BTH诱导花椰菜对菌核病的抗性研究

 利用苯并噻二唑BTH处理菌核病抗性不同的花椰菜品种幼苗, 采用营养生长期活体叶片菌丝块接种鉴定法评价菌核病抗性诱导效果，结果表明经BTH处理的植株菌核病病情指数明显下降, 对感病品种和抗病品种的诱抗效果分别达到81.5%和63.8%。对于花椰菜重要的防御酶活性变化研究结果表明，BTH诱导处理的花椰菜植株过氧化物酶（POD）、抗坏血酸酶( SOD )、过氧化氢酶（CAT）、苯丙氨酸解氨酶（PAL）和多酚氧化酶( PPO)的活性均有所提高。同时病程相关蛋白几丁质酶和β-1,3-葡聚糖酶的活性也增加。 利用半定量RT-PCR方法检测防御反应基因表达，结果表明BTH诱导首先激发了植株 PR-1等基因参与的水杨酸信号传导防御反应途径的发生，同时PDF1.2 基因的上调表达说明BTH诱导也影响了茉莉酸信号传导途径。

Studies on BTH-induced resistance to Sclerotinia sclerotiorum in cauliflower and physiology basis

The effects of benzothiadiazole(BTH) spraying on cauliflower resistance to Sclerotinia sclerotiorum were evaluated.The disease indices were investigated in susceptible and resistant varieties inoculated with mycelium agar disks to seedling leaves.The results showed that BTH significantly reduced the size of rot tissue compared with controls,and the control efficacies of BTH treatment were 81.5% and 63.8% in susceptible-and resistant-varieties respectively.The activities of defensive enzymes such as POD,SOD,CAT,PAL,and PPO were increased in BTH-treated seedlings after inoculation with S.sclerotiorum.The activities of chitinase and β-1,3-glucanase in cauliflower also increased in BTH-treated seedlings.The expression patterns of two marker genes in defense signaling pathways and four pathogenesis-related protein genes were detected using semi-quantified RT-PCR.The results indicated that BTH-induced resistance to S.sclerotiorum in cauliflower mainly through SA-dependent signaling pathway,and the up-regulated expression of PDF1.2 showed JA/ET signaling pathway may also influenced by BTH-induced resistance in cauliflower.