RD101 (Tung Luang Rangsit), a Non-glutinous Rice Variety

Abstract

Currently foreign consumers put increasing demands on soft textured rice. As medium amylose rice is mostly used for domestic consumption and food processing industry, the production is not sufficient to meet market demand. For the farmers to have a variety with medium amylose content, photoperiod-insensitive, high yield and soft texture of cooked rice for cultivation in irrigated paddy fields at various locations, crossing was made between RD7 and NP847 followed by F₂ to F₁₀ pedigree selection to obtain a promising line PTT11236-37-3-1-2-2-1-1-1. Research had been carried out during 2007 to 2021 through the following crop improvement steps, i.e., observation, yield trials, evaluation on rice disease and insect pests, response to N fertilizer application, analyses for grain physical and chemical quality, milling quality and cooking and eating quality, and farmers’ acceptance evaluation. The promising line was subsequently approved by the Varietal Releasing Committee of the Rice Department to be a certified variety, “RD101” (Tung Luang Rangsit). It is a photoperiod-insensitive, non-glutinous rice with the average yield of 758 kg/rai, 118 days to harvest (transplanting), 110 days to harvest (pre-germinated broadcasting), 117 cm height, erect plant type, green leaf blade, erect leaf and flag leaf attitude, well exserted panicle, 26.6 cm panicle length, mostly compact panicle, heavy secondary branching, 175 healthy seeds per panicle, low panicle shattering, and easy threshability. It has straw-colored husk with a paddy grain size of 10.31 mm length x 2.73 mm width x 2.10 mm thickness, white and slender dehulled grain shape of 7.51 mm length x 2.30 mm width x 1.90 mm thickness and milled rice grain size of 7.34 mm length x 2.23 mm width x 1.85 mm thickness, less chalkiness (0.52), 1,000-grain weight of 28.77 g, paddy weight of 10.79 kg/20 litres, good milling quality with 55.2 percent of whole kernel and head rice, medium amylose content (21.67 percent), low gelatinization temperature, intermediate gel consistency, normal cooked rice elongation, soft and slightly sticky cooked rice, and non-aromatic cooked rice. Remarkable features of RD101 are photoperiod-insensitive and non-glutinous rice, medium amylose content, soft and slightly sticky cooked rice, high yield, high potential yield of 1,070 kg/rai, blast resistance (isolates of the pathogen from Prachin Buri province), and suitable for irrigated paddy fields. Cautions for this variety are susceptible to bacterial leaf blight, brown planthopper and whitebacked planthopper.