小麦品种(系)对纹枯病抗性鉴定及抗病资源的筛选

Resistance evaluation of wheat cultivars (lines) to Rhizoctonia cerealis Varder Hoeven and screening of its resistance resources

室内苗期采用菌落上直播催芽麦粒法和田间连续 2年采用小麦粒砂土壤接菌法对 2 5个小麦品种进行了抗纹枯病性鉴定。结果表明 ,品种间抗感性存在明显差异 ,室内和田间抗感性表现基本一致 ,田间两个年度间抗感性表现具有相对的稳定性。品种南阳 82 5 0 5、S0 48、荆麦 6 6等 7个品种室内病级为 1 0 3～ 1 5 0 ,田间相对抗病性指数为 0 40～ 0 79,两个年度均表现为中抗。 1998～ 2 0 0 0年度共鉴定品种材料 5 48份 ,抗性材料占 17 9% ,其中湖北省94 5 0 36、96 95 1等 11份区预试材料表现为中抗 ,占区预试鉴定材料总数的 2 0 8%。

The resistance of 25 wheat cultivars (lines) to Rhizoctonia cerealis Varder Hoeven were identified by method of sowing germinating wheat seeds inoculated in PDA colony in laboratory, and by test of soil-inoculating wheat grains in fields in 1998-2000, respectively. The results indicated that there were significant differences between their resistances to the sheath blight disease. It showed that results were few differences between the two methods and their resistances in successive two years in field tests were also stable. Seven cultivars of them, such as Nanyang 82505, S048, and Jingmai 66, showed moderate resistance in succesive two years. The diesase index of seedlings in greenhouse were 1.03-1.50, and the relative resistance index in fields were 0.40-0.79. In 1998-2000 about 548 wheat cultivars (lines) from China were identified and screened, and the resistance ratio was 17.9%. Among them, about 11 cultivars from Hubei Province such as 94 5036 and 96 951 showed moderate resistance and the resistance ratio was 20.8% in materials prepared in the regional test.