落叶松-杨栅锈菌在感病杨树寄主上发育过程的组织学研究

采用荧光染色技术、光学显微镜和电子显微镜技术,系统研究了落叶松-杨栅锈菌在感病杨树叶片上的发育过程。结果表明,在侵染前期（接种12h以内）,锈菌夏孢子在杨树叶片上萌发,利用芽管或附着胞穿透叶表气孔后形成气孔下囊,进而在胞间产生侵染菌丝。进入活体营养生长阶段（接种后24-96h）,锈菌不断产生大量吸器来满足营养需求的同时,侵染菌丝在叶肉细胞间隙蔓延分枝生长至形成菌落结构。最终在产孢阶段（接种120h之后）产孢菌丝分化形成的夏孢子在表皮下聚集成堆,待成熟后突破表皮显露出来。

Histological studies on asexual development of Melampsora larici-populina in a susceptible poplar cultivar

The process of asexual development of Melampsora larici-populina on susceptible poplar leaves was investigated by fluorescence-staining technique associated with light and electron microscopy in detail. The observation showed that during the early phase of infection (within 12 hours post-inoculation, hpi), urediniospores germinated to produce germ tubes on poplar leaf surface, then penetrated the leaf stomata, formed substomatal vesicles and intercellular infection hyphae. After entering into the period of biotrophic growth (from 24 hpi to 96 hpi), the number of haustoria increased for nutrient acquisition and intercellular infection hyphae grew extensively into colonial structures in the intercellular space of foliar mesophyll. Finally, urediniospores differentiated from the sporogenous cells gathered into the uredinia under the leaf epidermis, and the uredinia erupted from the leaf epidermis when matured during the phase of uredinial formation (after 120 hpi).