2,3-丁二醇对草地早熟禾褐斑病诱抗作用及抗病互作中寄主木质素的变化

2,3-butanediol induced resistance to brown patch and changes in host lignification during resistance interactions in Poa pratensis

摘要:

【目的】 探究外源诱导剂2，3‐丁二醇（2，3‐butanediol，2，3‐BD）是否能提高草地早熟禾对褐斑病菌（Rhizoctonia solani）的抗性。【方法】 采用不同浓度2，3‐BD对草地早熟禾进行诱导处理，通过人工接种的方法研究2，3‐BD对早熟禾褐斑病的诱导抗性并进行病情评价，测定草地早熟禾木质素含量和木质素合成酶的活性。【结果】 2，3‐BD诱导显著降低草地早熟禾植株发病率，其中300 μmol/L浓度诱导下抗病效果最佳，早熟禾褐斑病发病率由90%降低到50%，诱导效果可达到74%，显著增强了植株对褐斑病的抗性（P＜0.05）。2，3‐BD对R. solani生长没有明显影响。2，3‐BD诱导提高了草地早熟禾木质素合成酶PAL、4CL、POD、LAC的活性和木质素的生物合成（P＜0.05），300 μmol/L浓度处理木质素含量最大。【结论】 2，3‐BD能显著提高草地早熟禾对褐斑病的抗性。

Abstract:

【Objective】 This study aims to investigate whether the exogenous inducer 2，3‐butanediol can en hance the resistance of Poa pratensis to brown patch.【Method】 Used different concentrations of gradient inducer 2，3 BD to induce Poa pratensis，and studied its resistance to brown patch and disease evaluationby artificial inoculation. On this basis，lignin content and lignin synthase activity were determined.【Result】 The results showed that 2，3‐BD induction significantly reduced the incidence rate of Poa pratensis，and 300 μmol/L concentration induced the best dis ease resistance effect，which could reduce the incidence rate of Poa pratensis brown patch from 90% to 50%，and the induction effect could reach 74%，significantly enhancing the resistance of plants to brown patch （P＜0. 05）. It was found that 2，3‐BD did no significant effect on the growth of Rhizoctonia solani. The induction of 2，3‐BD enhanced the activities of PAL，4CL，POD and LAC lignin synthases and the biosynthesis of lignin in bluegrass （P＜0. 05）， and the lignin content was the highest when treated at a concentration of 300 μmol/L.【Conclusion】 2，3‐BD can sig nificantly improve the resistance of Poa pratensis to brown patch.