甘蔗黑穗病菌胁迫对甘蔗内源激素含量的影响

【目的】研究接种黑穗病菌后甘蔗内源激素含量的变化，为揭示甘蔗对黑穗病的抗性机制及抗性育种提供理论依据。【方法】以甘蔗品种GT28和ROC22为材料，设接种黑穗病菌处理，以接种无菌水为对照，研究不同抗性甘蔗品种幼苗叶片内源激素含量的变化。【结果】受黑穗病菌侵染后，甘蔗幼苗叶片内源激素IAA和GA含量降低，ABA、SA和JA含量提高，IAA/ABA值下降且低于对照。与感病品种ROC22相比，抗病品种GT28有较低的IAA、ABA含量和较高的GA、SA含量，IAA/ABA值变化幅度较小，而抗感品种间内源JA含量无明显差异。【结论】受黑穗病菌侵染后，甘蔗幼苗叶片IAA、GA、ABA、SA含量及IAA/ABA值变化与不同甘蔗品种的抗性密切相关，可作为甘蔗对黑穗病抗性的生理指标。

Changes of endogenous hormone content in sugarcane under smut pathogen stress

【Objective】The present study was conducted to study the changes of endogenous hormone contents in two sugarcane varieties with different disease resistance after smut infection in order to provide references for illustrating the mechanism of sugarcane smut resistance and breeding smut resistant sugarcane varieties. 【Method】In the experiment， changes of endogenous hormone content in sugarcane varieties GT28 and ROC22 were studied after the smut spore inoculation with sterilized water inoculation were used as control. 【Result】After inoculation with smut pathogen， the contents of endogenous hormones in the seedling leaves changed. The IAA and GA contents decreased， while the ABA， SA， and JA contents increased， and the IAA/ABA ratio decreased after smut infection compared to that of the controls. Compared with the susceptible variety ROC22， the IAA and ABA contents were lower and the GA and SA contents were higher in the resistant variety GT28； the IAA/ABA ratio decreased relatively more in ROC22 than in GT28， and the JA content had no significant differences between the two sugarcane varieties. 【Conclusion】The changes of IAA， GA， ABA， and SA contents and the IAA/ABA ratio in the seedling leaves were closely related to the smut resistance of different sugarcane varieties， therefore they could be used as indexes for sugarcane smut resistance.