Impact of humic acid and seaweed biostimulants on growth, yield and quality of sweet potato (Ipomoea batatas L.) cv. CO 34

The field experiment was conducted to evaluate the effects of humic acid and seaweed biostimulants on the growth, yield and quality of sweet potato (Ipomoea batatas L.) cv. CO-34 during the rabi season of 2020-21 at the Vegetable Farm, Department of Vegetable Science, College of Horticulture and Forestry, Jhalrapatan City, Jhalawar, India. The study employed a factorial randomized block design with three replications, testing twelve treatment combinations of humic acid (0, 10, 20, 30 ml L–1) and seaweed extract (0, 1, 2 ml L–1). The combination of 30 ml L–1 humic acid and 2 ml L–1 seaweed extract (H3S2) significantly enhanced growth parameters, including vine length (62.63 cm at 60 DAT, 126.16 cm at 120 DAT) and number of branches per vine (10.33 at 60 DAT, 22.50 at 120 DAT), as well as yield parameters such as tuber number per plant (6.77), tuber weight (242.67 g) and tuber yield (46.10 t ha–1). Quality parameters, including total soluble solids (18.47 °Brix), dry matter (29.21%) and ascorbic acid content (18.40 mg 100 g–1), were also maximum in H3S2 compared to the control (H0S0). These findings underscore the synergistic potential of humic acid and seaweed biostimulants in improving sweet potato productivity and quality, offering valuable insights for sustainable agriculture.