胡杨和灰叶胡杨锈菌夏孢子形态和侵染结构观察

 借助直接观察、显微和超微结构观测等手段，对胡杨和灰叶胡杨锈病显症叶片、锈菌夏孢子的形态、孢子萌发和侵染结构进行了观测。结果表明，胡杨和灰叶胡杨的锈菌夏孢子堆、夏孢子形态结构相似；夏孢子堆散生于叶片正反两面，近半球形或半椭球形，呈橙黄色或金黄色；夏孢子散落分布于叶片正反两面，圆形或卵圆形，透明、橙黄色，厚壁，单胞，表面密生刺瘤；胡杨和灰叶胡杨锈菌夏孢子的长轴和短轴长度、刺瘤高度及刺瘤间距四项指标均无显著性差异；夏孢子萌发产生芽管后形成菌丝，通过叶表气孔直接侵染叶片，以菌丝的形式在叶片组织内扩展。

Morphology of uredospores and infecting structure of Melampsora pruinosae in Populus euphratica and P. pruinosa

The morphology and germination of uredospores, as well as infecting structure of Melampsora pruinosae in Populus euphratica and P. pruinosa were studied by means of dry examination, microscopy, and ultra-structure observation. Results showed that the uredia and uredospores of M. pruinosae on P. euphratica and P. pruinosa appeared to be similar in morphology and structure. The uredia revealed hemispherical or half ellipsoidal masses with orange yellow or golden yellow color on both sides of diseased leaves. Uredospores were unicellular and thick-walled spherical or ovoidal shape, transparent and orange yellow, scattering on both sides of diseased leaves. There were no significant differences in four parameters of uredospores shape, including length, width, height of projection, and intervals of projections. The hyphae, formed by germ tubes from germinated uredospores, infected the leaves through stomata, and expanded in the leaves in both P. euphratica and P. pruinosa.