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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
A field study was carried out on Alluvial soils of Varanasi to analyse the short term impacts of replacing mineral by organic fertilizers on the physico-chemical properties and enzyme activities relevant for soil fertility and crop production. Three types of fertilization regimes were tested viz., no fertilizer, conventional as 100% RDF by inorganic fertilizer and combined integrated fertilizer in which 70% RDF with 30% of the nitrogen were supplied by either FYM or pressmud or vermicompost or combination of these two or all. In the experiment, application of 70% recommended dose of fertilizers (RDF) + 30% N supplied through FYM and pressmud improved soil pH, organic carbon, cation exchange capacity, bulk density and water holding capacity of post harvest soil of rice. However, nutrient integrations with organic and inorganic sources had a non significant effect on electrical conductivity, CEC, BD and WHC of soil. Available N, P and K of soil were significantly affected by integrated nutrient treatments which showed up to 25.52, 54.85 and 29.87% increase of these nutrients over control, respectively. The DTPA extractable cationic micronutrients also increase significantly by combined application of organics and inorganic fertilizers. The highest microbial biomass carbon (218.2 μg g-1), urease activity (221.9 μg urea g−1 h−1), alkaline phosphatase (121.5 μg pNP g−1 h−1) and dehydrogenase activity (44.5 μg TPF g−1 d−1) recorded with treatment 70% RDF with 30% N by FYM and pressmud equally. The study reveals the effects of the organic amendments were observed even when they involved a small portion of the total amount of nutrients supplied; thereby confirming that some of the beneficial effects of integrated fertilizer strategies may occur in the short term in rice production and the promising combination was 70% of recommended NPK combined with FYM and pressmud on basis of 30% N by produced the best response.