Standard Rice Varieties with High Temperature Tolerance at the Ripening Stage in the Warm Region of Japan

Abstract

Fourteen standard rice varieties with high temperature tolerance at the ripening stage in Kyushu region were selected based on apparent by an evaluation of grain quality after ripening under high temperature condition at eight breeding stations, NARO Kyushu Okinawa Agricultural Research Center, Fukuoka Agriculture and Forestry Research Center, Saga Agricultural Research Center, Nagasaki Agricultural and Forestry Technical Development Center, Kumamoto prefectural Agricultural Research Center, Oita Prefectural Agriculture, Forestry and Fisheries Research Center Agricultural Research Division, Miyazaki Agricultural Research institute and Kagoshima Prefectural Institute for Agricultural Development. In the very early and early heading variety groups, four varieties “Natsuhonoka”, “Mineharuka”, “Nipponbare” and “Koganebare” were selected as having strong, moderately strong, middle and moderately weak tolerance to high temperature, respectively. Two varieties, “Hatsuboshi” and “Matsuribare”, had weak tolerance. In the medium heading variety group, five varieties, “Otentosodachi”, “Koganemasari”, “Nikomaru”, “Shinrei” and “Hinohikari”, were selected as strong, moderately strong, middle, moderately weak and weak tolerance to high temperature, respectively. In the late and very late heading variety group, three varieties, “Nishihikari”, “Tachiharuka” and “Akisayaka”, were selected as moderately strong, moderately weak and weak tolerance to high temperature, respectively. High temperature tolerance of newly developed cultivars and lines in Kyushu region would be evaluated by observing grain quality after high temperature treatment at the ripening stage in comparison with standard varieties selected in this study.