Physiological Effects of Immunostimulant (Zerox) on Seed Germination and Early Seedling Development of Cotton (Gossypium Hirsutum L.) Under Laboratory and Field Conditions

Seed germination is a critical stage determining crop establishment and productivity, particularly in cotton ( Gossypium hirsutum L.) grown under variable environmental conditions. The present study aimed to evaluate the dose-dependent effects of a colloidal silver-based immunostimulant (Zerox) on seed germination and early seedling development under both controlled laboratory and field conditions. Cotton seeds of the Bukhara-10 variety were treated with five different application rates of Zerox (1.0, 1.5, 2.0, 2.5, and 3.0 l/t), along with a standard treatment (Fitovak, 200 ml/t) and a control (water). Laboratory experiments were conducted under controlled temperature (26 °C) and humidity conditions, while field trials were carried out over three consecutive growing seasons. Germination dynamics, seedling emergence, and early growth parameters were systematically recorded. The results demonstrated a significant improvement in germination performance in response to Zerox application. The optimal treatment (2.0 l/t) resulted in 100% germination under laboratory conditions and significantly enhanced field germination (90.3%), representing a 17.7% increase compared to the control. Moreover, treated seeds exhibited accelerated germination, with emergence occurring approximately three days earlier than untreated seeds. The observed effects are associated with enhanced enzymatic activity, improved mobilization of seed reserves, and regulation of endogenous phytohormones, particularly auxin and cytokinin. These findings suggest that Zerox acts as an effective physiological modulator, promoting rapid and uniform germination. Overall, the application of Zerox at an optimal dose (2.0 l/t) can be recommended as an efficient seed treatment strategy to improve cotton establishment under both laboratory and field conditions.