小麦PR-1、PR-2、PR-5基因的白粉菌和水杨酸诱导表达分析及白粉病抗性研究(英文)

Expression Analysis of Wheat PR-1,PR-2,PR-5 Activated by Bgt and SA,and Powdery Mildew Resistance

病程相关蛋白基因PR-1、PR-2和PR-5是植物抗病基因介导的抗病反应和系统获得抗性(systemic acquired resistance,SAR)中的标志基因。为了研究病程相关蛋白基因和水杨酸在小麦(TriticumaestivumL.)抗白粉病反应中所起的作用,以抗白粉病和感白粉病小麦品系为材料,在白粉病菌(Blumeria graminisf.sp.tritici,Bgt)诱导不同时间,或水杨酸处理不同时间后,用半定量RT-PCR技术检测了小麦叶片中PR-1、PR-2和PR-5基因的表达变化。结果表明,白粉病菌的侵染激活和显著增强了病程相关蛋白基因PR-1、PR-2和PR-5在周麦18中的转录。与感病品系相比,PR-1和PR-5在抗病品系中转录激活得更快、更强。水杨酸处理显著激活了PR-1和PR-5的转录,但对PR-2的转录影响不大。白粉病菌和水杨酸均能显著激活和增强PR-1和PR-5的表达,但白粉病菌的作用更强,说明PR-1和PR-5基因在小麦抗白粉病反应中起重要作用。PR-1和PR-5可以作为小麦SAR的标志基因。水杨酸处理后周麦18和中国春的白粉病抗性得到提高,提示水杨酸在小麦抗白粉病信号传导途径中起一定作用。

Pathogenesis-related protein genes（PRs） of PR-1,PR-2 and PR-5 are the marker genes of plant disease resistance（R） gene-mediated resistance and systemic acquired resistance（SAR）.To investigate the roles of PR genes and salicylic acid（SA） in wheat（Triticum aestivum L.） powdery mildew resistance reaction,the expression patterns of PR-1,PR-2 and PR-5 in seedling leaves of susceptible and resistant wheat cultivars or lines were analyzed by semi-quantitative RT-PCR after Blumeria graminis f.sp.tritici（Bgt） infection or SA treatment.The results showed that the transcribing of PR-1,PR-2 or PR-5 was significantly enhanced by Bgt infection in Zhoumai 18.The expressions of PR-1 and PR-5 were activated more quickly and strongly in resistant wheat than in susceptible wheat.SA significantly activated the transcriptions of PR-1 and PR-5,but it had less effect on PR-2.Both Bgt and SA could significantly upregulate the expressions of PR-1 and PR-5,but the effect of Bgt was stronger than that of SA.Therefore,PR-1 and PR-5 played important roles in wheat powdery mildew resistance.PR-1 and PR-5 may be considered as the marker genes for SAR in wheat.With a role in wheat powdery mildew resistant signal transduction cascades,SA application increased the powdery mildew resistance of Zhoumai 18 and Chinese Spring.