转截短hpalXoo基因烟草抗病防御酶活性分析

目的]探讨转截短hpalXoo基因烟草中与抗病性有关的5种防御酶系的活性变化.方法]以转截短hpalXoo基因烟草A6-1和对应的非转基因烟草Xanthi叶片为材料,接种烟草花叶病毒（TMV）,测定苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）、过氧化物酶（POD）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的活性.结果]未接TMV时,转截短hpalXoo基因烟草中POD、PPO和CAT酶活性均高于未转基因对照品种,而SOD和PAL活性与未转基因烟草无显著差异.接种TMV后,转截短hpalXoo基因烟草中5种防御酶活性均显著增加,且高于未转基因烟草,并维持在一个较高的水平.结论]截短的hpalXoo基因在烟草中表达能显著提高其抗病防御酶活性水平.

The Defense Enzyme Activity in Transgenic Truncated hpalXoo Gene Tobacco

Objective] The study aimed to explore the 5 kinds of defense enzyme activities in transgenic truncated hpalxoo gene tobacco. Method] The activities of phenylalanine ammonia lyase （PAL）, polyphenol oxidase （PPO）, peroxidase （POD）, superoxide dismutase （SOD） and catalase （CAT） were evaluated on leaf tissue of transgenic truncated hpalao gene tobacco variety A6-1 and the corresponding non- transgenic tobacco variety Xanthi after tobacco mosaic virus （TMV） infection. Result] Under TMV uninoculated condition, the POD, PPO and CAT activities of transgenic truncated hpalxoo gene tobacco werehigher than those of non-transgenic tobacco, while the SOD and PAL ac- tivity difffrences between the two varieties were not significant. After TMV inoculation, all the 5 defense enzyme activities of transgenic trun- cated hpalxao gene tobacco increased significantly, and greater than those of the non-transgenic tobacco, and maintained at a higher level. Conclusion] Transformed tobacco with truncated hpalxao gene can significantly enhance the defense enzyme activities in tobacco leaves.