机械性损伤与氨基丁酸的交互作用对烟草防卫性酶活性的影响

Interaction Effects of BABA and Leaf Wounding on Defense-related Enzymes in Tobacco

摘要:

研究β-氨苯丁酸（BABA）和剪叶对烟草（Nicotiana tabacum L．cv．Yunyan 85）防卫性酶活性和两者间互作对其抗性激发的影响。结果表明：喷施BABA或剪叶都能明显地提高烟草的苯内氨酸解氨酶（PAL）和多酚氧化酶（PPO）的活性，且这些酶活性的变化与BABA的浓度和诱抗时间有关。然而存剪叶后使用BABA，会削弱对PAL和PPO活性的诱导。BABA＋剪叶处理后烟草花叶病（TMV）症状明显较BABA单独处理的严重，这表明BABA和机械性损伤呈现拮抗效应。BABA及其它以水杨酸（SA）为信号分子的化学诱抗剂可能不适宜用于剪叶后的烟草幼苗。

Abstract:

By spraying β-aminobutyric acid （BABA） or/and leaf wounding treatments, the activities of defenserelated enzymes were determined to investigate the interaction effects of BABA and wounding on the resistance of tobacco （Nicotiana tabacum L. cv.Yunyan 85） to tobacco mosaic virus （TMV）. The results showed that wounding or BABA treatment caused a significant increase of phenylalanine ammonia-lyase （PAL） and polyphenol oxidases （PPO） activities, which were associated with BABA concentrations and timing of induction. However, leaf wounded by pruning in combination with addition of BABA decrease the activities of PAL and PPO, resulting in obviously more TMV symptoms than BABA treatment alone. The results suggest that BABA and wounding exhibit antagonistic effect. It is likely that BABA and other SA-dependent chemical inducers should not be applied to the wounded tobacco seedlings.