02531nam a2200157Ia 4500003000400000005001700004008004100021082001600062100001400078245007600092260007400168502000800242520204300250700002402293856005602317OSt20220826172909.0140128s9999    xx            000 0 und d  a630bDIV/IM  aDivya ULK  aImproving Nutrient Use Efficiency In Rice Through Coating Of Ferilizers  aVellanikkarabDepartment of Agronomy, College of Horticulture  c1999  bMSc3 aA 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'. 

  aJose Mathew (Guide)  uhttp://krishikosh.egranth.ac.in/handle/1/5810103661