温度对小麦矮腥黑穗病菌冬孢子萌发的影响

温度对小麦矮腥黑穗病菌冬孢子萌发影响的试验结果表明,TCK冬孢子在-2～12℃范围内都可以萌发,5℃为最佳萌发温度。同一分离菌冬孢子在不同温度处理的萌发特性和萌发率有差异;不同分离菌冬孢子在相同温度下的萌发特性和萌发率有很大差异。在5℃下5个分离菌中,冬孢子萌发起始时间最短的为15 d,最长为35 d,培养60 d时分离菌T_t1、T_t2、T_y、T_m和T_u冬孢子的萌发率分别为86.4%、23.9%、23.3%、44.3%和81.0%。根据分离菌T_t2不同温度下培养50 d时的萌发率,建立了萌发率(Y)与温度(X)的模型为Y=0.150 8 exp-0.02949(X-4.957 6)]2,此结果为TCK的风险评估提供了基础数据。

Effects of temperature on germination of teliospore of dwarf bunt(Tilletia controversa Kühn)of wheat

The effects of temperatures on germination of teliospores of Tilletia controversa Kühn were investigated in laboratory.The results showed that teliospores of TCK could germinate at-2～12 ℃,and the optimum temperature for teliospore germination was 5 ℃.Germination characteristics of teliospores of same isolates at different temperatures and different isolates at the same temperature were both great different.The shortest initial germination time among five isolates T_t1,T_t2,T_y,T_m and T_u was 15 days,the longest was 35 days at 5 ℃ after incubation.The germination rates of T_t1,T_t2,T_y,T_m and T_u on day 60 after incubation were 86.4%,23.9%,23.3%,44.3% and 81.0%,respectively.Based on data of teliospore germination of T_t2 on day 50 after incubated,the model of relationship between teliospore germination rates(Y) and temperature(X) for T_t2 was constructed as Y=0.150 77exp(-(0.029 49)(X-4.957 6)².These results of biological experiments will provide fundamental data for risk assessments of establishment of TCK in China.