Enhancement of Growth and Physiological Parameters of Marigold (cv. 'Bidhan-2') through Hydrogels, Calcium Ammonium Nitrate (CAN), and Sodium Nitroprusside (SNP) during Hot Summer Conditions in Rayalaseema Region of Andhra Pradesh, India

Marigold (Tagetes erecta L.) is a popular ornamental flower known for its vibrant colors and pleasant fragrance. To enhance its growth and productivity, various agricultural inputs like hydrogels, calcium ammonium nitrate (CAN), and sodium nitroprusside (SNP) have been employed in this study. The present research investigates the impact of these treatments on growth analysis parameters such as Crop growth rate, Relative growth rate, Net assimilation rate and Specific leaf weight in marigold cv. 'Bidhan-2' over a two-year experimentation period (2019-2021) at College of Horticulture, Dr. Y.S.R Horticultural University, Anantharajupeta, Annamayya district of Andhra Pradesh. The experiment consisted of 12 treatments, laid out in factorial randomized block design with three replications under open field condition. Significant variations were observed among different treatments with respect to growth analysis parameters. The results highlight the positive influence of Pusa hydrogel on Crop Growth Rate (CGR) and the benefits of applying 50% nitrogen in the form of calcium ammonium nitrate (CAN) to stimulate Net Assimilation Rate (NAR). The complex interplay among moisturizing agents, the concentration of CAN and the timing of sodium nitroprusside (SNP) application, offering insights into the intricate mechanisms that influence Specific Leaf Weight (SLW).