biology of Epilachna vigintioctopunctata
Epilachna vigintioctopunctata (Fabricius) has another synonym that is
Henosepilachna vigintioctopunctata (Evans 2012). The taxonomy of this species
remains confusing throughout history because of its wide variation in external
appearance. In Pakistan, this species has been called E. sparsa (Naz et al. 2012).
Hadda beetle E. vigintioctopunctata is polyphagous and a serious pest of
Solanaceous crops such as aubergine, potato, tomato over a wide range from
Japan to South Asia and Australia. In Bangladesh, a group of Solanaceae,
Cucurbitaceae and Leguminoceae crops were attacked by this insect (Alam 1969).
Moreover, it is as recorded pest of cucurbitaceous crops in India. In Pakistan,
E. vigintioctopunctata can be found with varying degree of population densities in
all the areas where the host plants are grown (Naz et al. 2012).
Adults are typically ladybird shaped. They are 5-8 mm long, convex
dorsally, flattened ventrally and the head is partly hidden beneath the pronotum.
Legs and antennae are relatively short. The upper surface is covered with fine,
short hairs. Tarsi are composed of four segments. The second segment from the
base is strongly lobed underneath, while the third segment is very short and small,
and is the same width as the base of the claw-bearing fourth segment (Fabricius
2000). E. vigintioctopunctata has a typical angled of elytral apex. First coxal line
is subcomplete. Elytral spots vary between 12 and 28. There are two species one
having 12 spots, Epilachna 12-stigma and another having as many as 28 spots,
Epilachna 28-punctata (Anonym 2012). Exact diagnosis can be made by
examining male genitalia with a well developed basal knife edge and apical thorn
on median lobe, siphonal tip tapering on one side. The female genitalia have a
deep notch on inner edge. The male genitalia, the median lobe has a basal knife
edge beginning at the foot of paramera and a buldge beyond the middle, after
which it curves up into an apical hook. Paramera with an apical thorn and covered
with hairs shorter than those of median lobe. Siphon gently curved near the base,
then straight, ending in a point. The female genital plates has an excavation on the
underside with a sharp dark edge toward apex. In the male, the hind margin of the
sixth visible sternite is concave; in the female. It has a deep median split. The
tarsal claws each have three distinct teeth, the basal tooth is subrectangular
(Fabricius 2000).The pronotum presents variable maculation (Naz et al. 2012).
The ovoid elytra are broadest in the anterior quarter, and strongly convex,
without broadly explanate lateral margins. The sutural angle has a very weak
tooth and is not entirely evenly rounded. The ground colour is brownish-yellow to
dark brown, with 6-14 black spots on each elytron and seven on the pronotum.
Newly emerged adults are entirely yellow, but as the body hardens, dark spots
develop over 6-12 hours. Antennae are moderate in length; longer than the width
of the frons, but shorter than the head width; the last three segments forming an
asymmetrical club. The anterior angles of the pronotum are produced anteriorly,
and are strongly rounded externally. The punctation of the head and pronotum is
close, with shining intervals. The punctation of the elytra is double, with very
fine, close-set punctures. The postcoxal plates on the first visible sternite of the
4
abdomen are rounded, do not reach the hind margin of the segment, and are
incomplete externally (Fabricius 2000).
Eggs are yellow, elongate, oval and usually laid on the under surface of a
leaf in small batches of 5-40. The eggs are attached on the upper side of the leaf
surface by a short stalk at its base. The egg is slightly broader basally than
apically gave its length as 1.1 mm and its width as 0.4 mm. Larva have the
appearance of the typical ladybird larva. The larval body has elongate and
elliptical shaped with moderately long legs and a well-developed head and
mandibles. The body is covered with long branched processes bearing spines.
There are four larval instars. The final-instar larva is about 6 mm long and 2.8 mm
wide across the third abdominal segment. It is generally has pale yellow colour,
although the more sclerotized parts and areas around the base of the scoli are
brown.
The pupa of E. vigintioctopunctata is white initially, turning yellow later,
with brown spots appearing on the dorsal surface. Its size was 4.6 mm long and
3.7 mm wide. The pupal period lasts about 4 days (Fabricius 2000).
E. vigintioctopunctata is found active from April to middle of October and
highest population was recorded (8.14 beetles/plant) during middle of September
in Terai region, India. Population of this beetle showed significant positive
correlation with average temperature, relative humidity and weekly rainfall.
Duration of life cycle shortest (26.71 days) in June-July and longest (33.52 days)
in September-October. Highest fecundity (272.32 eggs) is recorded during MarchApril. Life cycle and fecundity is negatively and positively correlated with
temperature and relative humidity respectively. High temperature and humidity
during July to September decreased the duration of life cycle and increased
fecundity leading into rapid multiplication of pest resulting higher population
level and there by crop loss during the period (Ghosh et al. 2001).
Hadda beetle feeds actively in the morning and evening hours and feeding
declines rapidly in the middle of the day and after midnight. The daily fluctuation
in the rate of feeding depends mainly on the temperature which determined the
level of metabolism (Tilavov 1981).
Host-Plant interaction
Three optical characteristics of plants may influence host selection behavior
that is spectral quality, dimensions (size), and pattern (shape). In the process of
host-plant selection, two main consecutive phases are searching and contacttesting. The first phase may end with the event of finding; the second phase ends
with acceptance or rejection. Acceptance is a crucial behavioral decision as it
results in ingestion of plant materials. Standardized host-plant selection sequences
are (1) the insect has no physical contact with a plant and either rests or moves
about randomly, walking or flying. (2) It perceives plant-derived cues, optical
and/or olfactory. (3) It responds to these cues in such a way that the distance
between its body and the plant decreases. (4) The plant is found, i.e. it is contacted
by either touching or climbing it, or by landing on it. (5) The plant surface is
examined by contact-testing. (6) The plant may be damaged and the content of
tissues released by nibbling or test-biting (in the case of biting-chewing species),
probing (piercing-sucking species), or puncturing with the ovipositor. (7) The
plant is accepted or is rejected, resulting in the insect’s departure. During each of
5
these steps the insect may decide to turn away from the plant before contacting it,
or to leave it after contact (Schoonhoven et al. 2005).
Upon contact with the plant an insect obtains additional information on
plant quality through tactile (mechanosensory) and contact chemosensory (taste or
gustatory) stimuli. Physical features of plant organs or tissues can profoundly
influence host-plant selection behaviour. Acceptance of the plant depends upon
the nature of the sensory input elicited from appropriate receptors at each relevant
stage in this host finding process. The complex patterns created by positive and
negative sensory inputs that produce behavioral responses are the result of neural
integration which probably occurs within decision-making centers in the higher
central nervous system (CNS). Each plant contacted will induce a certain level of
excitation, and in that way can be assigned a rank order of preference to an insect,
but the level of excitation will be dependent upon factors influencing the plant
such as seasonal effects, plant quality and induced plant defenses (Withers 1997).
Host finding behavior will change with an insect physiological condition (such as
nutritional state, oocyte dynamics, age and stage of development (Barton 1993).
The presence of trichomes and wax crystal structures on the plant surface, leaf
thickness and toughness, sclerotization, and high silica content may cause
avoidance behavior, and such plant traits are assumed to often fulfill a defensive
function (Schoonhoven et al. 2005).
Importance of Solanum melongena
Aubergine (Solanum melongena), is an easily cultivated plant belonging to
the family Solanaceae. Its fruit is high in nutrition and commonly consumed as a
vegetable. The fruit and other parts of the plant are used in traditional medicine.
Aubergine fruits can also be pureed, flavoured, and used as a dip or chutney that
is popular in Mediterranean and Indian cuisine. In indian cuisine, they are used in
curries and even made into soufflés. In traditional chinese medicine, all parts of
the plant can be used to stop intestinal bleeding. The fruit of the plant is used as an
antidote in cases of mushroom poisoning. In indochina, parts of the plant are used
as a purgative. For traditional malay medicine, the ashes of the fruit are used in
dry, hot poultices to treat haemorrhoids. To treat ulcers, the root is pounded and
applied inside the nostrils (Thulaja 2012). In particular the fruit helps to lower
blood cholesterol levels and is suitable as part of a diet to help regulate high blood
pressure. It is also used as an antidote to poisonous mushrooms. It is bruised with
vinegar and used as a poultice for cracked nipples, abscesses and haemorrhoids.
The leaves are narcotic. A soothing and emollient poultice for the treatment of
burns, abscesses, cold sores and similar conditions can be made from the leaves.
Aubergine leaves are toxic and should only be used externally. The ashes of the
peduncle are used in the treatment of intestinal haemorrhages, piles and toothache
(Anonym 2012).
The fruit should not be eaten raw. It can be baked, stewed or added to soups,
curries etc. The fruit is said to be very nutritious. It is a good source of vitamin C
and potassium. The fruit can be up to 20 cm long in cultivated plants (Anonym
2012). The aubergine is used mainly as a food crop. Solanum melongena is a
perennial growing to 1 m. The flowering season occured from July to September,
and the seeds ripen from August to October. The flowers are hermaphrodite and
are pollinated by Insects. (Anonym 2012).
6
Aubergine is one of the most common and popular vegetable crops
cultivated in Bangladesh. It is grown year-round having two major growing
seasons such as summer and winter. Aubergine is one of the rare vegetables,
which can be grown also in summer. It covers an area of 74,711 acres, which is
about 15% of total vegetable areas of the country. Although the crop is grown
throughout the country, it is intensively and commercially grown in Jessore,
Narsinghdi, Dhaka, Comilla and Bogra districts. Its annual production is about
191,525 metric tons with an average yield of 2.56 metric tons per acre. One of the
major factors of low yield of aubergine is insect pest such as aubergine shoot and
fruit borers, leafhoppers and Hadda beetles that causes serious damage to the crop
(Rahman 2009).
Aubergine is a relatively easy to cultivate and high-yielding vegetable with
a reasonable nutritional value. It should be possible to breed into aubergine
resistance for the more destructive pest and diseases which occur in the tropics.
This vegetable is in increasing demand in more affluent countries and are good
prospects for export from the tropics and subtropics (CAB 2007).
Importance of Lycopersicon esculentum
Information about the exact date for the first time growing tomatoes is not
specified, the tomato was grown in about 500 years before Christ. This plant is
native to South America and Central America. During the Spanish colonial period
tomato was transferred to other parts of the world i.e. Peru in the sixteenth century
and seventeenth-century England and reached to the Netherland. In the early
nineteenth century, tomatoes were distributed in the Middle East. Tomato is used
as one of the cooking materials. Now a days thousands of (near 7500) tomato
varieties are grown throughout the world. Consumption of tomato as a vegetable
began since the nineteenth century. According to global statistics 2008, about 130
million tons of tomatoes were produced in the world. China, America, Turkey,
India, Italy, Egypt and Iran were the largest producer of tomatoes (Mohammad
2011).
Lycopersicon esculentum is an annual growing crops. It is in flower from
Jun to September, and the seeds ripen from August to October. The flowers are
hermaphrodite and are pollinated by insects, self. L. esculentum can be used as a
savoury vegetable or flavouring in cooked foods, or can be eaten out of hand as a
dessert fruit. It is much used in salads and as a flavouring in soups and other
cooked foods. A juice made from the fruit is often sold in health food shops. The
fruit can also be dried and ground into a powder that can be used as a flavouring
and thickening agent in soups, breads, pancakes etc. An edible oil is obtained
from the seed. It is suitable for culinary purposes (Anonym 2012).
The pulped fruit is an extremely beneficial skin-wash for people with oily
skin. Sliced fruits are a quick and easy first aid treatment for burns, scalds and
sunburn. A decoction of the root is ingested in the treatment of toothache. The
skin of tomato fruits is a good source of lycopine, a substance that has been shown
to protect people from heart attacks. It seems to be more effective when it is
cooked and food products such as tomato ketchup and tinned tomatoes can be
obtained from tomato. Lycopine has also been shown to have a very beneficial
effects upon the prostate and is being used increasingly to treat enlarge prostate
7
and the difficulties in urination. A homeopathic remedy is made from the plant. It
is used in the treatment of rheumatism and severe headaches (Anonym 2012).
Food conversion efficiency
Food conversion efficiencies may vary considerably within a species. One
cause of such variation involves homeostatic (The ability or tendency of an
organism or cell to maintain internal equilibrium by adjusting its physiological
processes) adjustment of consumption rates and efficiency parameters such that an
insect can approach its ideal growth rate even with foods of different quality in
various environments. For example, insects that experience reduced ECDs due to
increased respiratory costs may be able to compensate by increasing consumption
rates or digestion efficiencies (ADs). Not all changes are homeostatic, however.
For instance, many insects increase food consumption rates in response to low
concentrations of critical nutrients such as protein. Other nonhomeostatic changes
in efficiency values may occur in response to plant allelochemicals. For example,
compensatory feeding to increase intake of a limiting nutrient may simultaneously
increase exposure to plant toxins, which in turn may reduce ECDs.
Intraspecific variation in food conversion efficiencies may also be related to insect
development (Lindroth 1993).
Food conversion efficiencies also vary greatly among species and this
variation is more closely related to feeding guilds than to taxonomic affinity. The
insects that feed on nitrogen-rich foliage generally have higher consumption rates
and assimilation efficiencies than do insects that feed on nitrogen-poor foliage,
and as a consequence grow and develop much faster. The relatively poor
nutritional quality of tree foliage has had important consequences for insect life
histories. In temperate regions forb feeders often have many more generations per
year than do tree feeders. Among tree-feeders, numerous species have adapted to
emerge and feed only on the especially nutritious early spring foliage, and thus
have only one generation per year. Growth rates are low due to low consumption
rates and low ECDs. Low ECDs may result from a requirement of these insects to
metabolize digested food in order to produce water (Lindroth 1993).
8
MATERIALS AND METHODS
Time and Place of Research
All experiments were conducted in the laboratory of Insect Physiology and
Toxicology, Bogor Agricultural University from June 2012 to November 2012.
Materials
The materials that were used for this experiment were leaves of Solanum
melongena, Solanum tuberosum, Lycopersicon esculentum, Physalis angulata,
Cucumis sativus, Cucurbita pepo, Momordica charantia, Vigna angularis,Vigna
sesquipedalis, Vicia faba, Sechium edule, Lagenaria leucantha, Plastic cylinder,
Larvae and adults of E. vigintioctopunctata, Electronic balance (GR 150, AND
Company limited, Japan), Leaf area meter (CI-202, product of CID, INC. USA),
etc.
Methods
Preparation of Plants
Twelve host plants S. melongena, S. tuberosum, L. esculentum, P. angulata,
C. sativus, C. pepo, M. charantia, V. angularis, V. sesquipedalis, V. faba, S. edule,
and L. leucantha were used in this study. The leaves conducted for acceptance and
feeding area measurement test were picked up from the farmer organic field
surrounding Bogor area, while the leaves conducted for efficiency test was
collected from growing plant in the laboratory.
Two plant species used for the efficiency test were aubergine (S.
melongena) and tomato (L. esculentum). Seeds were supplied from the market and
singly planted in a polythene (10 cm in diameter and 20 cm in depth) with soil
media. The plants were maintained with insecticide-free. The leaves used for the
experiment were about two months aged when they had approximately 5-10 true
leaves.
Preparation of Insects
Beetle was previously identified according to the reference from insect
standard collection that is available in the museum of Insect Biosystematic
Laboratory and books (Kalshoven 1981; CSIRO 1991). Two sources of beetle E.
viginctioctopunctata were carried out in this study. The beetles used for
acceptance test were collected from the agricultural fields neighboring Bogor
Agricultural University area and the beetles used for feeding area measurement
and food efficiency tests were provided from laboratory mass rearing insect.
The maintaining of the insect stock culture was conducted in the laboratory
of Insect Physiology and Toxicology, Bogor Agricultural University under
temperature between 26-28oC and 85-87% relative humidity.
Adult beetles were collected from the fields and were subsequently reared in
an aubergine plant. Mating pairs was parted and kept in plastic cylinder (7 cm in
diameter and 20 cm in height) contained aubergine leaves (Figure 1). The mated
females were allowed laying eggs and the hatched eggs were continuously
maintained until producing fourth instar larvae that were used for the experiment.
9
Figure 1 Rearing of E. viginctioctopunctata in the laboratory
Food Acceptance Test
Early fourth instars larvae and adult beetles were singly placed in a plastic
container which contains a sheet leaf with size 6 x 3 cm as a food treatment
(Figure 2). These beetles feeding behavior were observed in 5 days for twelve
types of plant and food were changed every 24 hrs and damage leaves caused by
feeding activity were collected. Each 10 replications were conducted to both
stages of beetles. The acceptable food was evaluated and the percent feeding on
total treatment was calculated. This experiment was conducted by using no choice
method described by Teparkum (2000).
Calculation has been down by using following formula:
Feeding on total replication (%) = total feeded replication x 100/ total replication
Figure 2 Acceptance test of E. viginctioctopunctata on twelve types of food
10
Feeding Area Measurement
Six species of plants S. melongena, S. tuberosum, L. esculentum,
P. angulata, C. sativus, and C. pepo resulted from a previous experiment were
used for feeding area measurement test. The method of introducing beetles to their
food was the same as described previously in food acceptance test. Each 10
replications were conducted to both stages of beetles. Observation has been done
for one day. Feeding areas was measured by using leaf area meter machine
(CI-202, CID, INC. USA) (Figure 3).
Figure 3 Measurement of feeding area of leaves
Efficiency Test
Two types of larvae were used for carried out this experiment that is early
fourth instars with the age of one day after molt and late fourth instars with the
age of three days after molt.
Determine of dry weight of leaves and larval proportion. Food
S. melongena and L. esculentum that was found as mostly fed from the previous
experiment was cut each of 10 pieces about the size of 6 x 3 cm. Then, the 10
pieces of leaves of each type was weighted initially (wet weight). After that 10
pieces of each type of leaf was wrapped separately into aluminum foil and then
put into the oven for 2 hours at 105 °C. After two hours, each envelope containing
single piece of leave was weighted (dry weight). If the weight after dry is marked
by y and initial weight or wet weight is marked by x, then proportion of dry
weight of leaves y/x which is necessary for calculating initial dry weight of leaves
to get food consumption rate (CR).
The initial weight of larvae was estimated using 20 larvae divided each by
10 feed on S. melongena and 10 on L. esculentum. Larvae were wrapped by
aluminum foil individually and put into the oven for 2 hours at 105 °C. After two
hours, dry weight larvae were measured. If the initial weight (wet) is given the
symbol (x) and dry weight symbol (y), then the proportion of dry weight of the
larvae is y/x which is necessary for calculating initial dry weight of larvae to get
growth rate (GR).
11
The utilization of food. To determine the utilization of food by the larvae,
the following work has been conducted.
A piece of leaf S. melongena and L. esculentum was cut into 6 x 3 cm in size
approximately then weighed separately. After that the cut leaf was placed into the
petri dish individually. One of fourth instar larva was weighted initially and then
placed into a petri dish and then closed. The larva was kept to feed for 24 hrs
(Figure 4). This treatment was repeated 10 times for each leaf and each stage of
larvae. All treatments were labeled in accordance with the treatment and
repetition.
After 24 hrs, the larvae were removed from petri dish. Each larva and the
remained leaf were wrapped separately by aluminum foil. Each has been labeled
based on treatment and repetition. Both samples of larvae and leaf were allowed
to dry within the oven for 2 hrs at 105 °C. All samples were removed from the
oven and kept in room temperature and then the sample was weighed individually.
In case of undetermined fecal larvae from this experiment, so the weight was
assumed zero. The measurements of efficiency parameter were calculated
according to the equation below:
1. CR = ΔC/PF
ΔC = IDWL – FDWL
CR
=
PF
=
IDWL =
FDWL =
2.
RCR
RCR = CR/AW
AW = IDWL + FDWL/2
Consumtion rate (µg/day)
Period of feeding
Initial dry weight of leaf
Final dry weight of leaf
= Relative consumption rate (µg
leaf / µg larvae/ day)
AW = Average weight of larvae
IDWL = Initial dry weight of larvae
FDWL = Final dry weight of larvae
3. GR = FDWL IDWL/PF
GR
= growth rate (µg/ day)
FDWL = Final dry weight of larvae
IDWL = Initial dry weight of larvae
4. RGR= GR/AW
RGR
= Relative growth rate (µg/µg
larvae/ day)
5. AD = ΔC- WF/ ΔC x100%
AD
WF
= Approximate digestibility (%)
= Weight of fecal larvae
6. ECI = GR/ CR x 100%
ECI
= Efficiency of conversion of
ingested food (%)
7. ECD = GR/ CR – WF x 100%
ECD
= Efficiency of conversion of
digested food (%)
Measurements has been done by using gravimetric method (Waldbauer 1968)
with t- test Microsoft excel at 5% level of significance.
12
Figure 4 Efficiency test by using larvae of E. viginctioctopunctata on
S. melongena and L. esculentum leaves
13
RESULT AND DISCUSSION
Food Acceptance
The food acceptance of early fourth instar larvae and adult of
E. vigintioctopunctata is shown on Table 1. From the result it was found that
percent feeding of total treatment was higher in case of tomato (L. esculentum)
and second most position was found on aubergine (S. melongena) both of them
are solanaceae, E. vigintioctopunctata is a stern pest of solanaceous crops all over
the world (Maurice and Kumar 2012). According to Singh and Mukherjee (1987),
the larvae of E. vigintioctopunctata developed only on solanaceous hosts. Sugar
compounds have been known as feeding stimulants for many insects (Bernays and
Simpson 1982). The adults may also feed on members of other plant families,
possibly including cucurbits but these are secondary or occasional hosts. The
beetle would feed on cucumber (C. sativus) to a limited extent in the laboratory if
no other food was provided. It is also possible that some cultivated varieties of
cucurbits have lost their normal plant defences, thus allowing
E. vigintioctopunctata to feed on them (Chue 1930). Adult beetle attacked
cucurbitaceous plants when they cannot find solanaceous plant to feed.
Secondary compounds such as cucurbitacin contained specifically in
cucurbitaceous plants that act as feeding stimulants for E. vigintioctomaculata, on
the contrary, solanine and tomatine contained specifically in potato and tomato
did not stimulate the feeding of E. vigintioctomaculata (Abe and Matsuda 2000).
According to Richards and Filewood (1990), the food preference of
E. vigintioctopunctata is influenced by odour, taste, and age of host plant and also
by thickness of leaves, proportion of crude fibres, parenchymatous tissue and
water content.
Tabel 1 Percentage of feeding on tested host plants
Common name
Scientific name
Family
%
feeding
Tomato
Aubergine
Potato
Cucumber
Cutleaf ground cherry
Pumpkin
Bitter gourd
Red bean
Long bean
Broad bean
Pipinola
Bottle gourd
Lycopersicon esculentum
Solanum melongena
S. tuberosum
Cucumis sativus
Physalis angulata
Cucurbita pepo
Momordica charantia
Vigna angularis
V. sesquipedalis
Vicia faba
Sechium edule
Lagenaria leucantha
Solanaceae
Solanaceae
Solanaceae
Cucurbitaceae
Solanaceae
Cucurbitaceae
Cucurbitaceae
Leguminosae
Leguminosae
Leguminosae
Cucurbitaceae
Cucurbitaceae
99
97
95
40
35
30
0
0
0
0
0
0
14
E. vigintioctopunctata does not accept M. charantia, V. angularis,
V. sesquipedalis, V. faba, S. edule, and L. leucantha. Acceptance or rejection of
any host plant by an insect may be ascribed to the presence of attractants which
stimulate feeding and support growth or repellents inhibit feeding (Thorsteinson
1960). Plant odours can attract or repel insects, in either case the volatile plant
constituent affects the orientation of the insect with respect to the plant (Dethier et
al. 1960). The acceptability of plants to herbivorous insects is influenced by the
secondary chemicals. Unpalatability of secondary chemicals is not necessarily
associated with detrimental effects, but their presence influence size and duration
of feeding (Chapman 1990). Undoubtedly, these compounds play an important
role in limiting defoliation and consequently reducing food consumption by insect
herbivores (Hinks et al. 1993).
Leaf Areal Damage
From this experiment, it was found that among the four solanaceous and two
cucurbitaceous leaves the larvae and adult beetle mostly prefer on S. melongena
leaf with the average value of feeding area per day were 6.75 cm 2/insect and
1.771cm2 /insect followed by L. esculentum 4.416 cm2/insect and 1.35 cm2/insect.
Larvae and adult beetle showed variation of feeding responses in case of
C. sativus and C. pepo. Larvae were fed less amounts of C. sativus and more
C. pepo with the average value of 0.01 cm2/insect/day and 2.61 cm2/insect/day but
on the opposite way that adults were fed more C. sativus and less amount of
C. pepo with average value 0.42 cm2/insect/day and 0.08 cm2/insect/day,
respectively (Figure 5).
.
Figure 5 Feeding consumption by larvae and adult of E. vigintioctopunctata on
several host plants
15
Graphical representation of feeding by larvae and adult of
E. vigintioctopunctata also shows that higher damage occurs by larvae rather than
adult on four types of food among the six tested foods. Larvae are voracious and
mobile particularly in the last instar (Khan et al. 2000, Kalshoven 1981).
According to Dhamdhere et al. (1990), tomato and aubergine are the most suitable
food for E. vigintioctopunctata. Abe and Matsuda (2000, considered that
E. vigintioctopunctata are possibly stimulated to feed by some other substances
contained in solanaceous host plants. Methyl linolenate that are present in
solanaceous plants and rich in potato leaves plays an important role in the host
selection of E. vigintioctomaculata (Endo et al. 2004). Schoonhoven et al. (2005),
mentioned that the nutritional value affect on feeding behavior of insect. Photoperiod, temperature, and cues related to the physiological condition of the plant
involved in the behavioral switch with respect to host-plant selection. Seasonal
factors may have changed the chemistry and/or nutritional value of potential host
plants to such an extent that the insect switches from one plant species to another.
Also, the insect’s innate preferences may have changed. Feeding behaviour may
change drastically with the transition from larva to adult, owing to altered
nutritional requirements and environmental conditions.
Food Effeciency
The result showed that both averages consumption rate (CR) and relative
rate of consumption (RCR) of the early fourth instar larvae were 1.5x105 µg/day
and 2.44 µg/µg larvae/day in L. esculentum higher than 1.0x105µg/day and 1.78
µg/µg larvae/day in S.melongena leaves, respectively (P=0.002; t= -3.38, P=0.02;
t= -2.25). On the contrary, the growth rate was 3723.75 µg/day in S. melongena
higher than 2984.81 µg/day in L. esculentum (P = 0.01; t= 2.39). Both averages
relative growth rate (RGR) and efficiency of conversion of digested food (ECD)
also higher in S. melongena leaf with the value 0.64 µg/ µg /day and 43.17%
compared with L. esculentum leaf 0.48 µg/ µg /day and 19.94% (P= 0.004;
t= 3.03, P= 0.005; t= 3.16).
It seem different feeding activity happened in the late intars larvae. The
consumption rate (CR) was 7450.23 µg/day relatively higher in S. melongena
compared with 5506.07 µg/day in L. esculentum (P= 0.21; t= 0.82). The average
growth rate (GR) showed negative values in both S. melongena and L. esculentum
leaves were -529.45 µg/day, -649.62 µg/day, respectively (P= 0.39; t= 0.28)
(Tabel 2 and 3).
Food consumption and utilization are influenced by various biotic and
abiotic factors (Reynolds and Nottingham 1985), of which the most important are
atmospheric temperature and humidity at the time of rearing (Benchamin and
Jolly 1984). Growth also depends on the digestion and utilization of food, which
varies from species to species and even between different sexes of the same
species (Rahmathulla and Suresh 2011). Ashfaq et al. 2000 stated that thickness
and leaf water contents of the leaf played a significant role in the negative or
positive responses on food consumption and utilization. According to Chapman
(1998), food quality influenced the efficiency of utilization of food. Relative
consumption rate is inherently dependent on physiological response; the
maximum amount of food was not effectively used for the development of the
body (Farrar et al. 1989).
16
E. vigintioctopunctata is a holometabolous insect which life cycle is in egg,
larvae, pupae and adult. Late fourth instar larvae E. vigintioctopunctata is the
instar just before pupae, so insect little bit or no feed on this stage and is preparing
to become a pupae. According to David (2010), pupae are the resting and non
feeding stage of wing insects, included beetle. Young or old leaf may not be
influenced feeding behavior in case of late fourth instar larvae because same leaf
has been used in case of early and late fourth instar larvae and early fourth instar
larvae shows more feeding response.
Insects, like all living organisms, require energy and nutrients for survival,
growth and reproductive activity. The nutritional components (e.g. protein,
carbohydrates, fats, vitamins, minerals) of ingested food may or may not be
digested and absorbed. The proportion of digested food that is actually
transformed into net insect biomass is denoted by ECD, the efficiency of
conversion of digested food (Lindroth 1993). In short, ECD indicate how efficient
the herbivore converts the food into a biomass. Food conversion efficiencies may
vary considerably within species. Many insects increase food consumption rates
in response to low concentrations of critical nutrient
EPILACHNA VIGINTIOCTOPUNCTATA ON SEVERAL HOST
PLANTS
HACHIB MOHAMMAD TUSAR
GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2013
DECLARATION
With due respect I hereby declare that this thesis “Host Acceptance and Food
Efficiency by Epilachna vigintioctopunctata on Several Host plants” is my own
work under the supervision of an advisory committee. It has not yet been
presented in any form in any educational institution. The sources of information
which is published or not yet published by other researchers have been mentioned
and listed in the reference of this thesis.
Bogor, January 2013
Hachib Mohammad Tusar
Reg. No. A351108061
ABSTRAK
HACHIB MOHAMMAD TUSAR. Penerimaan Inang dan Efisiensi Pakan oleh
Epilachna vigintioctopunctata pada Beberapa Tanaman Inang. Dibimbing oleh
ENDANG SRI RATNA dan TEGUH SANTOSO.
Epilachna vigintioctopunctata (Fabricius) (Coleoptera: Coccinellidae)
umumnya dikenal sebagai kumbang Hadda. Serangga ini bersifat fitofag dan dapat
menjadi hama utama serta menimbulkan kerusakan yang sangat berarti pada
tanaman Solanaceae. Kesesuaian hama dan tanaman inang tertentu dapat
mempengaruhi aktivitas makan dan kecernaan makanan yang mendukung
pertumbuhan dan perkembangan serangga. Hingga saat ini belum ada laporan
mengenai penerimaan dan kesesuaian pakan pada beberapa jenis tanaman inang
oleh E. vigintioctopunctata di Indonesia. Tujuan penelitian ini adalah menentukan
penerimaan inang dan mengukur efisiensi pakan oleh E. vigintioctopunctata pada
beberapa jenis tanaman. Larva dan imago E. vigintioctopunctata mengerigiti dan
menelan daun pakan Solanum melongena, S. tuberosum, Lycopersicon
esculentum, Physalis angulata, Cucumis sativus, dan Cucurbita pepo sebagai
tanaman inang. Larva dan imago paling banyak memakan daun S. melongena
seluas 6.75 dan 1.771 cm2/serangga/hari, diikuti oleh L. esculentum 4.42 dan 1.35
cm2/serangga/hari. Rata-rata daun L. esculentum yang dimakan oleh larva instar
empat awal sebesar 1.5 x 105 µg/serangga/hari lebih tinggi dari S. melongena
1.0 x 105 µg/serangga/hari. Sebaliknya, tingkat pertumbuhan rata-rata dan
efisiensi konversi pakan yang dicerna oleh larva berturut-turut sebesar
3723.7 µg/serangga/hari dan 43.17% pada daun S. melongena lebih tinggi
dibandingkan L. esculentum sebesar 2984.8 µg/serangga/hari dan 19.94%. Tingkat
konsumsi kumbang E. vigintioctopunctata pada S. melongena rendah namun
memiliki efisiensi cerna pakan yang tinggi.
Kata kunci: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, efisiensi konversi pakan, interaksi tanaman inang.
ABSTRACT
HACHIB MOHAMMAD TUSAR. Host Acceptance and Food Efficiency by
Epilachna vigintioctopunctata on Several Host Plants. Supervised by ENDANG
SRI RATNA and TEGUH SANTOSO.
Epilachna vigintioctopunctata (Fabricius) (Coleoptera: Coccinellidae) is
commonly known as hadda beetle. This insect is a phytophagous and causes a
serious pest and built a tremendous damage to solanaceaeous crops. The
suitability of a certain host plant could affect on feeding activity and digestibility
of food that support insect growth and development. Recently, food acceptance
and suitability on several varieties of host plants by E. vigintioctopunctata has not
been reported in Indonesia. The objective of this research was to investigate the
host acceptance and food efficiency by E. vigintioctopunctata on several host
plants. Both larvae and adults bite on six species of leaves Solanum melongena,
S. tuberosum, Lycopersicon esculentum, Physalis angulata, Cucumis sativus, and
Cucurbita pepo. The larvae and adult beetles mostly fed on S. melongena with the
areal leaf consumed 6.75 and 1.771 cm2/insect/day, followed by L. esculentum,
4.416 and 1.35 cm2/insect/day. The average rate of consumption on L. esculentum
by early 4th instar larvae was 1.5 x 105 µg/insect/day higher than S. melongena
was 1.0 x 105 µg/insect/day. On the other hand, the average growth rate and
efficiency of conversion of digested food were 3723.7 µg/insect/day and 43.17%
higher than in S. melongena than L. esculentum were 2984.8 µg/insect/day and
19.94% respectively. This beetle has low consumption but high efficiency of
utilization food on S. melongena.
Key words: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, food conversion efficiency, host plant interaction.
SUMMARY
HACHIB MOHAMMAD TUSAR. Host Acceptance and Food Efficiency by
Epilachna vigintioctopunctata on Several Host Plants. Supervised by ENDANG
SRI RATNA and TEGUH SANTOSO.
Epilachna beetle (Epilachna vigintioctopunctata Fabr.) (Family
Coccinellidae. Order: Coleoptera) is very important pest in Asia that commonly
attacks solanaceous plants. Both larvae and adults feed by scrapping the epidermal
tissues and built a characteristic skeletonized pattern on remaining leaves. The
affected leaves will dry and drop lead to reduce the bearing of the plants. In a high
population, this insect may damage up to 80%, even complete defoliation can
occur, resulting in total crop failure 10-20% yield loss in aubergine. The
suitability of a certain host plant might affect on feeding activity and digestibility
of food that support growth and development. The research is conducted to
investigate the host acceptance and food efficiency by Epilachna
vigintioctopunctata on several host plants.
This study showed that six species of Solanum melongena, Lycopersicon
esculentum, Solanum tuberosum, Physalis angulata, Cucumis sativus, Cucurbita
pepo were accepted as a fed for E. vigintioctopunctata out from 12 treated leaves
of Solanaceous, Cucurbitaeus and Legumineous plants. Between those six types
of food, the highest feeding area caused by larvae and adult was found on
S. melongena leaf 6.75 and 1.771 cm2/insect/day, respectively. The average rate of
consumption leaf L. esculentum by early 4th instar larvae was 1.5 x 105
µg/insect/day higher than S. melongena is 1.0 x 105 µg/insect/day respectively. On
the other hand, all food efficiency parameters above on late 4th instar larvae were
not significantly different found in both S. melongena and L. esculentum.
The outcome of this research will supply a basic knowledge of feeding
behavior, damaging host plant and a potency of growth and development of
insect. The result could support a complementary approach in integrated pest
management (IPM) program to reduce the extent of losses caused by
E.vigintioctopunctata.
Key words: Epilachna vigintioctopunctata, Solanum melongena, Lycopersicon
esculentum, food conversion efficiency, host plant interaction.
Copyright© 2013 Bogor Agricultural University
Copyright are protected by law
It is prohibited to cite all or part of this thesis without referring to and mentioning
the source. Citation only permitted for the sake of education, research, scientific
writing, report writing, critical writing or reviewing scientific problem; Citation
doesn’t inflict the name and honor of Bogor Agricultural University.
It is prohibited to republish and reproduce all or part of this thesis without the
permission of Bogor Agricultural University.
HOST ACCEPTANCE AND FOOD EFFICIENCY BY
EPILACHNA VIGINTIOCTOPUNCTATA ON SEVERAL HOST
PLANTS
HACHIB MOHAMMAD TUSAR
Thesis
as a part of the requirements for acheiving the degree of
Master of Science in Entomology at
the Department of Plant Protection
GRADUATE SCHOOL
BOGOR AGRICULTURAL UNIVERSITY
BOGOR
2013
Thesis External Examiner: Prof Dr Dadang, MSc.
Title of Thesis
:
Name
Registration number
:
:
Host Acceptance and Food Efficiency by Epilachna
vigintioctopunctata on Several Host Plants
Hachib Mohammad Tusar
A351108061
Approved by
Advisory Committee
Endang Sri Ratna, Ph.D.
Chairperson
Teguh Santoso, Ph.D.
Member
Agreed by
Head of the Program Study Entomolgy
Dean of Graduate School
Dr. Pudjianto, M.Si.
Dr. Dahrul Syah, M.Sc.Agr.
Date of Examination: 23 January 2013
Date of Completion:
ACKNOWLEDGEMENT
My first and foremost earnest gratitude to ALLAH SWT for blessing me
and gave me the ability to complete this study. Several people in one or another
way were contributed for the success of this work. I would like to convey my
sincere and special thanks to my main supervisor Dr. Endang Sri Ratna for her
guidance, encouragement, advice and constructive criticisms during the
preparation, laboratory analysis and finalizing this thesis. I also thankful to her for
allowing me to use her materials for conducting my research; otherwise this work
would not be completed in time.
I am also thankful to my second supervisor Dr. Teguh Santoso for his
valuable time and comments on this work. I am very much grateful to the
Ministry of National Education, Republic of Indonesian for giving me the
opportunity to do a Master of Science in Entomology from this prestigious Bogor
Agricultural University under the Developing Countries Partnership Scholarship
Program (DCPS).
I acknowledge to Dr. Pudjianto, M.Si. coordinator of major Entomology and
Djoko Prijono M.Agr.Sc. Lecturer, Research Methodology, IPB for their guidance
and encouragement throughout my study period. Special thanks also go to the
following people:
1.
The technicians and staff in the laboratory of Insect Physiology and
Toxicology at the Department of Plant Protection, who were always help
me. I am very much thankful to my Indonesian friends Herma Amalia
(Lecturer, IPB), Adeel ABD Alkarim Fadhl (Lecturer, Sana University,
Yemen), Maroning Useng (Lecturer, Yala Islamic University, Thailand) and
my Bangladeshi friends living in Indonesia: Md. Kamruzzaman (University
Padjadjaran, Bandung), Md. Shohel Rana (Gadjah Mada University,
Yogjakarta).
2.
My Bangladeshi teachers Prof. Md. Hamidur Rahman (Dept of Entomology,
PSTU), Prof. Dr. Md. Mohsin Hossain Khan (Dept of Entomology, PSTU),
Prof. Dr. Habibur Rahman (Dept of Entomology, PSTU), Dr. Mohammad
Atikur Rahman (Associate Prof. Dept of Entomology, PSTU),
Dr. Md. Hemayet Jahan (Associate Prof. Dept of Entomology, PSTU),
my friends A.B.M Mahbub Morshed Khan (Asst. Prof. Dept of Agricultural
Botany, PSTU), Liton Sen (Lecturer, PSTU), Arifur Rahman Noman (AFS,
PSTU), Rahat Mahmood (AFS, PSTU) and Zead Hassan (Upazilla
Secondary Education Officer) for their contribution on counseling and
moral support during the entire academic period.
Special thanks to my parents, my wife, my brothers, sister and my relatives
for their continued prayer.
Bogor, January 2013
Hachib Mohammad Tusar
CURRICULUM VITAE
The writer was born on 17th October 1982. His father Md. Quaum
Howlader and mother Aktarunnessa in Village: Jangalia, Post: Aorabunia, Thana:
Kathalia, District: Jhalakati. The writer is the first son in the family of four
children and was married on 20 August 2010 having one child. In 1997 the writer
achieved Secondary School certificate degree from Aorabunia Model High School
in Bangladesh. In 1999 he achieved Higher Secondary School Certificate from
Amrita lal Dey College and in 2000 he was admitted in Patuakhali Science and
Technology University under the faculty of Agriculture and was graduated with
bachelor of science in Agriculture degree in 2006. In 2007 the writer was getting
job at Patuakhali Science and Technology University, Bangladesh. In 2009, the
writer was get the opportunity to do a three years (With one year Bahasa
Indonesia Language course) Master of Science degree in Entomology at the
department of Plant Protection in Bogor Agricultural University, Bogor, Indonesia
under developing countries partnership scholarship program offered by the
Ministry of National Education, Government of Peoples of Republic of Indonesia.
CONTENTS
LIST OF TABLES
xii
LIST OF FIGURES
xii
INTRODUCTION
Background
Objectives of this Research
1
1
2
LITERATURE REVIEW
Biology of Epilachna vigintioctopunctata
Host Plant Interaction
Importance of Solanum melongena
Importance of Lycopersicon esculentum
Food Conversion Efficiency
3
4
5
6
7
MATERIALS AND METHODS
Time and Place of Research
Materials
Preparation of Plants
Preparation of Insects
Food Acceptance Test
Feeding Area Measurement
Food Efficiency Test
Data Analysis
8
8
8
8
9
10
10
11
RESULT AND DISCUSSION
Food Acceptance
Leaf Areal Damage
Food Efficiency
13
14
15
CONCLUSION AND RECOMMENDATION
17
REFERENCES
18
LIST OF TABLES
1 Percentage of feeding on tested host plants
2 The effects of two types of food on the rate of consumption, growth
rate and efficiency of utilization of food by early fourth instar larvae
E. vigintioctopunctata
3 The effects of two types of food on the rate of consumption, growth
rate and efficiency of utilization of food by late fourth instar larvae
E. vigintioctopunctata
13
16
16
LIST OF FIGURES
Rearing of E. viginctioctopunctata in the Laboratory
Acceptance test of E. viginctioctopunctata on twelve types of food
Measurement of feeding area of leaves
Efficiency test by using larvae E. viginctioctopunctata on S. melongena
and L. esculentum leaves
5 Feeding consumption by larvae and adult of E. vigintioctopunctata on
several host plant
1
2
3
4
9
9
10
12
14
INTRODUCTION
Background
Epilachna vigintioctopuncata (Fabricius) called hadda beetle is a somber
pest of important Solanaceaous crops such as aubergine, potatoes, tomatoes and
bitter gourds (Alam 1969; Richards and Filewood 1988). This pest can also attack
cucurbitaceous and leguminaceous crops (Imura and Ninomiya 1978). The
population of this beetle is distributed over an extensive geographical area such as
India, Pakistan, China, Japan, South East Asia, and Oceania (Katakura et al.
1988). This hadda beetle has four generation per year. In general, the peak
population is found from July to August (Kalshoven 1981). In Indonesia, the
larval population increased rapidly in November and caused seriously damage at
the end of December. Both larvae and adults feed on the leaves by scrapping the
epidermal tissue to form skeletonized pattern “windows like” that is a typical
hadda beetle scrapping (Imura and Ninomiya 1978). Further devastation shows
drying and dropping of the leaves leads to harshly distressed growth and yield of
the plant (Alam 1969). In a very high population, it evoked complete defoliation
resulting in a total crop failure (Rajagopal and Triveldi 1989). The damaging
plants could reach up to 80%. Alam (1969) reported that this beetle cause 10-20%
yield loss of aubergine.
Nutrients are substances that are necessary for growth, maintaining tissue,
reproduction, and supply energy for the organism. Most of the nutrients derived
from consumed food. Nutrients required by insects should be in balanced
proportion, if insects do not get nutritional balance so the insects growth, molting
and egg laying will be failured (Chapman, 1998). Nation (2001) mention that
nutrients such as carbohydrates, proteins, fats, sterols, vitamins, nucleic acids,
water and minerals are required by insects. Food becomes the cornerstone of
efforts to meet the nutrients that will support the growth and development of the
insects. The higher efficiency of utilization of food shows the higher quality of the
nutrients present in food (Schoonhoven et al. 1998).
According to Kogan (1982), in terms of the suitability of the host plant, the
nutritional value of food shows whether or not the food support physiological
processes related to growth and development of the larvae. Insect behavior in
accepting or rejecting food type can be affected by the chemicals contained in the
plant. Primary chemicals are parts of plants that used for growth or development
of insects, while secondary chemical has function for rejection (repellent),
inhibition of eating (antifeedant), attractants, or a deterrent.
The food that has been digested is to be used for growth and development,
while undigested food will be passed through the intestinal lumen in the form of
feces. Insect will choose the favorable food for maintaining survival of the fittest.
The quality and quantity of food plays a vital role on growth, development and
reproduction of insect (Maurice and Kumar 2012, Scriber and Slansky 1981).
Host acceptance and food efficiency by E. vigintioctopunctata has not yet been
done in Indonesia and for this reason this topic was selected for research.
According to Waldbauer (1968) there are three parameters for the efficiency of
utilization of food that is approximate digestibility (AD), efficiency of conversion
of digested food (ECD), and the efficiency of conversion of ingested food (ECI).
2
This research supplied an effective complementary approach in integrated
pest management (IPM) to reduce the extent of losses caused by
E. vigintioctopunctata. IPM looks for the weak links in the pest’s biology and
behavior (life cycle, food and habitat preferences and sources, how it feeds, mates,
reproduces, and disperses). These weaknesses are then exploited to manage the
pest by altering or removing one or more of the basic necessities.
Objectives
The objective of this research was to study host acceptance and food
efficiency by E. vigintioctopunctataon on several host plants.
3
LITERATURE REVIEW
Biology of Epilachna vigintioctopunctata
Epilachna vigintioctopunctata (Fabricius) has another synonym that is
Henosepilachna vigintioctopunctata (Evans 2012). The taxonomy of this species
remains confusing throughout history because of its wide variation in external
appearance. In Pakistan, this species has been called E. sparsa (Naz et al. 2012).
Hadda beetle E. vigintioctopunctata is polyphagous and a serious pest of
Solanaceous crops such as aubergine, potato, tomato over a wide range from
Japan to South Asia and Australia. In Bangladesh, a group of Solanaceae,
Cucurbitaceae and Leguminoceae crops were attacked by this insect (Alam 1969).
Moreover, it is as recorded pest of cucurbitaceous crops in India. In Pakistan,
E. vigintioctopunctata can be found with varying degree of population densities in
all the areas where the host plants are grown (Naz et al. 2012).
Adults are typically ladybird shaped. They are 5-8 mm long, convex
dorsally, flattened ventrally and the head is partly hidden beneath the pronotum.
Legs and antennae are relatively short. The upper surface is covered with fine,
short hairs. Tarsi are composed of four segments. The second segment from the
base is strongly lobed underneath, while the third segment is very short and small,
and is the same width as the base of the claw-bearing fourth segment (Fabricius
2000). E. vigintioctopunctata has a typical angled of elytral apex. First coxal line
is subcomplete. Elytral spots vary between 12 and 28. There are two species one
having 12 spots, Epilachna 12-stigma and another having as many as 28 spots,
Epilachna 28-punctata (Anonym 2012). Exact diagnosis can be made by
examining male genitalia with a well developed basal knife edge and apical thorn
on median lobe, siphonal tip tapering on one side. The female genitalia have a
deep notch on inner edge. The male genitalia, the median lobe has a basal knife
edge beginning at the foot of paramera and a buldge beyond the middle, after
which it curves up into an apical hook. Paramera with an apical thorn and covered
with hairs shorter than those of median lobe. Siphon gently curved near the base,
then straight, ending in a point. The female genital plates has an excavation on the
underside with a sharp dark edge toward apex. In the male, the hind margin of the
sixth visible sternite is concave; in the female. It has a deep median split. The
tarsal claws each have three distinct teeth, the basal tooth is subrectangular
(Fabricius 2000).The pronotum presents variable maculation (Naz et al. 2012).
The ovoid elytra are broadest in the anterior quarter, and strongly convex,
without broadly explanate lateral margins. The sutural angle has a very weak
tooth and is not entirely evenly rounded. The ground colour is brownish-yellow to
dark brown, with 6-14 black spots on each elytron and seven on the pronotum.
Newly emerged adults are entirely yellow, but as the body hardens, dark spots
develop over 6-12 hours. Antennae are moderate in length; longer than the width
of the frons, but shorter than the head width; the last three segments forming an
asymmetrical club. The anterior angles of the pronotum are produced anteriorly,
and are strongly rounded externally. The punctation of the head and pronotum is
close, with shining intervals. The punctation of the elytra is double, with very
fine, close-set punctures. The postcoxal plates on the first visible sternite of the
4
abdomen are rounded, do not reach the hind margin of the segment, and are
incomplete externally (Fabricius 2000).
Eggs are yellow, elongate, oval and usually laid on the under surface of a
leaf in small batches of 5-40. The eggs are attached on the upper side of the leaf
surface by a short stalk at its base. The egg is slightly broader basally than
apically gave its length as 1.1 mm and its width as 0.4 mm. Larva have the
appearance of the typical ladybird larva. The larval body has elongate and
elliptical shaped with moderately long legs and a well-developed head and
mandibles. The body is covered with long branched processes bearing spines.
There are four larval instars. The final-instar larva is about 6 mm long and 2.8 mm
wide across the third abdominal segment. It is generally has pale yellow colour,
although the more sclerotized parts and areas around the base of the scoli are
brown.
The pupa of E. vigintioctopunctata is white initially, turning yellow later,
with brown spots appearing on the dorsal surface. Its size was 4.6 mm long and
3.7 mm wide. The pupal period lasts about 4 days (Fabricius 2000).
E. vigintioctopunctata is found active from April to middle of October and
highest population was recorded (8.14 beetles/plant) during middle of September
in Terai region, India. Population of this beetle showed significant positive
correlation with average temperature, relative humidity and weekly rainfall.
Duration of life cycle shortest (26.71 days) in June-July and longest (33.52 days)
in September-October. Highest fecundity (272.32 eggs) is recorded during MarchApril. Life cycle and fecundity is negatively and positively correlated with
temperature and relative humidity respectively. High temperature and humidity
during July to September decreased the duration of life cycle and increased
fecundity leading into rapid multiplication of pest resulting higher population
level and there by crop loss during the period (Ghosh et al. 2001).
Hadda beetle feeds actively in the morning and evening hours and feeding
declines rapidly in the middle of the day and after midnight. The daily fluctuation
in the rate of feeding depends mainly on the temperature which determined the
level of metabolism (Tilavov 1981).
Host-Plant interaction
Three optical characteristics of plants may influence host selection behavior
that is spectral quality, dimensions (size), and pattern (shape). In the process of
host-plant selection, two main consecutive phases are searching and contacttesting. The first phase may end with the event of finding; the second phase ends
with acceptance or rejection. Acceptance is a crucial behavioral decision as it
results in ingestion of plant materials. Standardized host-plant selection sequences
are (1) the insect has no physical contact with a plant and either rests or moves
about randomly, walking or flying. (2) It perceives plant-derived cues, optical
and/or olfactory. (3) It responds to these cues in such a way that the distance
between its body and the plant decreases. (4) The plant is found, i.e. it is contacted
by either touching or climbing it, or by landing on it. (5) The plant surface is
examined by contact-testing. (6) The plant may be damaged and the content of
tissues released by nibbling or test-biting (in the case of biting-chewing species),
probing (piercing-sucking species), or puncturing with the ovipositor. (7) The
plant is accepted or is rejected, resulting in the insect’s departure. During each of
5
these steps the insect may decide to turn away from the plant before contacting it,
or to leave it after contact (Schoonhoven et al. 2005).
Upon contact with the plant an insect obtains additional information on
plant quality through tactile (mechanosensory) and contact chemosensory (taste or
gustatory) stimuli. Physical features of plant organs or tissues can profoundly
influence host-plant selection behaviour. Acceptance of the plant depends upon
the nature of the sensory input elicited from appropriate receptors at each relevant
stage in this host finding process. The complex patterns created by positive and
negative sensory inputs that produce behavioral responses are the result of neural
integration which probably occurs within decision-making centers in the higher
central nervous system (CNS). Each plant contacted will induce a certain level of
excitation, and in that way can be assigned a rank order of preference to an insect,
but the level of excitation will be dependent upon factors influencing the plant
such as seasonal effects, plant quality and induced plant defenses (Withers 1997).
Host finding behavior will change with an insect physiological condition (such as
nutritional state, oocyte dynamics, age and stage of development (Barton 1993).
The presence of trichomes and wax crystal structures on the plant surface, leaf
thickness and toughness, sclerotization, and high silica content may cause
avoidance behavior, and such plant traits are assumed to often fulfill a defensive
function (Schoonhoven et al. 2005).
Importance of Solanum melongena
Aubergine (Solanum melongena), is an easily cultivated plant belonging to
the family Solanaceae. Its fruit is high in nutrition and commonly consumed as a
vegetable. The fruit and other parts of the plant are used in traditional medicine.
Aubergine fruits can also be pureed, flavoured, and used as a dip or chutney that
is popular in Mediterranean and Indian cuisine. In indian cuisine, they are used in
curries and even made into soufflés. In traditional chinese medicine, all parts of
the plant can be used to stop intestinal bleeding. The fruit of the plant is used as an
antidote in cases of mushroom poisoning. In indochina, parts of the plant are used
as a purgative. For traditional malay medicine, the ashes of the fruit are used in
dry, hot poultices to treat haemorrhoids. To treat ulcers, the root is pounded and
applied inside the nostrils (Thulaja 2012). In particular the fruit helps to lower
blood cholesterol levels and is suitable as part of a diet to help regulate high blood
pressure. It is also used as an antidote to poisonous mushrooms. It is bruised with
vinegar and used as a poultice for cracked nipples, abscesses and haemorrhoids.
The leaves are narcotic. A soothing and emollient poultice for the treatment of
burns, abscesses, cold sores and similar conditions can be made from the leaves.
Aubergine leaves are toxic and should only be used externally. The ashes of the
peduncle are used in the treatment of intestinal haemorrhages, piles and toothache
(Anonym 2012).
The fruit should not be eaten raw. It can be baked, stewed or added to soups,
curries etc. The fruit is said to be very nutritious. It is a good source of vitamin C
and potassium. The fruit can be up to 20 cm long in cultivated plants (Anonym
2012). The aubergine is used mainly as a food crop. Solanum melongena is a
perennial growing to 1 m. The flowering season occured from July to September,
and the seeds ripen from August to October. The flowers are hermaphrodite and
are pollinated by Insects. (Anonym 2012).
6
Aubergine is one of the most common and popular vegetable crops
cultivated in Bangladesh. It is grown year-round having two major growing
seasons such as summer and winter. Aubergine is one of the rare vegetables,
which can be grown also in summer. It covers an area of 74,711 acres, which is
about 15% of total vegetable areas of the country. Although the crop is grown
throughout the country, it is intensively and commercially grown in Jessore,
Narsinghdi, Dhaka, Comilla and Bogra districts. Its annual production is about
191,525 metric tons with an average yield of 2.56 metric tons per acre. One of the
major factors of low yield of aubergine is insect pest such as aubergine shoot and
fruit borers, leafhoppers and Hadda beetles that causes serious damage to the crop
(Rahman 2009).
Aubergine is a relatively easy to cultivate and high-yielding vegetable with
a reasonable nutritional value. It should be possible to breed into aubergine
resistance for the more destructive pest and diseases which occur in the tropics.
This vegetable is in increasing demand in more affluent countries and are good
prospects for export from the tropics and subtropics (CAB 2007).
Importance of Lycopersicon esculentum
Information about the exact date for the first time growing tomatoes is not
specified, the tomato was grown in about 500 years before Christ. This plant is
native to South America and Central America. During the Spanish colonial period
tomato was transferred to other parts of the world i.e. Peru in the sixteenth century
and seventeenth-century England and reached to the Netherland. In the early
nineteenth century, tomatoes were distributed in the Middle East. Tomato is used
as one of the cooking materials. Now a days thousands of (near 7500) tomato
varieties are grown throughout the world. Consumption of tomato as a vegetable
began since the nineteenth century. According to global statistics 2008, about 130
million tons of tomatoes were produced in the world. China, America, Turkey,
India, Italy, Egypt and Iran were the largest producer of tomatoes (Mohammad
2011).
Lycopersicon esculentum is an annual growing crops. It is in flower from
Jun to September, and the seeds ripen from August to October. The flowers are
hermaphrodite and are pollinated by insects, self. L. esculentum can be used as a
savoury vegetable or flavouring in cooked foods, or can be eaten out of hand as a
dessert fruit. It is much used in salads and as a flavouring in soups and other
cooked foods. A juice made from the fruit is often sold in health food shops. The
fruit can also be dried and ground into a powder that can be used as a flavouring
and thickening agent in soups, breads, pancakes etc. An edible oil is obtained
from the seed. It is suitable for culinary purposes (Anonym 2012).
The pulped fruit is an extremely beneficial skin-wash for people with oily
skin. Sliced fruits are a quick and easy first aid treatment for burns, scalds and
sunburn. A decoction of the root is ingested in the treatment of toothache. The
skin of tomato fruits is a good source of lycopine, a substance that has been shown
to protect people from heart attacks. It seems to be more effective when it is
cooked and food products such as tomato ketchup and tinned tomatoes can be
obtained from tomato. Lycopine has also been shown to have a very beneficial
effects upon the prostate and is being used increasingly to treat enlarge prostate
7
and the difficulties in urination. A homeopathic remedy is made from the plant. It
is used in the treatment of rheumatism and severe headaches (Anonym 2012).
Food conversion efficiency
Food conversion efficiencies may vary considerably within a species. One
cause of such variation involves homeostatic (The ability or tendency of an
organism or cell to maintain internal equilibrium by adjusting its physiological
processes) adjustment of consumption rates and efficiency parameters such that an
insect can approach its ideal growth rate even with foods of different quality in
various environments. For example, insects that experience reduced ECDs due to
increased respiratory costs may be able to compensate by increasing consumption
rates or digestion efficiencies (ADs). Not all changes are homeostatic, however.
For instance, many insects increase food consumption rates in response to low
concentrations of critical nutrients such as protein. Other nonhomeostatic changes
in efficiency values may occur in response to plant allelochemicals. For example,
compensatory feeding to increase intake of a limiting nutrient may simultaneously
increase exposure to plant toxins, which in turn may reduce ECDs.
Intraspecific variation in food conversion efficiencies may also be related to insect
development (Lindroth 1993).
Food conversion efficiencies also vary greatly among species and this
variation is more closely related to feeding guilds than to taxonomic affinity. The
insects that feed on nitrogen-rich foliage generally have higher consumption rates
and assimilation efficiencies than do insects that feed on nitrogen-poor foliage,
and as a consequence grow and develop much faster. The relatively poor
nutritional quality of tree foliage has had important consequences for insect life
histories. In temperate regions forb feeders often have many more generations per
year than do tree feeders. Among tree-feeders, numerous species have adapted to
emerge and feed only on the especially nutritious early spring foliage, and thus
have only one generation per year. Growth rates are low due to low consumption
rates and low ECDs. Low ECDs may result from a requirement of these insects to
metabolize digested food in order to produce water (Lindroth 1993).
8
MATERIALS AND METHODS
Time and Place of Research
All experiments were conducted in the laboratory of Insect Physiology and
Toxicology, Bogor Agricultural University from June 2012 to November 2012.
Materials
The materials that were used for this experiment were leaves of Solanum
melongena, Solanum tuberosum, Lycopersicon esculentum, Physalis angulata,
Cucumis sativus, Cucurbita pepo, Momordica charantia, Vigna angularis,Vigna
sesquipedalis, Vicia faba, Sechium edule, Lagenaria leucantha, Plastic cylinder,
Larvae and adults of E. vigintioctopunctata, Electronic balance (GR 150, AND
Company limited, Japan), Leaf area meter (CI-202, product of CID, INC. USA),
etc.
Methods
Preparation of Plants
Twelve host plants S. melongena, S. tuberosum, L. esculentum, P. angulata,
C. sativus, C. pepo, M. charantia, V. angularis, V. sesquipedalis, V. faba, S. edule,
and L. leucantha were used in this study. The leaves conducted for acceptance and
feeding area measurement test were picked up from the farmer organic field
surrounding Bogor area, while the leaves conducted for efficiency test was
collected from growing plant in the laboratory.
Two plant species used for the efficiency test were aubergine (S.
melongena) and tomato (L. esculentum). Seeds were supplied from the market and
singly planted in a polythene (10 cm in diameter and 20 cm in depth) with soil
media. The plants were maintained with insecticide-free. The leaves used for the
experiment were about two months aged when they had approximately 5-10 true
leaves.
Preparation of Insects
Beetle was previously identified according to the reference from insect
standard collection that is available in the museum of Insect Biosystematic
Laboratory and books (Kalshoven 1981; CSIRO 1991). Two sources of beetle E.
viginctioctopunctata were carried out in this study. The beetles used for
acceptance test were collected from the agricultural fields neighboring Bogor
Agricultural University area and the beetles used for feeding area measurement
and food efficiency tests were provided from laboratory mass rearing insect.
The maintaining of the insect stock culture was conducted in the laboratory
of Insect Physiology and Toxicology, Bogor Agricultural University under
temperature between 26-28oC and 85-87% relative humidity.
Adult beetles were collected from the fields and were subsequently reared in
an aubergine plant. Mating pairs was parted and kept in plastic cylinder (7 cm in
diameter and 20 cm in height) contained aubergine leaves (Figure 1). The mated
females were allowed laying eggs and the hatched eggs were continuously
maintained until producing fourth instar larvae that were used for the experiment.
9
Figure 1 Rearing of E. viginctioctopunctata in the laboratory
Food Acceptance Test
Early fourth instars larvae and adult beetles were singly placed in a plastic
container which contains a sheet leaf with size 6 x 3 cm as a food treatment
(Figure 2). These beetles feeding behavior were observed in 5 days for twelve
types of plant and food were changed every 24 hrs and damage leaves caused by
feeding activity were collected. Each 10 replications were conducted to both
stages of beetles. The acceptable food was evaluated and the percent feeding on
total treatment was calculated. This experiment was conducted by using no choice
method described by Teparkum (2000).
Calculation has been down by using following formula:
Feeding on total replication (%) = total feeded replication x 100/ total replication
Figure 2 Acceptance test of E. viginctioctopunctata on twelve types of food
10
Feeding Area Measurement
Six species of plants S. melongena, S. tuberosum, L. esculentum,
P. angulata, C. sativus, and C. pepo resulted from a previous experiment were
used for feeding area measurement test. The method of introducing beetles to their
food was the same as described previously in food acceptance test. Each 10
replications were conducted to both stages of beetles. Observation has been done
for one day. Feeding areas was measured by using leaf area meter machine
(CI-202, CID, INC. USA) (Figure 3).
Figure 3 Measurement of feeding area of leaves
Efficiency Test
Two types of larvae were used for carried out this experiment that is early
fourth instars with the age of one day after molt and late fourth instars with the
age of three days after molt.
Determine of dry weight of leaves and larval proportion. Food
S. melongena and L. esculentum that was found as mostly fed from the previous
experiment was cut each of 10 pieces about the size of 6 x 3 cm. Then, the 10
pieces of leaves of each type was weighted initially (wet weight). After that 10
pieces of each type of leaf was wrapped separately into aluminum foil and then
put into the oven for 2 hours at 105 °C. After two hours, each envelope containing
single piece of leave was weighted (dry weight). If the weight after dry is marked
by y and initial weight or wet weight is marked by x, then proportion of dry
weight of leaves y/x which is necessary for calculating initial dry weight of leaves
to get food consumption rate (CR).
The initial weight of larvae was estimated using 20 larvae divided each by
10 feed on S. melongena and 10 on L. esculentum. Larvae were wrapped by
aluminum foil individually and put into the oven for 2 hours at 105 °C. After two
hours, dry weight larvae were measured. If the initial weight (wet) is given the
symbol (x) and dry weight symbol (y), then the proportion of dry weight of the
larvae is y/x which is necessary for calculating initial dry weight of larvae to get
growth rate (GR).
11
The utilization of food. To determine the utilization of food by the larvae,
the following work has been conducted.
A piece of leaf S. melongena and L. esculentum was cut into 6 x 3 cm in size
approximately then weighed separately. After that the cut leaf was placed into the
petri dish individually. One of fourth instar larva was weighted initially and then
placed into a petri dish and then closed. The larva was kept to feed for 24 hrs
(Figure 4). This treatment was repeated 10 times for each leaf and each stage of
larvae. All treatments were labeled in accordance with the treatment and
repetition.
After 24 hrs, the larvae were removed from petri dish. Each larva and the
remained leaf were wrapped separately by aluminum foil. Each has been labeled
based on treatment and repetition. Both samples of larvae and leaf were allowed
to dry within the oven for 2 hrs at 105 °C. All samples were removed from the
oven and kept in room temperature and then the sample was weighed individually.
In case of undetermined fecal larvae from this experiment, so the weight was
assumed zero. The measurements of efficiency parameter were calculated
according to the equation below:
1. CR = ΔC/PF
ΔC = IDWL – FDWL
CR
=
PF
=
IDWL =
FDWL =
2.
RCR
RCR = CR/AW
AW = IDWL + FDWL/2
Consumtion rate (µg/day)
Period of feeding
Initial dry weight of leaf
Final dry weight of leaf
= Relative consumption rate (µg
leaf / µg larvae/ day)
AW = Average weight of larvae
IDWL = Initial dry weight of larvae
FDWL = Final dry weight of larvae
3. GR = FDWL IDWL/PF
GR
= growth rate (µg/ day)
FDWL = Final dry weight of larvae
IDWL = Initial dry weight of larvae
4. RGR= GR/AW
RGR
= Relative growth rate (µg/µg
larvae/ day)
5. AD = ΔC- WF/ ΔC x100%
AD
WF
= Approximate digestibility (%)
= Weight of fecal larvae
6. ECI = GR/ CR x 100%
ECI
= Efficiency of conversion of
ingested food (%)
7. ECD = GR/ CR – WF x 100%
ECD
= Efficiency of conversion of
digested food (%)
Measurements has been done by using gravimetric method (Waldbauer 1968)
with t- test Microsoft excel at 5% level of significance.
12
Figure 4 Efficiency test by using larvae of E. viginctioctopunctata on
S. melongena and L. esculentum leaves
13
RESULT AND DISCUSSION
Food Acceptance
The food acceptance of early fourth instar larvae and adult of
E. vigintioctopunctata is shown on Table 1. From the result it was found that
percent feeding of total treatment was higher in case of tomato (L. esculentum)
and second most position was found on aubergine (S. melongena) both of them
are solanaceae, E. vigintioctopunctata is a stern pest of solanaceous crops all over
the world (Maurice and Kumar 2012). According to Singh and Mukherjee (1987),
the larvae of E. vigintioctopunctata developed only on solanaceous hosts. Sugar
compounds have been known as feeding stimulants for many insects (Bernays and
Simpson 1982). The adults may also feed on members of other plant families,
possibly including cucurbits but these are secondary or occasional hosts. The
beetle would feed on cucumber (C. sativus) to a limited extent in the laboratory if
no other food was provided. It is also possible that some cultivated varieties of
cucurbits have lost their normal plant defences, thus allowing
E. vigintioctopunctata to feed on them (Chue 1930). Adult beetle attacked
cucurbitaceous plants when they cannot find solanaceous plant to feed.
Secondary compounds such as cucurbitacin contained specifically in
cucurbitaceous plants that act as feeding stimulants for E. vigintioctomaculata, on
the contrary, solanine and tomatine contained specifically in potato and tomato
did not stimulate the feeding of E. vigintioctomaculata (Abe and Matsuda 2000).
According to Richards and Filewood (1990), the food preference of
E. vigintioctopunctata is influenced by odour, taste, and age of host plant and also
by thickness of leaves, proportion of crude fibres, parenchymatous tissue and
water content.
Tabel 1 Percentage of feeding on tested host plants
Common name
Scientific name
Family
%
feeding
Tomato
Aubergine
Potato
Cucumber
Cutleaf ground cherry
Pumpkin
Bitter gourd
Red bean
Long bean
Broad bean
Pipinola
Bottle gourd
Lycopersicon esculentum
Solanum melongena
S. tuberosum
Cucumis sativus
Physalis angulata
Cucurbita pepo
Momordica charantia
Vigna angularis
V. sesquipedalis
Vicia faba
Sechium edule
Lagenaria leucantha
Solanaceae
Solanaceae
Solanaceae
Cucurbitaceae
Solanaceae
Cucurbitaceae
Cucurbitaceae
Leguminosae
Leguminosae
Leguminosae
Cucurbitaceae
Cucurbitaceae
99
97
95
40
35
30
0
0
0
0
0
0
14
E. vigintioctopunctata does not accept M. charantia, V. angularis,
V. sesquipedalis, V. faba, S. edule, and L. leucantha. Acceptance or rejection of
any host plant by an insect may be ascribed to the presence of attractants which
stimulate feeding and support growth or repellents inhibit feeding (Thorsteinson
1960). Plant odours can attract or repel insects, in either case the volatile plant
constituent affects the orientation of the insect with respect to the plant (Dethier et
al. 1960). The acceptability of plants to herbivorous insects is influenced by the
secondary chemicals. Unpalatability of secondary chemicals is not necessarily
associated with detrimental effects, but their presence influence size and duration
of feeding (Chapman 1990). Undoubtedly, these compounds play an important
role in limiting defoliation and consequently reducing food consumption by insect
herbivores (Hinks et al. 1993).
Leaf Areal Damage
From this experiment, it was found that among the four solanaceous and two
cucurbitaceous leaves the larvae and adult beetle mostly prefer on S. melongena
leaf with the average value of feeding area per day were 6.75 cm 2/insect and
1.771cm2 /insect followed by L. esculentum 4.416 cm2/insect and 1.35 cm2/insect.
Larvae and adult beetle showed variation of feeding responses in case of
C. sativus and C. pepo. Larvae were fed less amounts of C. sativus and more
C. pepo with the average value of 0.01 cm2/insect/day and 2.61 cm2/insect/day but
on the opposite way that adults were fed more C. sativus and less amount of
C. pepo with average value 0.42 cm2/insect/day and 0.08 cm2/insect/day,
respectively (Figure 5).
.
Figure 5 Feeding consumption by larvae and adult of E. vigintioctopunctata on
several host plants
15
Graphical representation of feeding by larvae and adult of
E. vigintioctopunctata also shows that higher damage occurs by larvae rather than
adult on four types of food among the six tested foods. Larvae are voracious and
mobile particularly in the last instar (Khan et al. 2000, Kalshoven 1981).
According to Dhamdhere et al. (1990), tomato and aubergine are the most suitable
food for E. vigintioctopunctata. Abe and Matsuda (2000, considered that
E. vigintioctopunctata are possibly stimulated to feed by some other substances
contained in solanaceous host plants. Methyl linolenate that are present in
solanaceous plants and rich in potato leaves plays an important role in the host
selection of E. vigintioctomaculata (Endo et al. 2004). Schoonhoven et al. (2005),
mentioned that the nutritional value affect on feeding behavior of insect. Photoperiod, temperature, and cues related to the physiological condition of the plant
involved in the behavioral switch with respect to host-plant selection. Seasonal
factors may have changed the chemistry and/or nutritional value of potential host
plants to such an extent that the insect switches from one plant species to another.
Also, the insect’s innate preferences may have changed. Feeding behaviour may
change drastically with the transition from larva to adult, owing to altered
nutritional requirements and environmental conditions.
Food Effeciency
The result showed that both averages consumption rate (CR) and relative
rate of consumption (RCR) of the early fourth instar larvae were 1.5x105 µg/day
and 2.44 µg/µg larvae/day in L. esculentum higher than 1.0x105µg/day and 1.78
µg/µg larvae/day in S.melongena leaves, respectively (P=0.002; t= -3.38, P=0.02;
t= -2.25). On the contrary, the growth rate was 3723.75 µg/day in S. melongena
higher than 2984.81 µg/day in L. esculentum (P = 0.01; t= 2.39). Both averages
relative growth rate (RGR) and efficiency of conversion of digested food (ECD)
also higher in S. melongena leaf with the value 0.64 µg/ µg /day and 43.17%
compared with L. esculentum leaf 0.48 µg/ µg /day and 19.94% (P= 0.004;
t= 3.03, P= 0.005; t= 3.16).
It seem different feeding activity happened in the late intars larvae. The
consumption rate (CR) was 7450.23 µg/day relatively higher in S. melongena
compared with 5506.07 µg/day in L. esculentum (P= 0.21; t= 0.82). The average
growth rate (GR) showed negative values in both S. melongena and L. esculentum
leaves were -529.45 µg/day, -649.62 µg/day, respectively (P= 0.39; t= 0.28)
(Tabel 2 and 3).
Food consumption and utilization are influenced by various biotic and
abiotic factors (Reynolds and Nottingham 1985), of which the most important are
atmospheric temperature and humidity at the time of rearing (Benchamin and
Jolly 1984). Growth also depends on the digestion and utilization of food, which
varies from species to species and even between different sexes of the same
species (Rahmathulla and Suresh 2011). Ashfaq et al. 2000 stated that thickness
and leaf water contents of the leaf played a significant role in the negative or
positive responses on food consumption and utilization. According to Chapman
(1998), food quality influenced the efficiency of utilization of food. Relative
consumption rate is inherently dependent on physiological response; the
maximum amount of food was not effectively used for the development of the
body (Farrar et al. 1989).
16
E. vigintioctopunctata is a holometabolous insect which life cycle is in egg,
larvae, pupae and adult. Late fourth instar larvae E. vigintioctopunctata is the
instar just before pupae, so insect little bit or no feed on this stage and is preparing
to become a pupae. According to David (2010), pupae are the resting and non
feeding stage of wing insects, included beetle. Young or old leaf may not be
influenced feeding behavior in case of late fourth instar larvae because same leaf
has been used in case of early and late fourth instar larvae and early fourth instar
larvae shows more feeding response.
Insects, like all living organisms, require energy and nutrients for survival,
growth and reproductive activity. The nutritional components (e.g. protein,
carbohydrates, fats, vitamins, minerals) of ingested food may or may not be
digested and absorbed. The proportion of digested food that is actually
transformed into net insect biomass is denoted by ECD, the efficiency of
conversion of digested food (Lindroth 1993). In short, ECD indicate how efficient
the herbivore converts the food into a biomass. Food conversion efficiencies may
vary considerably within species. Many insects increase food consumption rates
in response to low concentrations of critical nutrient