INFLUENCE OF FOLIAR ORGANIC FERTILIZER DERIVED FROM SPENT SUBSTRATE OF CORDYCEPS MILITARIS ON THE GROWTH AND YIELD OF BOK CHOY (Brassica rapa subsp. chinensis)

This study aimed to evaluate the potential of Cordyceps spent substrate-derived foliar organic fertilizer on the growth and yield of bok choy under field conditions. The experiment consisted of five treatments, including a negative control and a positive control, arranged in a randomized complete block design with three replications. The results indicated that growth parameters, including plant height, the number of leaves, and canopy diameter, did not differ significantly (p > 0.05) among treatments. However, significant differences (p < 0.05) were observed in the average individual weight and the yield per 2 m² plot. Compared with the negative control, plot yields in the Cordyceps spent substrate-derived foliar organic fertilizer treatments increased by 11.4% in Cordyceps spent substrate-derived foliar organic fertilizer 1 (lowest dose) and up to 49.0% in Cordyceps spent substrate-derived foliar organic fertilizer 3 (highest dose). Notably, the individual weight of bok choy plants and the yield per 2 m² plot obtained from the high Cordyceps spent substrate-derived foliar organic fertilizer doses (20 and 40 mL L⁻¹) were comparable to those obtained with the commercial fish fertilizer treatment. These findings suggest that Cordyceps spent substrate-derived foliar organic fertilizer has strong potential as a foliar biofertilizer for improving the yield performance of leafy vegetables.