烟蚜取食对抗、感烟草品种信号分子和CAT活性的影响

为研究烟草品种抗蚜机制，选用6个不同烟蚜抗性的烟草品种，采用盆栽试验接种蚜虫，研究烟蚜侵袭后第0、3、6、9 h烟草叶片茉莉酸(JA)、一氧化氮(NO)含量以及CAT活性的变化。结果表明，受到蚜虫为害后，叶片JA含量均表现为先增加后降低的趋势，烟蚜取食6 h后叶片JA含量达到峰值，且抗蚜品种JA增量大于感蚜品种。受到蚜虫为害后，抗蚜品种叶片NO含量表现为先增加后减少的趋势，烟蚜取食3 h后NO含量达到峰值，感蚜品种烟蚜取食3 h后的NO含量与取食前差异不显著，但6 h和9 h后显著低于0 h。受到烟蚜侵袭9 h后，参试品种CAT活性均表现为增加趋势，烟蚜取食9 h后，抗蚜品种‘竖把老母鸡2113’的CAT活性增量最多，增幅最大。JA和NO含量以及CAT活性均可以作为烟草品种蚜虫抗性鉴定的生理指标，烟蚜取食5~6 h叶片茉莉酸含量的增幅可以用于鉴定烟草品种抗蚜性。

Response of Signal Molecules and CAT Activities to Aphid in Resistant and Susceptible Tobacco Varieties

To study the mechanism of aphid resistance in tobacco varieties, six tobacco varieties with different aphid resistance were selected and inoculated with aphid in pot experiment. The content change of jasmine acid (JA) and nitric oxide (NO), and CAT activities in tobacco leaves were determined 0, 3, 6 and 9 hours after feeding aphid. The results showed that: after being infested by aphids, the JA content in tobacco leaves increased first, peaked at 6 hours and then decreased. The increment of JA content in resistant varieties was higher than that in susceptible varieties. The NO content in leaves of aphid resistant varieties increased first, peaked at 3 hours and then decreased. The difference of the NO content in leaves of susceptible varieties was not significant between 3 hours’ aphid feeding and 0 h, but decreased significantly after 6 hours and 9 hours. The CAT activity of all tested tobacco varieties showed an increasing trend at 9 h, and CAT activity of aphid resistant variety ‘Shubalaomuji2113’ increased the most. Therefore, JA and NO contents and CAT activity could be used as physiological indicators for aphid resistance identification in tobacco varieties. The increase of JA content in leaves 5-6 hours after inoculation could be used to identify the resistance of tobacco varieties to aphids.