摘要： 为探讨壳寡糖对菜薹接种立枯丝核菌后的发病率、病情相关蛋白和内源激素含量的影响。以菜心品种油青四九为材料，于菜薹形成初期叶面喷施0.4，2，8 mg/L 壳寡糖预处理2 d，以喷施无菌水为对照，灌根接种立枯丝核菌。结果表明：0.4 mg/L壳寡糖处理可提高菜薹植株对立枯丝核菌的抗性，降低发病率，减少由于病害造成的产量下降。与单独接种立枯丝核菌相比，接种6 d内，0.4 mg/L壳寡糖处理可进一步增强病原菌对菜薹植株叶片中几丁质酶、β-1，3葡聚糖酶的诱导作用；接种6 d后，则显著促进内源激素吲哚乙酸（IAA）和脱落酸（ABA）的形成；接种处理期间，0.4 mg/L壳寡糖处理均显著诱导了乙烯的形成。表明，接种早期，适宜浓度的壳寡糖可提高植株体内病情相关蛋白几丁质酶和β-1，3葡聚糖酶的活性，进而通过较高水平的内源激素乙烯、IAA和ABA的代谢传递抗病信号，从而诱导菜薹植株对立枯病的系统抗性。

关键词: 菜薹, 壳寡糖, 立枯病, 病程相关蛋白, 内源激素

Abstract: The aim of our study was to investigate the influences of chitooligosaccharide on sheath blight occurrence,pathogenesis-related proteins(PRs) and endogenous hormones contents.Youqingsijiu flowering Chinese cabbage(Brassica campestris L.ssp. chinensis var .utilis Tsen et Lee) was chosen as the material.At the early stage of stalk formation,0.4,2 and 8 mg/L chitooligosaccharide and sterile water(control) were sprayed,and 2 days later,plants were inoculated by Rhizoctonia solani.The results showed that 0.4 mg/L chitooligosaccharide could increase the resistance of plants to R.solani,reduce the incidence of sheath blight,and thus reduce the loss of the yield caused with R.solani.Compared with inoculation alone,foliar application of 0.4 mg/L chitooligosaccharide could further enhanced the activities of chitinase and-1,3 glucanase within 6 days of inoculation,and the production of ethylene,indole acetic acid and abscisic acid after 6 days of inoculation.These data suggested that it is important for inducing systematic acquired resistance of flowering Chinese cabbage to sheath blight to induce high level of PRs in a shorter time after inoculation,and later keep high contents of endogenous hormones.

Key words: Flowering Chinese cabbage, Chitooligosaccharide, Sheath blight, Pathogenesis-related proteins, Endogenous hormones

中图分类号: 

• S662.5

• Q945.78

• X53