不同低反应型抗锈单基因系与小麦叶锈菌互作的组织病理学比较研究

A Comparative Histopathological Study of theExpression of Lr9, Lr29 and Lr27 Alleles forLow Reaction Resistance to Wheat Leaf Rust

用荧光显微技术和微分干涉技术比较研究了３种不同低反应型抗锈单基因系与小麦叶锈菌互作的组织病理学表现。近免疫单基因系Ｌｒ９呈现为早期过敏性坏死反应无菌丝同步坏死型；高抗单基因系Ｌｒ２９呈现为早期过敏性坏死反应有菌丝同步坏死型；中抗单基因系Ｌｒ２７呈现为非亲和性反应的延迟表达型。以上结果证明不同类型的低反应型组合寄主细胞坏死的起始时间和发生速度以及菌丝体扩展、吸器母细胞和吸器形成的受抑时间和受抑程度有明显差异。

The histopathological manifestation of interactions between Puccinia recondita fsp tritici and wheat near isogenic lines possessing Lr9,Lr29 and Lr27 was comparatively studied with fluorescent microscopy and differential interference contrast microscopy It was not untill after the first haustorium was initiated that resistance could be detected The timing and degree of resistance were dependant upon the specific host-pathogen combination Nearly immune line Lr9 showed early hypersensitive reaction with few mycelia observed; High resistant line Lr29 expressed early hypersensitive reaction with many mycelia observed;While moderate resistant line Lr27 exhibited delayed response of incompatibility Findings suggested a secondary role for host cell necrosis in the expression of Lr27 allele, while in the expression of Lr9 and Lr29 alleles, host necrosis played a determinant role It was concluded that each low reaction type showed its own characteristics, manifesting as the timing and speed of hypersensitive reaction as well as the role of host necrosis in inhibiting the rust growth