RESEARCH OF WATER-SAVING AND HERBICIDE-FREE IRRIGATION TECHNOLOGY FOR RICE CROP UNDER WATER DEFICIT CONDITIONS IN KYZYLORDA REGION

Abstract

Kyzylorda region is the main producer of rice in Kazakhstan. Annually, out of 195 thousand hectares of irrigated fields used in the region, about 80-90 thousand hectares are sown with rice. However, every year due to low water in the lower reaches of the Syr Darya River there are problems with water supply for water-loving rice crop. Prospects of rice production under conditions of water deficit in Kyzylorda region are conditioned by necessity of application of water-saving technologies providing favorable thermal, salt and nutrient regimes. Water consumption of rice culture is 9,0-11,0 thousand m3/ha depending on biological specificity of rice and this indicator is 3-4 times lower than irrigation norm of rice in the region. Most of the water excessively applied to rice fields is wasted in summer and increases secondary soil salinization and reduces crop yields. Besides, due to deterioration of technical condition of irrigation canals and collector-drainage systems, mineralized groundwater is located close to the ground surface. Undoubtedly, this will increase soil re-salinization and reduce crop yields. One of the most difficult problems in rice fields is weed control. Application of chemical deteriorates the ecological condition of the region and reduces its economic efficiency. As a result of research on the development of water-saving and herbicide-free technology of rice irrigation under conditions of water shortage in the Kyzylorda region was saved 6460-9070m3 of water per hectare, ie compared to the current irrigation regime was saved 25-30% of water, and rice yield increased by 6.0-8.0 centners per hectare. In addition, an effective method of weed control in rice fields is the destruction of weeds by water regime without the use of pesticides and the improvement of irrigation technology of rice crop. As a result of the research it was found that maintenance of 20 cm water layer in checks after full germination of rice seeds provides 84% weed suppression and high yield of rice without herbicides