我国南方稻区水稻骨干亲本纹枯病抗性鉴定与分析

Identification and analysis of core rice parents' resistance to rice sheath blight in south rice production regions of China

运用改进的纹枯病菌接种法,对当前我国南方稻区17个骨干亲本纹枯病抗性进行了田间鉴定,测定和分析了各材料的纹枯病病级(RD)、相对病斑高度(HR)及株高(HP)。通过试验,将17个骨干亲本分为抗病、中等抗病、中等感病和感病4种类型;筛选出了3个抗病亲本(明恢63、蜀恢527、广恢128)和3个中抗亲本(绵恢725、珍汕97B和协青早B);供试亲本的平均RD为4.78,平均HR为0.52;通过分析,发现纹枯病病级(RD)和相对病斑高度(HR)呈极显著正相关(y=8.373x+0.435,y=RD;x=HR)、株高和病级相关不显著。

The resistance of core rice parents to rice sheath blight in south rice production regions of China was identified in fields by an improved method of inoculation, which was carried out with short match bars incubated with AG1-IA. The indices RD, HR and HP were measured and analyzed in the experiments. Seventeen core parents were classified into 4 types： resistance, moderate resistance, moderate susceptibility and susceptibility. Three resistance parents （Minghui63, Guanghui128 and Shuhui527） and 3 moderate resistance parents （Mianhui725, Zhenshan97B and XieqingzaoB） were screened from 17 core parents in this study. The average resistance level to rice sheath blight and average HR of all core parents were 4.78 and 0.52, respectively. There was very significantly positive correla tion between RD and HR（y=8. 3733x＋0. 435,y=RD,x=HR）, but RD was not quite correlated with He in this experiment, which suggested that HR could be used as one of the supplementary indices for resistance evaluation of rice sheath blight.