Effect of long term application of FYM and Vermicompost on soil carbon pool, enzymes and microbial activities in Pearl millet-chickpea cropping sequence after 6^th crop cycle

The field experiment was carried out on a fixed site at the research farm of Bajra Research Scheme, College of Agriculture, Dhule, Maharashtra, India which was initiated during 2013-2014. The experiment was laid out in randomized block design with eight treatments replicated three times. Treatments for pearl millet composed of T1: Control, T2: 100% recommended dose of fertilizer through inorganic fertilizers, T3: 100 % recommended dose of nitrogen through farm yard manure, T4: 100 % recommended dose of nitrogen through vermicompost, T5: 50 % recommended dose of nitrogen through farm yard manure + 50 % recommended dose of nitrogen-through vermicompost, T6: 5-ton farm yard manure ha-1, T7: 3-ton vermicompost ha-1 and T8: 2.5-ton farm yard manure ha-1 + 1.5-ton vermicompost ha-1). However, treatments for chickpeas are composed of T1: Control, T2: 100% recommended dose of fertilizer through inorganic fertilizers, T3 to T8: residual effect of farm yard manure, and vermicompost alone and in combinations. The experimental soil was alkaline, calcareous, clayey in texture, low in available nitrogen and phosphorus and high in available potassium. The continuous application of the 100 % recommended dose of nitrogen through farm yard manure for 6 years to pearl millet showed improvement in organic carbon fractions, soil enzyme activity, soil microbial population, and pearl millet equivalent yield. This treatment was followed by the application of 50 % recommended dose of nitrogen through farm yard manure + 50 % recommended dose of nitrogen through vermicompost.