Recycling of agricultural wastes to vermicomposts: Characterization and application for clean and quality production of green bell pepper (Capsicum annuum L.)

Abstract

With increasing agricultural production after green revolution in India, generation of agricultural waste is a concern for clean agricultural production system. The purpose of the study is to recycle locally available agricultural wastes into vermicompost and apply it on crops. In this study vermicomposts prepared from combinations of four sources of each plant biomass and animal excreta were characterized and tested for yield and quality of green bell pepper (Capsicum annum L.). Vermicompost samples were analyzed for macronutrients, micronutrients and enzymatic activities at intermediate (40 d) and final (80 d) stages of decomposition. During composting, total organic carbon content of the bedding material decreased and C: N ratio was narrowed down. Zinc, Cu, and Mn contents were decreased by 6.9–177.3%, 28.5–318.5% and 0.7–207.4%, respectively, while Fe content increased by 15.4–64.3% in the matured samples. Acid phosphomonoesterase and dehydrogenase activities were reduced by 2.5–26.0% and 15.5–84.1%, respectively; while the β-glucosidase activity of vermicompost from cow dung and pig dung was increased by 2.0–30.7% at maturity. Application of vermicompost along with NPK fertilizers enhanced morphological, biochemical and yield attributes of green bell pepper which in-turn improved yield (7.1–135.7%) over the control. Vermicomposts also improved soil fertility by increasing organic C and plant-available N, P and K. Hierarchical cluster analysis revealed that the properties of mature vermicomposts were mainly determined by the animal excreta. Poultry litter along with paddy straw and Azolla pinnata proved to be superior raw material in the production of high quality vermicompost which could produce good quality and quantity of fruits. The study also suggests that production of vermicompost from locally available plant biomass and animal excreta will sustain crop harvest with quality produce and improve soil fertility.