小麦慢条锈性表达的超微结构特征

 用透射电镜研究了小麦品种慢条锈性表达的超微结构。结果表明,慢锈性具有与低反应型抗锈性相同的过敏性坏死反应特征,但慢锈品种中寄主叶肉细胞坏死数目较少,仅部分地阻抑了病菌的扩展,病菌受抑、坏死程度轻。慢锈品种寄主细胞对病菌入侵的反应除发生过敏性坏死反应外,还产生了防卫反应结构物质,但此物质明显比抗病品种的少。因此认为慢锈性可能与小种专化抗锈性具有相似的机制,只是强度较低。

Ultrastructure of Slow-rusting Expression of Wheat to Stripe Rust

The ultrastructure of wheat cultivars with slow-rusting resistance expression to the stripe rust, Pucciniastriiformis, was studied through TEM. The results show that slow-rusting has the same hypersensitive response characterswith the low infection type resistance, but the mesophyll cell necrotized less in number, thereby only partially inhibiting theextension of rust fungus, and the fungus being inhibited and necrosed slighter in degree. Apart from the occurrence ofhypersensitiveness, the response of the host cells in slow-rusting wheat cultivars to the infection of fungus also producesstructural materials associated with defense reaction, but distinctly less than that in resistant cultivars. Thus, it is suggestedthat the slow-rusting resistance might have a similar mechanism with the low infection type resistance of race specificity,but with lower intensity.