---

作 者 ：胡文海1*；詹秀花2；闫小红1；王旭明1；黄黎锋3

期 刊 ：植物研究 2015年 35卷 6期 页码：908-914

关键词：辣椒；干旱；24-表油菜素内酯；抗氧化酶系统；转录因子；

Keywords:pepper(Capsicum annuum L.), drought stress, 24-epibrassinolide, antioxidant system, transcription factors,

摘 要 ：报道了干旱胁迫下外源24-表油菜素内酯（EBR）对辣椒幼苗叶片H₂O₂和MDA含量，抗氧化酶活性，以及耐旱相关基因表达的影响。结果表明，0.1 μmol·L^-1 EBR处理诱导了辣椒幼苗叶片H₂O₂含量的增加，并提高了SOD、APX、CAT、DHAR、MDAR和GR活性；干旱胁迫下，EBR处理显著诱导了辣椒叶片抗氧化酶活性的增加，并抑制了H₂O₂和MDA含量的上升；EBR处理也促进了cAPX和MDAR等抗氧化酶基因的表达，以及WRKY3、WRKY6和MYB等转录因子的表达。由此认为，适宜浓度的外源EBR可能是通过信号分子H₂O₂调控辣椒叶片中WRKY和MYB等转录因子的表达以调控相关耐旱基因表达，增强细胞的抗氧化酶活性，减轻干旱造成的膜质过氧化伤害，从而增强了辣椒幼苗的耐旱性。

Abstract:We studied the effects of exogenous 24-epibrassinolide(EBR) on H₂O₂ and MDA content, antioxidant enzymes activities, and the expression of drought-tolerance relative genes in pepper(Capsicum annuum L.) under drought stress. The results showed that 0.1 μmol·L^-1 EBR induced H₂O₂ producing slightly, and significantly promoted the activities of SOD, APX, CAT, DHAR, MDAR and GR in leaves of pepper. While EBR significantly increased antioxidant enzymes activities, and alleviated H₂O₂ and MDA content in leaves of pepper under drought stress. EBR also induced the expression of antioxidant enzymes(cAPX and MDAR) and transcription factors(WRKY3, WRKY6 and MYB) genes. It was considered that the suitable exogenous EBR(0.1 μmol·L^-1) enhanced drought tolerance in pepper seedling maybe through induction of droughttolerance relative genes expression and activations of antioxidative enzymes, and H₂O₂ signal was involved in EBR-induced drought-tolerance relative genes expression.

---