Effect of organic & inorganic sources of nutrients on soil physical properties, chemical properties and different nutrient status at harvest of the maize crop

The experiment was conducted in plot No. 126 of E block, Main Agricultural Research Station (MARS), University of Agricultural Sciences, Dharwad during kharif, 2011. The geographical co-ordinates of the experimental site are 15026' N latitude and 75007'E longitude and an altitude of 678 m above mean sea level (MSL).The uptake of nutrients by maize increased significantly with incorporation of organic manures with RDF and the highest uptake was recorded in the treatment with PM. Similarly, uptake of nutrients in the treatments with organics and fertilizers each at 50 per cent level with recommended FYM also recorded higher uptake of these nutrients than RDF and the treatments with 100 per cent organics. Water holding capacity, organic carbon, available N, P, K, S and DTPA-extractable Cu, Fe, and Mn in soil improved due to substitution of fertilizer N with organics and the extent of improvement was higher at 100 per cent level . The pH of soil in the treatment receiving only chemical fertilizers was 7.68 which decreased significantly due to substitution of RDN with organics namely FYM, vermicompost and poultry manure at 50 and 100 per cent levels. Maximum water holding capacity of soil varied from 55.0 to 63.7 per cent. Significantly higher water holding capacity of soil was recorded in the treatment with 100 per cent RDN through organics (50% FYM + 50% VC) + recommend FYM (63.7%) and it was on par with other similar treatments with 100 per cent organics along with recommended FYM (T5, T7, and T8).