稻粒黑粉菌对水稻不育系的侵染过程

Infection Process of Neovossia horrida in Male Sterile Rice

用Neovossia horrida的次生小孢子，在田间和离体接种水稻不育系的试验证明，病菌以菌丝从柱头直接侵入，经花柱到达子房的珠心组织。接种后8小时在子房中发现菌丝，第7天在种皮和糊粉层之间形成初生冬孢子，第9天冬孢子成熟。病菌在4个不育系上的侵染过程相似。病菌在无需授粉的条件下就能侵入、但只在胚乳能正常发育的水稻子房中形成冬孢子。

Male sterile rice plants were inoculated with secondary sporidia of Neovossia horrida in field and isolated in laboratory.It was found that the hyphae of fungus penetrated directly through the stigma to the style and finally to the ovary 8 hrs afterinoculation. The mycelia remained in nucellus tissue. The initial teliospore formed between the aleurone layer and seed coat7 days aftr inoculation, and it matured in 9 days. The infection process of Neovossia horrida in these four male sterile linesof rice was almost similar. Fungus might penetrated through stigma without pollination, but the formation of teliospore occured only in the normally developing endosperma.Keywods:Neovossia horrida Infection process Teliospore Ovary