【摘要】 分析了几种化学制剂对干热风环境下葡萄叶片气体交换及叶绿素荧光参数的影响,以探求田间葡萄应对干热风胁迫的保护措施。以田间生长5年生‘威代尔’葡萄为试材,在干热风来临前预喷一定浓度的芸苔素内酯、S-诱抗素以及黄腐酸钾,对照喷等量清水,干热风来临当天测定叶片气体交换参数日变化,结合快速叶绿素荧光诱导动力学及叶绿素荧光淬灭分析,探讨几种化学制剂对田间葡萄光合作用抵御干热风的影响。结果表明,干热风环境导致了田间葡萄叶片净光合速率(Pn)的明显降低,伴随叶片光系统Ⅱ(PSⅡ)最大光化学效率(Fv/Fm)的降低及非光化学淬灭(NPQ)的升高,表征PSI光抑制的指标[Y(NA)]未发生明显变化,表明干热风导致了葡萄叶片PSⅡ光抑制的发生,但未显著影响PSI活性。喷施几种化学制剂均不同程度缓解了干热风环境对葡萄叶片光合作用的胁迫作用,其中S-诱抗素和芸苔素内酯作用比较明显,叶面喷施维持了较高的PSⅡ活性,光化学淬灭系数(q P)及实际光化学效率(Fv′/Fm′)降低幅度较小,黄腐酸钾在葡萄上的效果低于S-诱抗素和芸苔素内酯,表明喷施S-诱抗素和芸苔素内酯可以有效缓解田间干热风胁迫下葡萄叶片PSⅡ光抑制程度,从而维持较高光合活性。更多还原

【Abstract】 In order to investigate the protective measure for dealing with the dry-hot wind in the field, effects of different chemical treatments on the dry-hot wind tolerance of photosynthesis in grape leaves were analyzed. According to the weather report, brassinolide, abscisic acid and fulvic acid potassium were sprayed on ‘Vidal Blanc’ grape leaves, using the water as the control. By simultaneously analyzing the gas exchange parameters and chlorophyll a fluorescence transient as well as analyzing chlorophyll quenching, the effects of different chemical treatments on the dry-hot wind tolerance of photosynthesis in grape leaves were studied. The results showed that the dry-hot wind decreased the net photosynthetic rates(Pn) of grape leaves, accompanied with the decrease of the photosystem Ⅱ(PSⅡ) maximal photochemical efficiency(Fv/Fm) and the increase of non-photochemical quenching(NPQ), however, the PSI quantum yields of non-photochemical [Y(NA)] had no significant change, indicating that the dry heat wind resulted in PSⅡ photoinhibition, but PSI activity remained stable. Different chemical treatments alleviated the inhibition of the dry-hot wind on the photosynthesis in grape leaves on different degrees, among which, abscisic acid and brassinolide treatments showed more obvious effects, which maintained the PSⅡ activity, the photochemical quenching coefficient(qP) and actual photochemical efficiency(Fv′/Fm′) decreased less. The alleviated effects of fulvic acid potassium were less than that of abscisic acid and brassinolide. The results reminded that abscisic acid and brassinolide sprayed on grape leaves alleviated the PSⅡ photoinhibition, which maintained the photosynthesis activity under the dry-hot wind.更多还原