BIOAVAILABILITY OF SOIL NITROGEN IN LOW WATER-INPUT RICE PRODUCTION

Abstract

The water demand for agriculture, municipal, indus1rial, and environmental purposes will be increasedin the future; less waterwillbe available for rice production. This study was conducted to determine the effects oflow water irrigation on rice yield and nitrogen (N) bioavailability in soil. Five different irrigation treatments, namely, W1 (5 em flooding), W2 (1 em flooding), W3 (first 3 weeks 5 em then 1 em flooding), W4 (first 6 weeks 5 em then 1 em flooding), and W5 (first 9 weeks 5 em then 1 em flooding) were employed with five replications. SPS200 water sampler was used to collect soil extracts and measured N bioavailability in soil. Low water irrigation did not affect rice yield, yield parameters andN content in soil compared to the traditional irrigation system. Our results suggest that rice production can be implemented under low water irrigation condition without affecting rice yield, yield parameters and N content.