玉米穗腐病籽粒抗性与穗轴抗性的相互影响

Interaction of the Resistance between Kernel and Cob to Fusarium Ear Rot in Maize

玉米穗腐病是世界上普遍发生、危害严重、防治困难的真菌病害,目前已成为玉米生产上亟待解决的主要问题之一。本研究分别以233份家系组成的RIL群体和452份骨干自交系组成的关联群体为材料,穗轴与籽粒接种拟轮枝镰孢后分别观察其籽粒抗性与穗轴抗性。通过对比穗轴与籽粒接种观察到的籽粒抗性,发现RIL群体中114份家系与关联群体中230份自交系经穗轴接种观察到的籽粒抗性与经籽粒接种观察到的籽粒抗性不一致;而通过对比籽粒与穗轴接种分别观察到的穗轴抗性,发现RIL群体中138份家系与关联群体中247份自交系经籽粒接种观察到的穗轴抗性与经穗轴接种观察到的穗轴抗性不一致。籽粒抗性与穗轴抗性的相互影响可能涉及了新的抗病机制,这为玉米穗腐病复杂的抗性机制的研究提供了新的理论依据。

Maize ear rot is a worldwide serious fungal disease,and at present has become one of the main problems in maize growing areas.However,the measure against this disease remains difficult.In this study,a RIL population comprising 233 lines and a natural population comprising 452 backbone inbred lines were used for evaluating ear rot resistance.The kernel resistance and cob resistance were observed respectively after the cobs and kernels were inoculated with Fusarium verticillioides.By comparing the kernel resistance observed by inoculating cob and kernel resistance observed by inoculating kernel,it was found that the kernel resistance observed by inoculating cobs of 114 lines in RIL population and 230 inbred lines in associated population was not consistent with their kernel resistance observed by inoculating kernel.By comparing cob resistance observed by inoculating kernel with cob resistance observed by inoculating cob,it was found that the cob resistance observed by inoculating kernel of 138 families in RIL population and 247 inbred lines in associated population was not consistent with their cob resistance observed by inoculating cob.Collectively,the interaction between kernel resistance and cob resistance may involve a new disease resistance mechanism,the results provided a new theoretical basis for the study of complex resistance mechanism of maize ear rot.