VIGS技术初步鉴定RgMLO6和RlMLO7基因对白粉病的负调控功能

The negative regulation of RgMLO6 and RIMLO7 genes on powdery mildew was preliminarily identified by VIGS technique

为了探讨蔷薇科植物MLO基因在抗白粉病中的作用,研究应用病毒诱导的基因沉默技术(virus induced gene silencing,VIGS)抑制了大花香水月季RgMLO6基因和长尖叶蔷薇RlMLO7基因的表达,随后接种白粉菌对这2个基因进行抗性鉴定.研究发现在VIGS载体转化植株叶片20 d后,RgMLO6和RlMLO7基因的相对表达量显著下降了80%~90%,沉默效果明显.分别对2个基因沉默后的嫩叶进行白粉病抗性鉴定,大花香水月季和长尖叶蔷薇的抗性水平较对照组均提高.显微镜观察白粉菌接种2个基因沉默后植株叶片中菌丝体的生长情况,整体表现出沉默植株叶表皮细胞上的白粉菌生长较对照组生长缓慢.结果表明RgMLO6与RlMLO7基因对蔷薇科植物的白粉病有负向调控作用.

To investigate the role of MLO gene in powdery mildew resistance in Rosaceae,virus-induced gene silencing(VIGS)was used to inhibit the expression of RgMLO6 gene in Rose odorata var.gigantea and RlMLO7gene in Rose longicuspis var.longicuspis.Then mildew was inoculated to identify the resistance of these two genes.The results showed that the relative expression levels of RgMLO6 and RlMLO7 genes in silenced plants decreased by 80%-90%after 20 days of VIGS vector transformation.The powdery mildew resistance of the young leaves silenced by the two genes was identified,and the resistance levels of Rosa odorata var.gigantea and Rosa longicuspis var.longicuspis were improved compared with the control group.The growth of mycelium in leaves of powdery miltiorrhiza after inoculated with two genes was observed under microscope.The growth of powdery mildew on leaf epidermis cells of silent plants was slower than that of control group.The results showed that RgMLO6 and RlMLO7 genes had negative regulation on powdery mildew in Rosaceae.