Biostimulant-induced drought tolerance in grapevine is associated with physiological and biochemical changes

Abstract Background In this research, the effects of exogenous application certain biostimulants [amino acid (AA), humic (HA), fulvic (FA), and seaweed extract (SE)] on fruit yield quality, leaf mineral contents, some critical physio-chemical characteristics grapevine ( Vitis vinifera L.) cv. ‘Yaghouti’ were investigated under well-watered (WW) drought-stressed (DS) conditions. Results Drought stress caused a remarkable reduction in weight 20 berries yield, meanwhile marked increase titratable acidity (TA) total soluble solid (TSS) content fruits. Application biostimulants, especially SE, enhanced berries, TSS content, decreased TA fruits DS vines. Although drought had negative effect chlorophyll grapevine, was alleviated by SE. Moreover, made accumulation abscisic (ABA), proline, phenol, carbohydrates, level hydrogen peroxide (H 2 O ) malondialdehyde (MDA), as well activity guaiacol peroxidase (GPX) catalase (CAT) enzymes increased leaves. further ABA, carbohydrates antioxidant enzymes, but reduced MDA H Under conditions, concentrations N, P, K increased, Fe Zn decreased; however, grapevines treated with SE accumulated higher these nutrients than CON Conclusion sum, evidenced study results, have high potential for promoting quality drought-prone regions.