Use of Biostimulants for Reducing Nutrient Solution Concentration in Floating System

Abstract

The production innovations have been evolving more and more towards organic, sustainable or environmental friendly systems. Contemporarily, the yield and the quality of crops must be assured. The reduction of fertilisers may be obtained by improving the nutrients uptake or their utilisation by the plants. The aim of our work was to verify if the progressive reduction of nutrient solution concentration in the floating system can be compensated by applications of a biostimulant (Actiwave®, Valagro S.p.a.) without compromising the yield and the quality of vegetables. The experiments were performed on rocket (Eruca sativa Mill.) grown in floating system with standard nutrient solution (NS100%), which was compared with nutrient solutions diluted 4 (NS25%) or 10-fold (NS10%) with or without 0.3 ml L-1 Actiwave. At harvest, yield, leaf area, root dry weight, chlorophyll, carotenoids, and leaf nitrate content were determined. Results showed that Actiwave significantly increased the nutrient uptake and nutrient use efficiency in all treatments. In fact, no statistically significant differences were found in yield between NS100% and NS25% plus 0.3 ml mL-1 Actiwave. Moreover, Actiwave reduced the leaf nitrate content and increased chlorophyll and carotenoids in all treatments. Our results indicate that Actiwave lowered the leaf nitrate content through its ability in stimulating nutrient uptake and nitrogen metabolism. The combination of hydroponics and biostimulants appears as a promising environmental friendly strategy for the greenhouse production of highquality vegetables.

Effect of compost on antioxidant components and fruit quality of sweet pepper (capsicum annuum L.)

“…These results led us to presume that pepper plants may utilise benefits from compost fertilizer for their protein synthesis and growth development. On the other hand, organic acids and organic fertilizers (compost) act as precursors or activators of phytohormones and growth substances and secondary compounds in plants (Vernieri, et al, 2006). Moreover, But because there was sufficient light for normal photosynthetic rates in our experiment, the extra C could have been allocated for synthesis of C-based secondary compounds like phenolics in plants treated with the organic fertilisers Toor, et al, 2006).…”

Synergistic effect of Chryseobacterium gleum sp. SUK with ACC deaminase activity in alleviation of salt stress and plant growth promotion in Triticum aestivum L.

“…Feathers are rich and cheap source of proteins and may function as effective biofertilizer; this fact is responsible for interest of many researchers to prepare feather-based biofertilizer (Tiwary and Gupta 2010). Feathers can be degraded by bacteria and formed lysate having amino acids and peptides can be used as biostimulant to increase nutrient uptake, growth of plants as well as to tolerate abiotic and biotic stress to increase overall crop yield (Vernieri et al 2006). The degraded feather lysate could generate tryptophan in appreciable amount which is precursor of plant hormone IAA (Tsavkelova et al 2012).…”

Natural biostimulants reduce the incidence of BER in sweet yellow pepper plants (Capsicum annuum L.)

“…These products, varying in chemical composition, are proprietary and can be applied at different growth stages of plants. They often contain mixture of organic and inorganic compounds including essential macro-and micronutrients, humates, polysaccharides, amino acids, carbohydrates, glycosides and plant hormones (Adani et al 1998, Maini 2006, Vernieri et al 2006, Tuteja 2007, Mora et al 2010. Most of the biostimulants are completely environment and health friendly.…”

“…They increase plant mineral uptake and improve the nutrients use efficiency. Thus, several benefits for plants were identified and reported from biostimulants: increased root and shoot growth, increased resistance to stress, and increased water uptake; any of which would reduce transplant shock (Adani et al 1998, Maini 2006, Vernieri et al 2006, Tuteja 2007. Their effect is a result of many components that may work synergistically at different concentrations (Vernieri et al 2005).…”