Potential of Weeds for Ruminant Feed on Rice Fields in Java
Potential of Weeds for Ruminant Feed on Rice Fields in Java
N.R. Kumalasari1,*, E. Bergmeier1, & L.Abdullah 2
1
Faculty of Biology, University of Göttingen, Göttingen 37073, German,
*e-mail: nurrkumala@gmail.com
2
Faculty of Animal Science, Bogor Agricultural University, Bogor 16680 Indonesia
Abstract
Weeds compete with rice for sunlight, nutrients and water, and may reduce
the yield. However, in traditional rice farming systems farmers utilize many kinds
of weeds for food, forage or household purposes. Rice weeds are also utilized to
feed ruminants.The aims of this research were to explore the weed diversity of rice
field in various regions and rice farming systems in Java. Field researches were
conducted in November 2011 – January 2012. Designated research areas: West
Java: Cianjur (upland) and Karawang (lowland); Central of Java: Karanganyar
(upland) and Brebes (lowland); East Java: Malang (upland) and Gresik (lowland).
Locations of plots have been selected according the principles of stratified random
sampling. Weed assemblages were sampled in fields of intensive and extensive
farming systems as well as in fallowed areas before weeding time in two seasons.
The result showed that approximately 295 species of weeds growth in rice field
and terrace area. Dominant weed species present at the terrace in experimental
site were Cynodondactylon, Eleusineindica, and Fimbristylismiliaceae. Potency of
weed for ruminant feed gains approximately 903,5 g/m2 at terrace area.
Keywords: potency, ruminant feed, weeds diversity
Introducton
Increasng the level of rce self-suffcency of Indonesa led to an ncrease n
the ntensty of rce (Oryza sativa L.) croppng n many areas snce the 1970s. In
Indonesa, rce cultvaton covers a total of about11.5 mllon hectares throughout
the archpelago, on Java alone around 5.4 mllon hectares (Natonal Development
Plannng Board, 2003).About 70% of the area comprse rrgated rce felds, whch
have been estmated to be 100 tmes more productve than upland ran-fed rce
farmng upland rce (Farhurst and Dobermann, 2002).
One consequence of croppng ntensfcaton n rrgated systems s a shft and
an ncrease n weeds populatons. Weeds compete wth rce for sunlght, nutrents
(Nyarko and Datta, 1993) and water, and causes loss of yeld by about 10-50% (Chn
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
155
et al, 2000). Weed management therefore poses a sgnfcant challenge to Indonesan
farmng systems. Herbcde treatments change the weed communty composton
nterrelated to crop productvty (Ulber 2010). A new approach to bodversty
frendly management s therefore to enhance the benefts derved from desrable
weed speces wth hgh value for the farmer and the agroecosystem. The use of weed
speces s possbly the most effcent management to overcome problems of polluton
through herbcde usage, slow breakdown or burnng. Weed plants and vegetaton
vary enormously n morphology, phytomass and speces composton dependng on
habtat condtons and land-use (Soerjan et al., 1987). Due to ther chemcal and
physcal characterstcs weeds may or may not be grazed by rumnants. The feedng
value of rce feld weeds s lttle-known n scentfc lterature but the local farmers
have consderable knowledge whch should be combned. The man objectves of
the present study were to assess characterstcs of farmng systems n Java and to
evaluate the potental of rce weed bomass as rumnant feed.
Materals and Methods
The research was done n October 2011 untl March 2012 n lowland (0-100 m)
and upland areas (>400 m)of rce feld n Java, .e. Karawang (33 – 53 masl), Brebes
(26 – 44 masl), Gresk (14 – 41 masl), Canjur (527 – 856 masl), Karanganyar(403
– 714 masl) and Malang (526 – 684 masl). In each of the stes, sutable landscape
sectons of ca. 5 km x 5 km sze were selected and 15 plots located theren.The
weeds were sampled n cultvated areas, fallowed areas and on rce feld terraces.
Fresh bomass was measured from weed sources n each plot by placng
squareframes szed 30 cm x 30 cm. The weeds were sampled on three plots on each
rce feld and terrace n each dstrct. Weed samples were collected n each plot, cut
and weghed as fresh bomass. The samples were dred at 60°C for 48 h and weghed
as dry bomass.
Results and Dscusson
Overview
The study revealed that rce farmng systems n Indonesa are dependent on
elevaton. In upland areas contnuous water supply throughout the years facltated
weed control and reduced herbcde applcaton. Herbcdes were commonly appled
n lowland areas. The proporton of farmers who used herbcdes on ther farms
was 60% or more n the lowland areas whle less than 15% of the farmers appled
herbcdes n the upland areas (Table 1). Weed bomass source stes n upland areas
were mostly on terraces as a result of contnuous control n rce feld area whle n the
lowlands the most mportant weed bomass sources were fallows. Manual weedng
was common practce to reduce weeds n almost every rce feld area. Weedng s
156
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
Table 1. Characterstcs of rce farmng systems
Dstrct
Parameters
Herbcde
applcaton (%)
Manual weedng (%)
Tme of fallow
(weeks)
Weed bomass
source
West Java
Central of Java
East Java
Canjur
Karawang
Karanganyar
Brebes
Malang
Gresk
13.33
60
0
66.67
6.67
66.67
71.5
3-4
100
6-10
100
3-5
100
3-8
100
3-4
93.3
10-14
Terrace
Fallowed
area
Terrace
Fallowed
area and
terrace
Terrace
Fallowed
area and
terrace
usually done two tmes, specfcally 20 and 40 days after transplantng of rce plants,
wth the excepton of Gresk.
In Gresk, drect seedng was practced due to a shortage of labor and the hgher
costs of rce transplantng. Manual weedng n Gresk would commonly be done
smultaneously wth rce plant thnnng to reduce labor costs. Labor for manual
weedng s becomng ncreasngly scarce. Therefore the applcaton of herbcdes n
the frst tllage ncreases to eradcate all weeds that emerged n the tme of fallow. In
addton, poor mantenance of the rrgaton nfrastructure reduces water avalablty
for rce producton n the dry season and ncreases surface water sand floodng n
rce feld areas n the rany season.
Weed Biomass
Weed bomass s the most mportant ndcator of feed avalablty for rumnant
n rce feld area. There was a sgnfcant dfference n weed bomass among rce
feld areas, wth upland areas (Canjur, Karanganyar and Malang) producng hgher
bomass values than lowland areas (Karawang, Brebes, Gresk) (Table 2). There
were no sgnfcant dfferences between the locatons of eastern, central, or western
Java, respectvely. Fresh weed bomass n the frst rce growng season (early rany
season) yelded 891-2369 g/m2(Table 2). Weed bomass vares enormously between
regons and even between small farms n the same vllage due to dfferences of
envronmental factors and farmng management. The results showed that hgh values
of fresh weed bomass had the potental to supply rumnant feed n Java although
varablty n water regme affected the populatons and growth of weed speces.
Fresh weed bomass n Javanese rce felds dffered from that found byRoder
et al. (1998) who measured 220-990 g/m2/year of fresh weed bomass over the rce
growng season n northern Laos. There are many factors affectng the weed bomass
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
157
Table 2. Weed bomass n rce feld areas
Dstrct
Parameters
West Java
Central of Java
East Java
Canjur
Karawang
Karanganyar
Brebes
Malang
Gresk
Characterstc of
regon
Upland
Lowland
Upland
Lowland
Upland
Lowland
Fresh weght (g)
Dry weght (g)
Dry matter (%)
2369.0a
284.3a
12.0d
900.1b
140.1b
15.6a
1912.2a
245.8a
12.9c
922.3b
151.3b
16.4a
2130.7a
258.3a
12.1d
890.7b
127.5b
14.3b
Dfferent superscrpt n the same lne means sgnfcantly dfferent (P
N.R. Kumalasari1,*, E. Bergmeier1, & L.Abdullah 2
1
Faculty of Biology, University of Göttingen, Göttingen 37073, German,
*e-mail: nurrkumala@gmail.com
2
Faculty of Animal Science, Bogor Agricultural University, Bogor 16680 Indonesia
Abstract
Weeds compete with rice for sunlight, nutrients and water, and may reduce
the yield. However, in traditional rice farming systems farmers utilize many kinds
of weeds for food, forage or household purposes. Rice weeds are also utilized to
feed ruminants.The aims of this research were to explore the weed diversity of rice
field in various regions and rice farming systems in Java. Field researches were
conducted in November 2011 – January 2012. Designated research areas: West
Java: Cianjur (upland) and Karawang (lowland); Central of Java: Karanganyar
(upland) and Brebes (lowland); East Java: Malang (upland) and Gresik (lowland).
Locations of plots have been selected according the principles of stratified random
sampling. Weed assemblages were sampled in fields of intensive and extensive
farming systems as well as in fallowed areas before weeding time in two seasons.
The result showed that approximately 295 species of weeds growth in rice field
and terrace area. Dominant weed species present at the terrace in experimental
site were Cynodondactylon, Eleusineindica, and Fimbristylismiliaceae. Potency of
weed for ruminant feed gains approximately 903,5 g/m2 at terrace area.
Keywords: potency, ruminant feed, weeds diversity
Introducton
Increasng the level of rce self-suffcency of Indonesa led to an ncrease n
the ntensty of rce (Oryza sativa L.) croppng n many areas snce the 1970s. In
Indonesa, rce cultvaton covers a total of about11.5 mllon hectares throughout
the archpelago, on Java alone around 5.4 mllon hectares (Natonal Development
Plannng Board, 2003).About 70% of the area comprse rrgated rce felds, whch
have been estmated to be 100 tmes more productve than upland ran-fed rce
farmng upland rce (Farhurst and Dobermann, 2002).
One consequence of croppng ntensfcaton n rrgated systems s a shft and
an ncrease n weeds populatons. Weeds compete wth rce for sunlght, nutrents
(Nyarko and Datta, 1993) and water, and causes loss of yeld by about 10-50% (Chn
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
155
et al, 2000). Weed management therefore poses a sgnfcant challenge to Indonesan
farmng systems. Herbcde treatments change the weed communty composton
nterrelated to crop productvty (Ulber 2010). A new approach to bodversty
frendly management s therefore to enhance the benefts derved from desrable
weed speces wth hgh value for the farmer and the agroecosystem. The use of weed
speces s possbly the most effcent management to overcome problems of polluton
through herbcde usage, slow breakdown or burnng. Weed plants and vegetaton
vary enormously n morphology, phytomass and speces composton dependng on
habtat condtons and land-use (Soerjan et al., 1987). Due to ther chemcal and
physcal characterstcs weeds may or may not be grazed by rumnants. The feedng
value of rce feld weeds s lttle-known n scentfc lterature but the local farmers
have consderable knowledge whch should be combned. The man objectves of
the present study were to assess characterstcs of farmng systems n Java and to
evaluate the potental of rce weed bomass as rumnant feed.
Materals and Methods
The research was done n October 2011 untl March 2012 n lowland (0-100 m)
and upland areas (>400 m)of rce feld n Java, .e. Karawang (33 – 53 masl), Brebes
(26 – 44 masl), Gresk (14 – 41 masl), Canjur (527 – 856 masl), Karanganyar(403
– 714 masl) and Malang (526 – 684 masl). In each of the stes, sutable landscape
sectons of ca. 5 km x 5 km sze were selected and 15 plots located theren.The
weeds were sampled n cultvated areas, fallowed areas and on rce feld terraces.
Fresh bomass was measured from weed sources n each plot by placng
squareframes szed 30 cm x 30 cm. The weeds were sampled on three plots on each
rce feld and terrace n each dstrct. Weed samples were collected n each plot, cut
and weghed as fresh bomass. The samples were dred at 60°C for 48 h and weghed
as dry bomass.
Results and Dscusson
Overview
The study revealed that rce farmng systems n Indonesa are dependent on
elevaton. In upland areas contnuous water supply throughout the years facltated
weed control and reduced herbcde applcaton. Herbcdes were commonly appled
n lowland areas. The proporton of farmers who used herbcdes on ther farms
was 60% or more n the lowland areas whle less than 15% of the farmers appled
herbcdes n the upland areas (Table 1). Weed bomass source stes n upland areas
were mostly on terraces as a result of contnuous control n rce feld area whle n the
lowlands the most mportant weed bomass sources were fallows. Manual weedng
was common practce to reduce weeds n almost every rce feld area. Weedng s
156
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
Table 1. Characterstcs of rce farmng systems
Dstrct
Parameters
Herbcde
applcaton (%)
Manual weedng (%)
Tme of fallow
(weeks)
Weed bomass
source
West Java
Central of Java
East Java
Canjur
Karawang
Karanganyar
Brebes
Malang
Gresk
13.33
60
0
66.67
6.67
66.67
71.5
3-4
100
6-10
100
3-5
100
3-8
100
3-4
93.3
10-14
Terrace
Fallowed
area
Terrace
Fallowed
area and
terrace
Terrace
Fallowed
area and
terrace
usually done two tmes, specfcally 20 and 40 days after transplantng of rce plants,
wth the excepton of Gresk.
In Gresk, drect seedng was practced due to a shortage of labor and the hgher
costs of rce transplantng. Manual weedng n Gresk would commonly be done
smultaneously wth rce plant thnnng to reduce labor costs. Labor for manual
weedng s becomng ncreasngly scarce. Therefore the applcaton of herbcdes n
the frst tllage ncreases to eradcate all weeds that emerged n the tme of fallow. In
addton, poor mantenance of the rrgaton nfrastructure reduces water avalablty
for rce producton n the dry season and ncreases surface water sand floodng n
rce feld areas n the rany season.
Weed Biomass
Weed bomass s the most mportant ndcator of feed avalablty for rumnant
n rce feld area. There was a sgnfcant dfference n weed bomass among rce
feld areas, wth upland areas (Canjur, Karanganyar and Malang) producng hgher
bomass values than lowland areas (Karawang, Brebes, Gresk) (Table 2). There
were no sgnfcant dfferences between the locatons of eastern, central, or western
Java, respectvely. Fresh weed bomass n the frst rce growng season (early rany
season) yelded 891-2369 g/m2(Table 2). Weed bomass vares enormously between
regons and even between small farms n the same vllage due to dfferences of
envronmental factors and farmng management. The results showed that hgh values
of fresh weed bomass had the potental to supply rumnant feed n Java although
varablty n water regme affected the populatons and growth of weed speces.
Fresh weed bomass n Javanese rce felds dffered from that found byRoder
et al. (1998) who measured 220-990 g/m2/year of fresh weed bomass over the rce
growng season n northern Laos. There are many factors affectng the weed bomass
Proceeding of the 2nd International Seminar on Animal Industry | Jakarta, 5-6 July 2012
157
Table 2. Weed bomass n rce feld areas
Dstrct
Parameters
West Java
Central of Java
East Java
Canjur
Karawang
Karanganyar
Brebes
Malang
Gresk
Characterstc of
regon
Upland
Lowland
Upland
Lowland
Upland
Lowland
Fresh weght (g)
Dry weght (g)
Dry matter (%)
2369.0a
284.3a
12.0d
900.1b
140.1b
15.6a
1912.2a
245.8a
12.9c
922.3b
151.3b
16.4a
2130.7a
258.3a
12.1d
890.7b
127.5b
14.3b
Dfferent superscrpt n the same lne means sgnfcantly dfferent (P