Foliar application of Zinc and Boron improved physiological traits, productivity and shelf life of onion

Micronutrients play a crucial role in enabling crops and vegetables to achieve optimum productivity, improve storage quality, and overcome physiological disorders. The present study focuses on evaluating the effects of the foliar application of Zinc, Borax, and their combined application in enhancing onion yield and shelf life of Allium cepa L. (cultivars Red coral and Liberty). An experimental study was conducted for two years at Agriculture Research Unit, DIHAR Leh (34.1383 & ring;N, 77.5725 & ring;E) to assess the impact of different doses of ZnSO4, Borax, and their combination on onion yield and shelf-life improvement. Four treatments of ZnSO4 and Borax (T-1: 0.5% ZnSO4; T-2: 0.25% Borax; T-3: 0.5% ZnSO4 + 0.25% Borax and T-4: control) were applied twice, once at 30 DAT and again after 45 DAT. Among four treatments, T-3 showed a significant impact on growth parameters, yield, and onion shelf-life followed by T-1 and T-2 compared to the control T-4 treatment. Foliar sprays of ZnSO4 and Borax, rather than only ZnSO4 or Borax application, significantly improved plant height, leaves number, leaf area index, chlorophyll content, and onion yield. The storage examination revealed an important correlation between the concurrent application of ZnSO4 and Borax on onion, demonstrating a significant reduction in weight loss, an increase in Total Soluble Solids (T.S.S), and an extension of the onions' shelf life. These findings hold the potential for significant implications in elucidating the optimal utilization of micronutrients for improving onion cultivation and preservation practices in cold desert regions of Ladakh.