Biotic and abiotic stresses are major limiting factors for plant growth and development, and B-BOX proteins play crucial roles in plant growth and development and stress response. A previous study found that the BDBBX21 gene in Bambusa pervariabilis × Dendrocalamopsis grandis was significantly induced under adversity stress. In this study, the BDBBX21 gene was further identified and analyzed by bioinformatics analysis. Overexpressing BDBBX21 plants under pathogen stress had significantly lower incidence and disease index and showed higher chlorophyll, phenylalnine ammonialyase, and malondialdehyde contents compared to wild-type plants. Enzyme activities such as peroxidase and superoxide dismutase and expression levels of stress-related genes were significantly higher in BDBBX21 overexpression plants under drought, salt, and cold stress. These results indicated that BDBBX21 positively regulated the stress resistance of transgenic plants. Meanwhile, the exogenous jasmonate (JA) induction assay revealed that the transgenic BDBBX21 plants were significantly more sensitive to JA compared with the wild-type plants, and the expression of genes related to the JA signaling pathway was regulated by the BDBBX21 gene, which indicated that BDBBX21 positively regulated the plant resistance by participating in the JA signaling pathway. These findings improve our understanding of the response to adversity stress in Bambusa pervariabilis × Dendrocalamopsis grandis and provide a key candidate gene for molecular breeding for resistance in this species.

中文翻译：

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杂交竹 （Bambusa pervariabilis × Dendrocalamopsis grandis） 的 BDBBX21 基因通过茉莉酸信号通路正向调控转基因植物的逆境胁迫抗性


生物和非生物胁迫是植物生长发育的主要限制因素，B-BOX 蛋白在植物生长发育和胁迫反应中起着至关重要的作用。先前的一项研究发现，Bambusa pervariabilis × Dendrocalamopsis grandis 的 BDBBX21 基因在逆境胁迫下被显著诱导。本研究进一步鉴定了 BDBBX21 基因，并通过生物信息学分析进行了分析。与野生型植物相比，在病原菌胁迫下过表达BDBBX21植物的发病率和病害指数显著降低，叶绿素、苯丙氨酸解氨酶和丙二醛含量较高。在干旱、盐渍和寒冷胁迫下，过氧化物酶和超氧化物歧化酶等酶活性以及胁迫相关基因的表达水平在BDBBX21过表达植株中显著升高。这些结果表明，BDBBX21正向调节转基因植株的抗逆性。同时，外源茉莉酸酯 （JA） 诱导试验显示，与野生型植物相比，转基因 BDBBX21 植物对 JA 的敏感性显著更高，且与 JA 信号通路相关的基因表达受 BDBBX21 基因调控，表明BDBBX21通过参与 JA 信号通路正向调控植物抗性。这些发现提高了我们对 Bambusa pervariabilis × Dendrocalamopsis grandis 对逆境胁迫反应的理解，并为该物种的抗性分子育种提供了关键的候选基因。