Th e loss of major nutrients can be high in rice (Oryza sativa L.) fi elds, particularly rainfed rice, where water fl owing from fi eld to fi eld during periods of high rainfall not only reduces the nutrient use effi ciencies but also has the potential for environmental degradation. We examined the infl uence of deep point placement of N, P, and K briquettes compared to broadcast incorporation of N, P, and K on fl oodwater nutrient loads aft er fertilizer application and on the performance of wet season rice in a Vertisol. Broadcast application of N as urea resulted in an average 10 times higher amounts of ammonium N in fl oodwater compared to deep placement of urea briquette. Th e broadcast application of single superphosphate resulted in 67 times higher amounts of P in fl oodwater than plots receiving deep placed P. Th e fl oodwater NH 4 + -N and P content in the deep placement treatments were negligible-similar to fl oodwater N and P content without fertilizer application. Th e fl oodwater K amounts were also significantly lower with deep placed N-P-K briquettes. Signifi cantly higher grain and straw yields, total N, P, and K uptake, and N and P use effi ciencies were observed with deep placement of N-P-K compared to broadcast application of N-P-K. Deep placed N-P briquettes gave signifi cantly higher grain yield, straw biomass, total P and K uptake, apparent P recovery, and agronomic N and P use effi ciencies when plant spacing was reduced from 20 by 20 cm to 20 by 10 cm. Closer plant spacing led to better utilization of P and K and provided opportunities for deep placement of N-P or N-P-K briquettes in soils with low available P. Combining site specifi c characteristics (high soil pH, low percolation rate, high rainfall and surface runoff s) with plant spacing and N-P-K briquettes prepared based on site-specifi c nutrient requirements off ers potential for higher yields, improved fertilizer use effi ciency, balanced fertilization, and reduced nutrient losses.

Metarhizium isolates from soil (53) and insect hosts (10) were evaluated for extracellular production of cuticle degrading enzyme (CDE) activities such as chitinase, chitin deacetylase (CDA), chitosanase, protease and lipase. Regression analysis demonstrated the relation of CDE activities with Helicoverpa armigera mortality. On basis of this relation, ten isolates were selected for further evaluation. Subsequently, based on LT 50 of the 10 isolates towards H. armigera, five isolates were selected. Out of these five isolates, three were selected on the basis of higher conidia production (60Á75 g/kg rice), faster sedimentation time (ST 50 ) (2.3Á2.65 h in 0.1% (w/v) Tween 80) and lower LC 50 (1.4Á 5.7 )10 3 conidia/mL) against H. armigera. Finally, three Metarhizium isolates were selected for the molecular fingerprinting using ITS sequencing and RAPD patterning. All three isolates, M34412, M34311 and M81123, showed comparable RAPD patterns with a 935G primer. These were further evaluated for their field performance against H. armigera in a chickpea crop. The percent efficacies with the three Metarhizium isolates were from 65 to 72%, which was comparable to the chemical insecticide, endosulfan (74%).

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