Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis

Abstract

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances.

Plant- and Seaweed-Based Extracts Increase Yield but Differentially Modulate Nutritional Quality of Greenhouse Spinach through Biostimulant Action

“…The concentrations of the three commercial PBs used were based on the manufacturers' recommendations as well as on previous published work [21,28,29].…”

“…A presumed mechanism behind the plant-growth stimulation effect is the presence of signaling molecules such as small peptides which are typical components of the commercial PH Trainer ® used in the current experiment. The bioactive peptides in the Trainer ® formulation could act as elicitors since they are easily received by both leaf and root, thus may have triggered a signal transduction pathway through modulation of endogenous phytohormone biosynthesis (auxin-and/or gibberellin-like activities; [28,37]) thus boosting crop yield. Another putative mode of action behind the stimulation effect of legume-derived PH on fresh yield is the modulation of the root system architecture in particular the increase in root hair length and density [38], which may improve N use efficiency, thus boosting total fresh and dry biomasses.…”

“…The ability of PH containing free amino acids and peptides to avoid accumulation of nitrates in leaf tissue could be associated to an up-regulation of the key nitrogen assimilation genes like nitrate reductase, thus contributing to a higher assimilation of nitrates into amino acids [49]. soluble peptides [2,16]; (ii) the greater uptake, translocation and accumulation of nutrients effecting stimulation of the root system architecture [18,28]; and (iii) the expression of genes encoding for macronutrients transporters in cell membranes [37,47]. From a botanical point of view, spinach, which belongs to the Chenopodiaceae family, is normally considered a nitrate-accumulating leafy vegetable species [48].…”

Innovative bio-products for agriculture

“…Colla et al [27] studied biostimulant action of protein hydrolysate containing amino acids and small peptides derived from plant by enzymatic hydrolysis. Hormonelike activity, nitrogen uptake, and growth stimulation were investigated in terms of biostimulant action on corn, tomato and pea.…”

Analyzing the Environmental Impact of Chemically-Produced Protein Hydrolysate from Leather Waste vs. Enzymatically-Produced Protein Hydrolysate from Legume Grains

“…As defined by the European Biostimulants Industry Council [3], plant biostimulants contain microorganism(s) and/or substance(s) whose function, when applied to plants or the rhizosphere, is to stimulate natural processes to enhance/benefit nutrient uptake, nutrient efficiency, tolerance to abiotic stress, and crop quality [4][5][6]. Protein hydrolysate-based biostimulants contain free amino acid, oligo and polypeptides achieved through enzymatic and/or chemical hydrolysis of proteins, especially from vegetal or animal sources [7][8][9][10][11][12][13].…”