Water management

Rice (Orysa sativa L) is cultivated either as a rain fed or as a supplementary or fully irrigated crop. The system of rice cultivation mainly depends on the available rainfall and its distribution. In general, except in semi arid areas where rice cultivation is marginal, average rainfall in rice growing areas of Sri Lanka can meet at least part of the water requirement for a rice crop during it cropping season. Thus in strict terms there is no fully irrigated rice cultivation in Sri Lanka. Rice is a semi aquatic plant and does not need standing water for a successful rice crop. However, uncertainty of water supply, either through irrigation or rain, and to reduce weed infestation rice is always cultivated as a crop with standing water. Response of the rice plant to water stress is varied with its growth stage and other agronomic practices. Direct sown rice crop is less prone to drought than a transplanted crop. Highest water use is during the preparation of land, thus land preparation with minimum timing and maximum use of rain water at the correct time of the season is recommended.