02615nam a2200181Ia 4500 26492 26492 OSt 20220826172909.0 140128s9999 xx 000 0 und d 630 DIV/IM Divya ULK Improving Nutrient Use Efficiency In Rice Through Coating Of Ferilizers Vellanikkara Department of Agronomy, College of Horticulture 1999 MSc A study was conducted during 1998-99 to investigate the effectiveness of coating of diammonium phosphate and urea with different materials on the growth, yield and nutrient use efficiencyin rice, which included an incubation study and a field experiment. The field experiment consisted of 15 treatment combinations involving varying levels (100% and 75% of recommended dose) ofN and P supplied through uncoated or coated (with neem extract or neem extract-resin mixture) diammonium phosphate and urea. The incubation study included an additional treatment of absolute control. The results of the incubation study showed that the ammoniacal N, . nitrate N and available P content in soil progressively increased up to 30 days of incubation in the case of treatments receiving coated fertilizers, while the treatments receiving uncoated fertilizser showed an increase only up to 10-15 days. The effect of the treatments on yield and yield attributes was found to be non-significant, except for the number of panicles m-2. However marginal.increase in grain yield was observed in general in treatments receiving coated DAP. With regard to nutrient uptake, the effect of treatments was significant at all the three stages (active tillering, panicle initiation and harvest) in the case ofN, at panicle initiation in the case ofP and at active tillering and panicle initiation stage in the case of K. In general, coating was found to have positive influence on the uptake ofN, P and K. The positive influence of coating on the availability of N and P and its uptake by the crop failed to reflect on grain yield. The increased uptake of Fe and Mn by rice in the laterite soils may be the likely reason for the absence of response to the treatments. The overall result show that from the point of view of efficiency, coating has a definite advantage and this advantage can be tapped in terms of production only after eliminating the basic factors responsible for yield inhibition of rice grown in laterite soils'. Jose Mathew (Guide) http://krishikosh.egranth.ac.in/handle/1/5810103661 ddc TH 0 0 ddc 0 0 KAUCLV KAUCLV THESES 2014-03-18 0 630 DIV/IM 171549 2014-03-18 00:00:00 2014-03-18 TH