RD12 (Nong Khai 80) Rice Variety

Abstract

Most of rice growing area in northeastern and upper north of Thailand normally is rainfed rice. Farmers prefer to grow RD6 rice variety with good cooking quality but it is susceptible to blast disease when growing in upland. Therefore, farmers have to grow Hahng Yi 71 variety which is resistant to blast but poor cooking quality. The solution to this problem is to develop new improved variety which is suitable for growing in this area (upland); early harvesting variety and resistant to blast. The breeding program was conducted at Sakon Nakhon Rice Research Center in 1992. The program had been initiated by crossing between Hahng Yi 71 and RD6. The hybrid lines were selected until F₅ at Khon Kaen Rice Research Center and obtained improved line UBN92110 - NKI-B-B-B-30 - KKN -1, which has been proved from breeding committee of Rice Department, and named "RD12 (Nong Khai 80)". Hybrid vigor tests were undertaken both inter - station yield trial and on-farm yield trial including yield stability, resistant to important disease and insect pests, nitrogen response, seed quality, physico-chemical properties, cooking quality, and farmers' acceptance during 1992 - 2003 (11 years). It was found that RD12 is glutinous rice, photoperiod-sensitive, flowering date during 5 - 25 October, height 108 - 138 cm and yield 428 -538 kg/rai. The prominent of this variety is early maturity, its maturity date is about 10 days earlier than RD6, strong culms, hard lodging, good cooking quality, rather resistant to blast in many growing area, and farmers accepted. It is recommended to grow in rainfed area in northeastern part particularly in the short rainy season or upland area. Since this variety is susceptible to bacterial leaf blight and brown planthopper therefore, care must be taken to protect rice crop from damaging of these disease and insect pest.