马铃薯疮痂病最适诱抗剂筛选试验

Selection of the optimal inducers for potato scab

【目的】研究植物病害诱抗剂对马铃薯疮痂病的诱抗效应,以期为马铃薯疮痂病防治提供一种新的途径。【方法】选用康壮素、烯丙苯噻唑(PBZ)、有效霉素A(VMA)、苯丙噻重氮(BTH)和水杨酸(SA)5种植物病害诱抗剂对马铃薯疮痂病进行诱抗试验,通过测定发病率、发病指数和相对防效确定马铃薯疮痂病的最适诱抗剂及最佳使用浓度,并在最佳使用浓度下测定马铃薯叶片的生理指标和相关酶活性。【结果】5种植物病害诱抗剂中康壮素和PBZ对马铃薯的诱抗效果不明显,其余3种诱抗剂对马铃薯疮痂病均具有一定的诱抗效果,发病率与发病指数均显著下降,其中以SA的诱抗效果最佳。最佳使用浓度筛选试验结果表明,SA在浓度为1.00mmol/L时对马铃薯疮痂病的相对防效最高,达67.6%;在此浓度下马铃薯叶片超氧阴离子自由基含量和丙二醛含量降低,色素、可溶性蛋白、相关酶系活力指标均显著增加。【结论】SA为马铃薯疮痂病的最适诱抗剂。规模化生产中可在马铃薯结薯期叶面喷洒浓度为1.00mmol/L的SA,间隔7d/次,至马铃薯成熟期停止喷洒,可提高马铃薯对疮痂病的抗性。

[Objective]In order to provide a new way for preventing potato scab, this study was performed to analyze the effect of plant disease inducers on resistance induction against potato scab. [MethodlFive kinds of plant disease inducers, HarpinEa, PBZ, VMA, BTH and SA, were used to screen out the optimal inducer and best inducer concentration based on in- fection rate, infection index and relative efficiency. The related physiological and enzyme activity indexes were determined at the best inducer concentration. [Result]The resistance effects of HarpinEa and PBZ inducers were not obvious. VMA, BTH and SA inducers had different effect of induced resistance on potato scab, and infection rate and infection index were dramati- cally declined. SA was the optimal inducer. The best inducer concentration was 1.00 mmol＇L-I and the relative control effect to the scab was 67.6% under this concentration. The indexes of SAFR and MDA descended, but the indexes of pigment, soluble protein and related enzymes activity were obviously higher than those of the control. [ Conclusion ]SA, as the optima/inducer for potato scab, will reduce the incidence of potato scab and improve the quality of potato when using 1.00 mmol/L SA to spray foliar during potato growing every seven days.