MSc

One of the important factors affecting the successful use of compost for agricultural purpose is compost maturity because immature compost can be detrimental to plant growth and soil environment. Compost obtained from many of the rapid methods is found to be coarser and need to be evaluated for maturity and quality prior to its agricultural use. Although the practical applicability and benefits of composting methods are widely known, there has been very limited effort towards scientific documentation and evaluation of the biodegradation process, along with quality evaluation of its end product and post application efficiency. The present study was proposed against this backdrop to study the influence of various composting methods on its end product quality, particularly in terms of its stability and maturity status and to evaluate whether the compost obtained from these methods can be directly used as manure. An investigation entitled ‘Influence of composting methods on compost maturity and quality’ was conducted at Plant Propogation and Nursery Management Unit, Vellanikkara to study the effect of composting methods on compost maturity and quality and evaluate the suitability of compost obtained from various composting methods as organic manure on the growth and yield performance of bhindi crop. The experiment consisted of eight methods of composting (T1-Aerobic composting using cowdung, T2- Aerobic composting using Bacillus subtilis (KAU culture), T3- Composting using effective microorganisms, T4- Composting with Trichoderma and worms, T5 - Vermicomposting, T6- Varanasi composting, T7- Heap and T8- Pit method of composting). The 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 varanasi composting followed by aerobic composting using cowdung. 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.
In the absence of cowdung, composting using Bacillus subtilis (KAU culture), and Trichoderma and worms can be used as substitute for cowdung. Germination studies using compost extract and compost as potting mixture revealed that the compost produced were not phototoxic in nature and the heavy metal content was in the permissible limit. Based on the compost yield and better parameters of maturity, aerobic composting, varanasi composting and vermicomposting were found superior. The experiment to evaluate the suitability of compost as organic manure in the performance of bhindi crop consisted of nine treatments including compost obtained from eight different composting methods and farm yard manure. The organic manure requirement of the crop was substituted by compost and the quantity was decided based on nitrogen equivalent basis of farm yard manure requirement of bhindi (12t/ha). Crop performance was significantly higher with varanasi compost, vermicompost and compost using effective microorganisms. There was significant increase in available soil nutrient content after the addition of compost as compared to the initial content in all the treatments.