Improvement of Local Rice Productivity in the Thai Highland Areas

Abstract

Rice is the most important staple food crop for hill tribe farmers in the Thai highland areas. Low yields result in insufficient production to meet household consumption needs. The research objectives of this project are: (1) to use pure-line selection methods to improve local rice yields, (2) to study methods to reduce water needs for paddy field production. The research was conducted in paddy fields with the cooperation of hill tribe farmers. The experiment used two seedling aged, 15- and 30-days-old and two soil moisture conditions, flooded and non-flooded. Single rice seedlings were transplanted and then rogued to remove off types, at four stages; tillering, booting, flowering, and pre-harvesting. Results showed that Li-ka, a local cultivar grown at 600 above mean sea level (MSL), produced 445 kg/1,600 m2 in flooded soil and 454 kg/1,600 m2 in non-flooded soil conditions. Bua-bor-bae, a local cultivar planted above 1,000 MSL, produced 540 kg/ 1,600 m2 under non-flooded soil conditions and 480 kg/1,600 m2 in flooded soils. The 12.5% yield reduction of Bua-bor-bae in flooded soil was the result of bacterial leaf blight disease, which was more severe in flooded than non-flooded soil. Yields did not differ between the two different seedling ages. The experiment shows that the local rice cultivars Li-ka and Bua-bor-bae can be grown in non-flooded soils with yields equal to or greater that those in flooded soils. Cultivation under non-flooded soil conditions can help to conserve water resources, because non-flooded cultivation consumes 40% less water than flooded soil cultivation. Action research and participatory demonstration projects with cultivation under flooded soils should be undertaken to build trust and confidence among farmers so they are willing to adopt non-flooded soil rice cultivation technologies.