INFLUENCE OF DIFFERENT SEASONS AND TECHNIQUES ON THE YIELD AND QUALITY OF VERMICOMPOST USING UNDER SUBTROPICAL CONDITIONS OF INDIA

Abstract

In order to investigate the effect of different seasons and methods on vermicompost production, 200 kg cow dung (Gobar, 10-15 days old) was used in triplicate for estimating production indices (days of preparation, yield, recovery, etc), quality of final product (Nitrogen (N), Phosphorus (P), Potassium, Organic Carbon (OC), etc), worm morphometry (length of worms, number of worms in kg raw vermicompost, etc) and economics. The experiment was laid at randomized block design (RBD) comprising of sixteen treatment combinations replicated thrice. The treatment comprises of four seasons viz. December-February (S₁), March-May (S₂), June-August (S₃) and September –November (S₄)  and of four preparation techniques viz., heap method (Kaccha floor; beneath tree shade; covered by gunny bags) (T₁), heap method (Pacca floor; covered by gunny bags) (T₂), standard vermicompost shed (with shade; covered by gunny bags) (T₃) and standard vermicompost shed (without shade; covered by gunny bags) (T₄). A routine standard procedure of vermicompost production was used amongst all treatment groups except for nominal variations depending upon different seasons. The results revealed that among seasons June-August (S₃) significantly recorded quicker decomposition (61.08+3.29 days) leading to higher compost yield (109.89±1.66 kg), recovery percentage (54.94±1.92) with more quality in terms of per cent N (1.43±0.04),K (0.96±0.05), OC (16.40±0.41) carbon nitrogen ratio (11.52±0.10) with better earthworm studies of highest population of earthworms/kg (176.42±17.56/kg), total worms/lot (19598.33±2086.36) kg worms in total vermicompost (13.07±1.39) maximum length of earthworms (8.22±0.48 cm) and higher total income (Rs. 7411.93±705.31),net returns (Rs. 5049.93±694.07) and Benefit cost ratio (B:C) ratio (2.12±0.29). Whereas among techniques standard vermin compost shed (with shade; covered by gunny bags) (T₃) produced more vermicompost (104.25±2.06) with more recovery percentage (52.13±1.62) and faster vermin compost (71.50±8.02 days) enriched in N (1.53±0.01), P (0.60±0.01), K (1.09±0.01),      OC  (17.72±0.15) and C:N ratio (11.57±0.08) with maximum earthworms/kg (217.33±4.79 kg), more total worms/lot (22754.13±917.68) and kg worms in total vermi compost (15.17±0.61) with their maximum length (10.28±0.16 cm). Further this technique is also more remunerative (rupees) in terms of total income (8418.72±321.92), net returns (6070.72±306.76) and B:C (2.58±0.11).