COMBINED EFFECT OF VERMICAST-TRICHODERMA-SAWDUST ON KALE, SWISS CHARD, AND PAK CHOY GROWTH
Nowadays, organic amendment has been used to address soil fertility problems and improve crop production. Vermicast-sawdust mixed plant growing media are low-cost and rich in beneficial microbes and essential nutrients but not extensively studied. The present study focused on confirming the best of vermicast-Trichoderma-sawdust combination. The mixed proportion of the vermicast-sawdust comprised (1) 80% vermicast+20% sawdust; (2) 60% vermicast+40% sawdust; (3) 40% vermicast+60% sawdust; (4) 20% vermicast+80% sawdust; and (5) sawdust alone (control) added without or with 10^5 spores/g Trichoderma viride. The nutrient-release pattern and mineralization analysis suggested that more vermicast leads to more nutrient-release pattern speed and minerals, and T. viride in the growing media did not show a positive effect. Active microbial community structure showed the mixed media with the 40% vermicast-60% sawdust or the 60% vermicast-40% sawdust gave the highest diversity of active microbial community composition and the highest overall mineral nutrients content compared to the other media. The40% vermicast+60% sawdust mix media was the best combination media on the growth and development of three different microgreen plant species, kale (Brassica oleraceae var. sabellica L.), Swiss chard (Beta vulgaris Subspecies Maritima), and pak choy (Brassica rapa ssp. Chinensis).