短柄草柄锈菌在感病寄主二穗短柄草上发育过程的组织学研究

Histological studies on the development of Puccinia brachypodii in the susceptible host Brachypodium distachyon

本研究采用荧光染色和荧光显微镜技术,系统研究了短柄草柄锈菌Puccinia brachypodii(分离系F-Co和K-Ki)在感病二穗短柄草Brachypodium distachyon自交系Bd21-3叶片中的发育过程。荧光显微镜观察结果表明,接种12–18h时,病原菌通过芽管侵入短柄草叶表皮气孔后形成气孔下囊,产生初生菌丝并形成吸器母细胞,进而侵入植物细胞形成吸器;接种24–48h后,病原菌初生菌丝分支并形成次生菌丝;接种72h后,短柄草锈菌开始形成菌落。F-Co的发育过程快于K-Ki,在120–216 h时,F-Co的菌落扩展面积明显高于K-Ki。本研究证实F-Co、K-Ki和二穗短柄草均为亲和互作。

The development process of Puccinia brachypodii(isoates F-Co and H-Ki)in the leaves of Brachypodium distachyon inbred line Bd21-3 was systematically studied by fluorescence-staining technique associated with fluorescence microscopy.The observation showed that the two isoates germinated to produce germ tubes on the leaf surface,then penetrated into stomata,formed substomatal vesicles and produced primary hyphae to form haustoria mother cells which invaded plant cells to form haustoria in 12–18 hours of post-inoculation(hpi).The primary hyphae branched to form secondary hyphae in 24–48 hpi.Some colonies formed in 72 hpi.The development process of P.brachypodii F-Co was faster than that of H-Ki,resulting in that the colony expansion area of F-Co was significantly higher than that of H-Ki in 120–216 hpi.This study confirms that both F-Co and H-Ki form compatible interactions with B.distachyon.