Physiological, Anatomical, and Agronomic Responses of Cucurbita pepo to Exogenously Sprayed Potassium Silicate at Different Concentrations under Varying Water Regimes

Drought is one of the major environmental stresses that devastatingly impact squash development, growth, and productivity. Potassium silicate can attenuate injuries caused by water stress. Hence, this study was designed to investigate influence three concentrations potassium silicate; 10, 15, 20 g/L on plants versus untreated control under irrigation regimes; 100, 75, 50% estimated crop evapotranspiration (ET). The obtained results indicated moderate (75% ET) or severe (50% drought stress conditions gradually declined photosynthetic pigments, relative content (RWC), mineral content, physiological parameters, anatomical characteristics. These deleterious impacts were reflected all growth yield traits, i.e., plant height, fresh dry weight root shoot, fruit yield. On other hand, antioxidant enzyme activities; superoxide dismutase (SOD), catalase (CAT), peroxidase (POX) significantly increased at ET followed 75% ET. However, evaluated exogenous applications substantially enhanced RWC, N, P, K activities, characters (periderm thickness, cortex midrib mesophyll number xylem vessels per main vascular bundle, thickness collenchymatous tissue upper epidermis, lower epidermis). desirable in enhancing parameters. Conclusively, alludes exogenously applied silicate, particularly g/L, alleviate effects enhance productivity plants, especially arid environments.