Effect of plant growth regulators on morphology and physiology of Withania somnifera (L.) Dunal

Several organic compounds are referred to as plant growth regulators (PGRs) that influence the differentiation, growth and development of plants when they are applied in small concentrations. The present study aims to evaluate the effect of Indole 3-acetic acid and Gibberellic acid on the morphological and physiological traits of Withania somnifera (L.) Dunal. It is among the most crucial plants, utilized in Ayurvedic medicines and traditional healthcare systems since time immemorial. One month old plants of W. somnifera were transferred to the plastic pots and left to adapt for 15 days. Thereafter, both plant growth regulators at 25 mg/L, 50 mg/L, and 100 mg/L concentrations were exogenously sprayed on the leaves and stems of the 45 days old plants after the regular interval of 15 days for 90 days. Various concentrations of 20 mL were administered to each plant. Plants used as control were treated with distilled water. Sampling was done after 30, 60 and 90 days of treatment. Applications of plant growth regulators resulted in enhancements in root and shoot length, number of leaves, leaf area, fresh and dry weight, and carbohydrate and protein content of the plant.