Compost sterilization was mainly carried out in protected crop system. Concerns about widespread use of chemicals/pesticides and their effect on human health and environment have prompted the use of heat as an alternative method of sterilization. Continuous cropping of monocultures or different host crops needs to be sterilized after each cropping. The current study was designed to analyze the effect of sterilization on nutritional components and compost biota. The present study revealed that various temperatures have different effect on compost biota. Among ten tested temperature and time levels, T10 (110⁰C/60min) was found best for controlling microbial biota with less than 30 bacterial colonies and no fungal colony per petri plate, while T2 (70⁰C/30min) was observed to be least effective in controlling soil biota. Analysis of variance for pre and post-compost showed significant not differences in pH and electrical conductivity. However, pH and EC slightly increased after sterilization. Significant variations were observed in organic matter contents of pre (25.86 %) and post sterilization (18.3%) at 110 ⁰C for 60 minutes. Lime content was slightly increased with sterilization as compared to the unsterilized compost sample. Analysis of nitrogen, phosphorous and potassium levels showed significant variations in pre and post sterilization samples, while non-significant variations at different temperatures. Maximum concentration of nitrogen was recorded at 90⁰C/30 minutes (1 mg kg ^-1) while the lowest (0.43 mg kg ^-1) recorded at 110 ⁰C/60 minutes. Similarly, the highest levels of phosphorous and potassium was recorded at 90⁰C/45 min (3.1 mg kg^-1) and 90⁰C/60 min (271.3 mg kg^-1).

Keywords:  Soil microbes; Organic matter; Nutrients; Time duration; Temperatures