Soil carbon, microbial biomass carbon, soil health and productivity of toria (Brassica campestris L.) crop as affected by the application of organic manures

Aim: To investigate the effect of different organic manures on the performance of toria crop and to understand their impact on the soil properties and availability of nutrients in acidic sandy loam soil. Methodology: Three-year fixed plot study was conducted with 7 treatments viz., T-1: control, T-2: recommended dose of fertilizers (RDF), T-3: cow dung manure @ 5 t ha(-1) , T-4: pig dung manure @ 5 t ha(-1), T-5: goat dung manure @ 5 t ha(-)1 , T-6 : farm yard manure (FYM) @ 5 t ha(-1) , and T-7 : vermicompost @ 5 t ha(-1) replicating 3 times in a complete randomized block design. Data were collected and analysed following the standard procedures. The yield and yield attributing parameters of toria and the soil properties such as soil pH, organic carbon, microbial biomass carbon and available NPK were studied. Results:Application of different organic manures significantly affected the plant height, number of primary branches per plant, number of siliquae per branch, number of seeds siliqua and 1000-seed weight of toria crop. Addition of organic manure significantly enhanced the soil organic carbon, microbial biomass carbon and available NPK in the soil over initial, except soil pH. The cost of cultivation, gross return and net return varied from 10.50 x 10(3) to 23.10 x 10(3), 15.00 x 10(3) to 35.10 x 10(3) and 4.46 x 10(3) to 19.96 x 10(3) Rs. ha(-1), respectively. The B:C ratio varied in the order of goat dung manure > cow dung manure >RDF >FYM > pig dung manure > vermicompost > control treatment. Interpretation: nourishment of soil quality and health, application of vermicompost was confirmed to be the best over other organic sources of nutrients primarily due to enhancement in C and N status and an increase in microbial activities in soil.