Impact of Zinc Application on Growth, Yield, and Quality of African Marigold in Semi-Arid Conditions

Marigold is a widely cultivated, hardy flower crop known for its adaptability. Among the various intercultural practices in marigold cultivation, foliar application of zinc plays a critical role in enhancing yield and quality, however, standardization of this practice is necessary to optimize commercial production. Hence, the investigation aimed to standardize foliar zinc application for improving productivity in African marigold (Pusa Narangi Gainda) at Rajasthan Agricultural Research Institute, Jaipur, during 2020-21, and 2021-22. Two concentrations of zinc sulphate (ZnSO₄), Z1 (0.2%), and Z2 (0.5%), were applied at 35 and 65 days after transplanting (DAT) in a factorial randomized block design with three replications. Results indicated that Z1 (ZnSO₄ 0.2%) was most effective in increasing plant height, and promoting early bud initiation, and flower opening, while Z2 (ZnSO₄ 0.5%) significantly enhanced plant spread, primary branching, leaf dimensions, plant biomass, root-to-shoot ratio, flower diameter, and yield parameters such as flower mass and number. Z2 also improved quality traits like chlorophyll and xanthophyll content. Statistical analysis revealed significant differences among treatments, suggesting that the application of ZnSO₄ at 0.5% may be recommended for optimizing growth, yield, and quality in commercial marigold cultivation, thereby enhancing productivity and profitability.