Introduction biostimulant action is different from fertilizers (nutrient suppliers); their activity is to improve
1. Introduction biostimulant action is different from fertilizers (nutrient suppliers); their activity is to improve
Recently, pursuant to the Legislative Decree nutrient absorption efficiency, similar to hormonal
217/2006 [1], together with traditional mineral activity that allows having low concentration effects.
and organic fertilizers, new and mostly natural Their use can thus allow reducing mineral fertilization
fertilizers have been marketed, they are called doses and related fertilization costs as well as
biostimulants. These cover a wide range of synthetic
environmental impact [6-10].
organic-molecule-based materials (derived from However, information on their activity is only
vegetable extracts, seaweed, fungi or bacteria), fragmentary and stems from trials conducted with
oligosaccharides, vitamins, humic substances, different criteria and for different purposes, which are
microelements, protein hydrolysates (relatively long then hardly comparable to each other and whose
chain peptides and free amino acids). In the latter
results are quite variable.
compounds, biostimulant properties for the plants In some cases, agronomic experimentation on
seem to be basically related to fractions of smaller selected herbaceous crops has shown an increase in molecular size (< 5 kDa) as well as to free amino
yield quality and quantity by improving nutrient use acids [2, 3].
efficiency or enhancing biotic and abiotic stress As reported in some research works carried out in
resistance (drought, transplant, frost and hail) [11-13]. these last years, biostimulants are substances that
In some other cases, authors report no effect or even when applied to plants through foliar applications
negative ones on yield quantity [14]. or fertigation in addition to other fertilizer substances
Information about the activity of biostimulants on can promote and enhance plant growth and herbaceous crops is still scanty and of some of them is
development [4, 5]. However the mechanism of
reported in the following.
Supplying foliar fertilizer containing Corresponding author: Grazia Disciglio, research field:
seaweed-origin biostimulant (Fertileader 954) to soft agronomic trials. E-mail: [email protected].
Applying Natural Fertiliers to Herbaceous Crops
wheat at the boot stage gave a very positive mechanisms against biotic stress was observed, thus quali-quantitative yield results [15]. The supply of two
allowing referring these effects to a molecular basis protein-hydrolysate-based products to maize seedlings
increased leaf growth and induced morphological The use of root biostimulant (Radifarm) on changes in root architecture [16]. On the contrary, the
nursery-grown vegetable species increased root use of biostimulants caused no effect on golf course
growth and improved root/shoot ratio [22]. turf grass [17]. In another research, the use of
protein-hydrolysate-based biostimulant (Siapton 10 L) on tomato (cv Marmande) grown in high salinity
2. Materials and Methods
Starting from 2008, at the Department of conditions induced greater root growth as compared
Agriculture, Food and Environment of University of with both untreated plants and those grown in
Foggia-Italy, agronomic research activities have been non-saline conditions [18].
carried out to evaluate the use of some types of On potato crop, the use of different types of organ
biostimulants on selected herbaceous crops both in mineral products rich in amino acids caused a
the field and in pots. In this paper the authors marketable yield increase of about 1.15 t/ha as
report the results of four trials carried out over compared with the control, due to a greater and more
three years in Capitanata (Province of Foggia in homogenous tuber size and a smaller percentage of
southern Italy), on organically and conventionally rejected tubers. Instead, no influence was observed on
grown processing tomato, wheat and lettuce, by the tuber dry matter content. Also the melon crop
testing biostimulant products available on the treated with the same products showed a 33% increase
market all of them being allowed also in organic in yield and in degree °Brix of sugar as compared to
farming.
the control [19]. In a three-year period of trials on The data surveyed in each experimental trial were zucchini (cv Verde di Milano) and savoy cabbage (cv
statistically analyzed through the analysis of variance Savoy Nace and Savoy King) treated with two types
(ANOVA) and the mean values were compared using of vegetable-extract-based products with the addition
Tukey test.
of aminoacids (BF 200 and Fitocell), they generally Trial no. 1-Organically grown processing tomato: produced varying results between years. Only in one
In 2009, two elongated-fruit processing tomato year out of three there was an increase in plant growth
cultivars (Docet and Messapico), organically grown in and yield of the treated crop compared with the
the field after durum wheat, were subject to treatments control [20].
with biostimulants compared with an untreated control On some border flower species (Coleus blumei,
under standard growing techniques. The trial was Impatiens wallerana, Salvia spendens) grown in the
carried out in the area of Rignano Garganico (FG) greenhouse, supplying the biostimulant (Actiwave )
(41°35 ′08″ N, 15°30′13″ E 42 m above the sea level), through foliar application showed to induce a more
on a predominantly sandy-clay soil with skeleton rapid plant growth as expressed by larger leaf area, an
(USDA) having the following characteristics: total N increase in leaf dry and fresh weight and earlier and
(Kieldahl = 0.82‰; assimilable P 2 O 5 (Olsen) = 24 more abundant flowering compared with the control
ppm; exchangeable K 2 O (Schollemberger) = 1010 [21]. On seedlings of Arabidopsis thaliana treated
ppm; pH (water) = 7.23; organic matter (Walkley and with various concentrations of protein-hydrosylate
Black) = 1.71%.
(Siapton 10 L), increased expression of a gene pool Organomineral formulations of ERGOFITO were known to be correlated to strengthening plant defense
used. They are suspension-solutions containing
Applying Natural Fertiliers to Herbaceous Crops
humic, fulvic and crenic acids, enzymes, amino acids, ppm; pH (water) = 8.36; organic matter (Walkley and micro and macro elements and growth factors.
Black) = 1.52%.
Application time and doses of the products during the Transplanting to the field was performed on 15 growing cycle were established following the April, 2011 on previously rotary tilled soil fertilized indications provided by the supplier. The first
with 200 kg/ha of biammonium phosphate (18-46); application was performed at transplanting, by the same as in the previous trial, plant density was 4.2
soaking the seedlings into a 6% biostimulant 2 plants m . The agronomic practices usually applied in solution: subsequently, during the growing cycle,
the area were subsequently followed. formulations were applied through fertigation (no. 11
During the growing cycle, the crop was subject to events with Ergofito Alghe at a dose of 2 kg/ha each)
biostimulant treatment by foliar application at three and by foliar application (no. 4 events with Ergofito
growing stages (flowering-beginning, fruit setting and Stim at a dose of 2 kg/ha).
breaker color) compared with the untreated control. A Plant transplanting was performed in double rows
formulation based on amino acids and peptides on April 16, 2009, on a previously ploughed, rotary
obtained by chemical hydrolysis of animal epithelium tilled soil fertilized with 1 t/ha of guanito and 150
(Siapton 10 L) was supplied at the doses kg/ha of soft ground rock phosphate uniformly
recommended by the supplier (250 mL/hL per distributed on the trial surface. At transplanting, plants
application). The randomized block design with 3 were spaced in double rows 150 cm apart; plant
replicates was adopted.
spacing was 50 cm within the double rows and 30 cm At harvesting, on August 1st, the major between plants in the row, resulting in a theoretical
quantity-quality yield parameters were determined
plant density of 4.2 plants m 2 .
(plants m 2 , marketable yield, mean weight, dry matter,
A split plot experimental design with three pH, soluble solids and color of fruits). replicates was adopted, placing the fertilizer
Trial no. 3-Durum wheat:
treatments in the whole plots of 100 m 2 and varieties In the year 2010-2011, in the territory of Foggia
(Pietrafitta area) (41°26’44’’N, 15°29’34’’E and 95 m During the growing cycle, 11 irrigation events were
in the subplots of 50 m 2 with a test area of 6 m 2 .
above the sea level) a trial on durum wheat (cv
3 performed totaling a seasonal volume of 3,750 m /ha Quadrato) after fallow was performed on a silty-clay distributed through drip irrigation. Upon harvesting,
(USDA) soil having the following characteristics: on July 25, 2009, the major yield quantity components
total N (Kieldahl) = 1.3‰; assimilable P 2 O 5 (Olsen) =
31 ppm; exchangeable K 2 O (Schollemberger) = 1103 weight, dry matter, pH, soluble solids and color of
were determined (plants m 2 , marketable yield, mean
ppm; pH (water) = 7.7; organic matter (Walkley and fruits).
Black) = 2.0%.
Trial no. 2-Conventionally grown processing The crop was sown in open field on 23 December,
2 tomato: 2 2010, with 300 germinable seeds/m on 18 m plots. In 2011 another field trial was performed in the area
The biostimulant product consisting of amino acids of Ortanova (FG) (41°17 ′34″ N, 15°43′14″ E and 104
and peptides, obtained by chemical hydrolysis from m above the sea level) on conventionally grown
animal epithelium (Siapton 10 L), was administered processing tomato (cv Docet) in a silty-clay soil
through foliar application in two treatments (at (USDA) having the following characteristics: total N
tillering and tillering + heading) compared with an
(Kieldahl) = 0.63‰; assimilable P 2 O 5 (Olsen) = 212
untreated control. The applied doses were established
ppm; exchangeable K 2 O (Schollemberger) = 1598
following the supplier’s indications (4 L/ha). A
Applying Natural Fertiliers to Herbaceous Crops
randomized block design with three replicates was (540 mm/year) and predominantly concentrated in the adopted.
period from November through February. During the growing cycle, the standard practices
In 2009 trial, during the growing cycle of tomato in applied in the area were followed. At harvesting,
the area of Rignano Garganico, daily average performed on June 18, 2011 using a mini combine
temperatures gradually increased in the second
ten-day period of April (13.8 °C) until the end of July determined and, subsequently, quality parameters
harvester over a trial area of 9 m 2 , grain yield was
(26.3 °C), except a sudden drop occurring in the third (hectoliter weight), proteins, gluten and yellow index
ten-day period of June (19.3 °C), also characterized by were measured in the laboratory.
abundant rainfall (83 mm). Moreover, significant Trial no. 4-Lettuce:
rainfall was also recorded at the early stages of the In 2011 a trial was performed on lettuce (cv
growing cycle, especially in the third ten-day period Canasta/OR/ROS) grown in pots, at the Department of
of April (71 mm).
Agriculture, Food and Environment, University of In 2011 trial, in the area of Ortanova, during the Foggia (41°27’27’’N, 15°31’56’’E and 75 m above
growing cycle of tomato, daily average temperatures the sea level). The crop was transplanted on April 7,
gradually increased from about 14.2 °C in the second 2011 on a sandy-clay soil (USDA) having the
ten-day period of April until 25.1 °C in the last following characteristics: total N (Kieldahl) = 0.81‰;
ten-day period of July. Total monthly rainfall was asssimilable P 2 O 5 (Olsen) = 86 ppm; exchangeable
equal to 52, 28, 6.5 and 74.5 mm, respectively in the K 2 O (Schollemberger) = 1430 ppm; pH (water) = 8.14;
months of April, May, June and July. organic matter (Walkley and Black) = 1.30%, after
In the year 2010-2011, in Foggia area, during the basic mineral fertilization equivalent to 100 kg/ha of
growing cycle of wheat ten-day period daily average N; 60 kg/ha of P 2 O 5 and 20 kg/ha of S. Afterwards,
temperature decreased from 7.1 °C at the beginning of top dressing was performed with 70 kg/ha of N.
the cycle in December 2010 to 5.9 °C as an average in
A crop receiving the same biostimulant product January 2011, and then gradually increased up to (Siapton 10 L) by foliar application (250 mL/hL) at
21.3 °C in the early ten-day period of June. Total three different time periods of the growing cycle (on
rainfall during the whole cycle was equal to 430 mm April 18, 1 and 15 May) was compared with the
with peaks of about 110 and 109 mm, respectively, in untreated control.
the third ten-day period of January and in the first The randomized block design with 5 replicates was
ten-day period of March 2011. Also for lettuce, grown adopted. At harvesting, on June 8, 2011, the
in Foggia area, daily average temperatures during the quantity-quality yield components were determined:
growing cycle increased from 14.8 °C in the first
2 marketable head weight, number and surface (cm ) of ten-day period of April to 26.4 °C at the end of the total and edible leaves, dry matter (%), nitrate content
cycle early in June. Total rainfall during the whole
(% and mg/kg of dry leaves) and leaf thickness as
cycle was 48 mm.
specific leaf area per dry leave weight (cm 2 /g) .