RD35 (Rangsit 80) Rice Variety

Abstract

Low productivity of rice in rainfed area of central region is due to the use of local varieties with low yield potential associated with other factors such as rainfall variation, diseases and insect pests, topography, soil fertility and soil acidity in some area. To overcome these problems, photoperiod-sensitive non-glutinous rice varietal improvement program was conducted in 1979 at Pathum Thani Rice Research Center in order to obtain high yielding variety, erect and strong culm, rather short cultivar, high quality grain which is suitable for cultivation in rainfed area of central region. The development of three-line hybrids for rainfed area was carried out by crossing F₁ generation of IR5201-65-1-2 with (early Pinkaew 27 x Jao Luaeng 11). Then grow out F₁. generation and F₂, bulk testing with F₃,-F₆ pedigree selection to determine its performance. Finally, RSTLR7909-43-1-1-5 hybrid line was obtained. It has been officially released and registered as certified variety, called "RD35" by Rice Department 's Variety Approval and Released Committee. Varietal potential was evaluated under intra-station yield trial, inter-station yield trial and farmer's field, including productivity grown under soil acidity, important diseases and insect resistances, nitrogen responsibility, physical and chemical properties, milling quality, cooking and eating qualities. This project had been carried out during 1979-2002, total 23 years. It can be concluded that RD35 is photoperiod-sensitive non-glutinous rice, rather short cultivar with 132 cm height, erect and strong culm, straight leaves, harvesting date is about the end of November-early December, average yield is 650 kg/rai. The productivity is quite high when grown under acid soil (600 kg/rai), good milling quality with 100% white grain. This variety is similar to "Saohai". It is rather tolerant to bacterial leaf blight and whitebacked planthopper. RD35 is suitable for planting in rainfed area of central region, particularly in acid soil. But care should be taken since it is susceptible to the brown planthopper.