【Objective】Two hundreds and twenty five new rice lines, bred using blast resistant parents, viz., Kangwensimiao, Xinyinzhan and BE 621, have been evaluated for panicle blast resistance which was a bais for registration of new rice varieties. 【Method】 Rice blast was inoculated on 225 new rice lines under natural field conditions in Limu County, Cenxi, Guangxi(China), and the crop was investigated for the level of tolerance. The resistant parents Kangwensimiao, Xinyinzhan and BE621 were taken as resistant control, and Youzhan 8 as susceptible control variety. 【Result】 The tested 225 new rice lines differed greatly in level of resistance to panicle blast disease. Out of 225 lines, 13 lines(5.8%) showed grade 1 resistance (highly resistant), 118 lines (52.4%) showed grade 3 resistance (moderately resistant), 65 lines (28.9%) showed grade 5 resistance (moderately susceptible), 14 lines (6.2%) showed grade 7 resistance (susceptible) and 15 lines (6.7%) showed grade 9 (high susceptible). On comparing the offsprings with their resistant parents, it was found that grade 1-3 resistance was observed only in 59.6, 59.3 and 51.4% offspring of Kangwensimiao, Xinyinzhan and BE621, respectively. 【Conclusion】 The offsprings of Kangwensimiao and Xinyinzhan were found highly resistant to rice blast compared to those of BE621. The high and moderately resistant lines identified in this study can be used in breeding programs for breeding rice blast resistant varieties.
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