Vol. 11, Issue 10 (2022)

Author(s):
Manonmani S, Senthilkumar S and Manivannan S

Abstract:
A plant biostimulant is any substance or microorganism applied to crop or soils with the aim to enhance nutrition efficiency, abiotic stress tolerance and/or crop quality traits regardless of its nutrients content. Major categories of plant bio-stimulants are humic and fulvic acids, protein hydrosylates, seaweed extracts, botanicals, chitosan and other biopolymers, inorganic compounds and beneficial micro-organism. Humic acid increases the antioxidation capacity under several abiotic stresses and up regulates the biosynthesis of defense-related secondary metabolites. Drenching of humic acid (300 ppm) in nutrient solution could be used as a suitable strategy to maintain growth and yield of strawberry under salinity. (Saidimoradi, et al., 2019). Protein hydrolysate stimulates phenylalanine ammonia lyase (PAL) enzyme and production of flavonoids under salt stress. Seaweeds can be used as source of organic matter and as fertilizer. They improve mineral composition of plant tissues especially micro nutrient viz., Fe, Zn, Mg, Cu. Similarly, NSKE a plant based extract reduce T. semipenetrans population by 56.8–58.1% in soil and 46.4–56.2% in root. (Nagachandrabose, et al., 2021). Microbial biostimulant-induced plant growth enhancement through the improvement of biological N2 fixation, solubilization of minerals and other nutrients and increasing plant access to soil nutrients help to reduce the yield gap under adverse environmental conditions. PGPR increases the root foraging capacity and enhance the nutrient use efficiency when they applied to plants. Likewise, foliar application of humic acid @ 60 ml/L during bud burst stage and soil application of bio-inoculants (PSB and A. chroococcum @ 10 ml/plant) along with 80% RDF of NPK increase the vegetative growth traits, flowering, fruit yield and quality. (Ashwini, et al., 2022).