RD29 (Chainat 80) Rice Variety

Abstract

Farmers in the irrigated area of lower northern Thailand require early maturing variety with resistance to major diseases and insect pests and high quality grain according to market demand so that it can be planted 3 times/year for commercial purposes. Therefore, this research project aimed at developing rice variety to meet the farmers' requirement. The research was conducted in 1989 at Chainat Rice Experiment Station. A variety RD29 (Chainat 80) was derived from 3-way cross of the cross between F1 hybrid of Suphanburi 60 and IR29692-99-3-2-1 and IR11418-19-2-3. Progenies of the crosses had been selected for good performance in intra-station yield trial, inter-station yield trial, farmers' field trial and yield stability evaluation. They were also tested for resistance to major diseases and insect pests, grain physical and chemical qualities, and response to nitrogen fertilizer. The results showed that RD29 is photoperiod insensitive variety. The prominent characteristics of this variety are early maturing of 99 days in dry season and 103 days in rainy season; yield of 876 kg/rai which were 6 and 18% higher than that of Suphanburi 1 and Chainat 1, respectively. RD29 showed good yield stability, moderately resistant to brown planthopper and bacterial leaf blight, non-glutinous long grain rice, less chalkiness and good milling quality. In addition, its brown rice contains 15.7 mg/kg of Fe. It is suitable for growing under irrigated condition in the lower northern region because it can be planted 3 crops/year starting from August, December and April but could not suitable for growing at the mid-September until the end of November because low temperature result in unfilled grain and low yield. RD29 is susceptible to brown planthopper in Nakhon Pathom, Pathum Thani, Ratchaburi, and Chachoengsoa provinces. Therefore, planting this variety in these provinces need more intensive care than other cultivated areas.