SANKARA RAO, VDIVYA, P2016-06-212016-06-212012http://krishikosh.egranth.ac.in/handle/1/67616A field experiment entitled “Effect of organic sources on soil properties and yield of rice (Oryza sativa L.)” was conducted at Agricultural College Farm, Bapatla on a sandy loam soil during Rabi, 2010-11. The experiment consisted of seven treatments viz., T1 -100% RDN through urea, T2 - 100% RDN as FYM, T3 - 125% RDN as FYM, T4- 150% RDN as FYM, T5 -100% RDN as vermicompost, T6 - 125% RDN as vermicompost and T7 - 150% RDN as vermicompost which was laid out in a Randomized Block Design with three replications. The results revealed that the growth parameters such as plant height, number of tillers, productive tillers and yield attributes viz., drymatter production, panicle length and 1000 seed weight were highest with the application of 100% recommended doses of mineral nitrogen and comparable with 150% application of N in the form of organics. Grain and straw yields followed the same trend as that of growth parameters and at higher levels of nitrogen in the organic form, vermicompost performed better than FYM. More content and uptake of nitrogen was observed with the application of nitrogen in mineral form while the phosphorus, potassium, micronutrients content and uptake of paddy was high with the addition of FYM and vermicompost. Dehydrogenase activity of soils collected at two stages of rice crop i.e., panicle initiation and at harvest was high in the treatments receiving organics. Quality parameters viz., volume expansion ratio and amylose content of rice was high when organics were used. Higher values were recorded with application of vermicompost than FYM Improvement in physico-chemical properties like organic carbon, bulk density, porosity, available macro and micro nutrients was observed with the application of organics. At added levels of nitrogen in organic form vermicompost performed better than FYM. From the present investigation, it can be concluded that under sandy loam soils of Bapatla, nitrogen applied in the form of organics improved physical conditions, availability of macro and micro nutrients and at higher levels produced the yields comparable with the recommended dose of nitrogen in mineral form.envermicomposting, farmyard manure, rice, fertilizers, yields, organic fertilizers, grain, nitrogen, nutrients, cropsThesis