Extrapolation of nitrogen management technology for direct-seeded rice in Ubon Ratchathani province using geographic information system as a tool

• Published in: Thai Agricultural Research Journal (Thailand)
• Main Authors: Grisana Linwattana(Department of Agriculture, Bangkok (Thailand). Horticulture Research Institute. Nan Horticulture Research Station), Singh, Virendra Pal(International Rice Research Institute (Philipines)), Lales, Joveno S.(University of the Philippines, Los Banos (Philippines). College of Agriculture)
• Format: Journal Article
• Language: Thai
• Published: 01.09.2002
• Subjects: Broadcasting; Direct sowing; Geographical information systems; Land suitability; Nitrogen fertilizers; Oryza sativa; Thailand
• ISSN: 0125-8389

Geographic information System (GIS) was used as a tool to evaluate land suitability in Ubon Ratchathani province for direct-seeded rice and N management technology extrapolation during 1998-2000. Six factors namely annual rainfall, soil texture, cation exchangeable capacity, climatic drought occurrence, farmers practices and maximum depth of inundation were attributed. The results showed that there were three categories of land suitability in Ubon Ratchathani province as moderately suitable (S2), marginally suitable (S3), and not suitable (N) category. The marginally suitable areas with limitation like flooding (S3f) were included in the S3 category. Nitrogen management for direct seeded rice a new technology generated in the Ubon Ratchathani Rice Research Center that is 9.6 kg N/rai applied in three splits, smaller quantity of N, e.g. 1 in 4 of the total amount applied at 15 and 30 days after emergence (DAE), the remaining half applied at 45 DAE were validated and compared with farmers practices through on-farm trials. The extrapolation and recommendation were also made on the qualities of land suitability classification basis. On-farm trials consistently gave higher grain yield as a result of the new N management technology application as compared to farmers practices in S2 and S3 category. Comparable grain yield of the two N applications was obtained form N category, indicating differences in environmental factors in the domains.