INFLUENCE OF COMPOSTING METHODS ON COMPOST MATURITY AND QUALITY

An investigation entitled Influence of composting methods on compost maturity and quality was conducted at Plant Propogation and Nursery Management Unit, Vellanikara to study the effect of composting methods on compost maturity and quality and to evaluate the suitability of compost obtained from various composting methods as organic manure on the growth and yield performance of Okra crop. The experiment on influence of composting methods on maturity and stability parameters of compost consisted of eight methods of composting (T₁-Aerobic composting using cow dung, T₂- Aerobic composting using Bacillus subtilis (KAU culture), T₃- Composting using effective microorganisms, T₄- Composting with Trichoderma and worms, T₅ - Vermicomposting, T_6- Varanashi composting, T₇- Heap and T₈- Pit method of composting). The experiment to evaluate the suitability of compost as organic manure in the performance of Okra crop consisted of nine treatments including compost obtained from all the composting methods and farm yard manure. The organic manure requirement of the crop was substituted by compost and the quantity was decided in comparison to nitrogen content of farm yard manure (FYM) requirement of Okra (12t/ha). Results of the study indicated that compost obtained from all the composting methods helped to attain physical, chemical and biological parameters of compost maturity at varying degree. The highest yield was recorded in Varanashi composting followed by aerobic compostingusing cow dung. Based on the recovery percentage, the highest compost recovery was noticed in aerobic composting using cowdung. The nutrient content of compost obtained from all the composting methods was in the permissible limit. Even though the quantity of compost produced was less using microbial culture, compost produced has attained all the maturity parameters. Hence in the absence of cowdung, composting using Bacillus subtilis (KAU culture) and Trichoderma and worms can be used as substitute for cow dung. Germination studies using compost extract and compost as potting mixture revealed that the compost produced were not phototoxic in nature and also the heavy metal content were in the permissible limit. Based on the compost yield and better parameters of maturity, aerobic composting, varanashi composting and vermicomposting was found superior. Crop performance was significantly higher with varanashi compost, vermicompost and compost using EM. There was a positive and sgnificant increase in available soil nutrient content after the addition of all the compost.