小麦条锈病菌非亲和性小种诱发小麦抗锈性研究

 在水源11、洛夫林10等7个品种上分别选择小麦条锈菌CY17、CY28等9个生理小种中非亲和小种进行诱发接种,亲和小种为挑战小种。观察发病后的病情指数并与单独接种诱发小种和单独接种挑战小种处理的病情指数进行比较。证明诱发抗病现象是比较普遍的,但表现程度因小麦品种、诱发小种和挑战小种而不同。诱发抗病性的表达时间可持续8 d,以诱发接种后1~2 d表达最强。诱发接种量与诱发抗病性表达呈指数函数关系,也间接证明这种诱发抗性是局部的。作者认为:诱发抗病性在品种、诱发和挑战小种不同组合之间的差异在小种动态中会起一定的作用。

Resistance to wheat stripe rust induced by avirulent race of Puccinia striiformis

Seven wheat varieties were used in inoculation with nine physiological races of Puccinia striiformis to study varietal resistance to the compatible races after induction by incompatible races. The results from greenhouse experiments showed that the induced resistance did exist in many variety race combinations. However, the degree of induced resistance varied with the combinations. The induced susceptibility also existed in several combinations. The effect of induced resistance lasted for 8 days,but was strongest 1-2 days after inoculation.The time interval between inducing inoculation and challenging inoculation had important effect on the expression of induced resistance. The induced resistance was most remarkable when the time interval was 24 h. When the time interval was 48 h, the induced resistance became comparatively week. The amount of inoculums quantitatively affected the induced resistance. An exponential relationship between concentration of spore suspension (X) and the induced effect (Y) were obtained. The induced resistance may play a certain role in the disease epidemics in certain combinations of variety and race.