摘要
本文利用透射电镜 ,首次对玉米不同抗性寄主与肿囊腐霉 (Pythium inflatum)相互作用中的寄主反应及菌丝在寄主内的发展进行了系统研究。结果表明 :玉米苗期根部接种后 ,孢子迅速萌发成菌丝在根表蔓延 ,随即穿透根表皮 ,进入表皮细胞、皮层甚至感病寄主的维管束组织。与此同时 ,寄主相应的反应迅速 ,寄主反应采取如下方式 :细胞壁的沉积物及乳突在真菌的入侵处形成 ,各种无定形物质或纤丝构成的质网包围入侵菌丝。沉积在寄主细胞壁上并在受侵染细胞内聚集的化合物可能是酚类物质 ,这些嗜锇酸的电子致密物是用来机械地加强细胞壁的强度及产生抗真菌的环境。寄主反应的早晚及程度的强弱决定着菌丝在寄主体内发展繁殖的程度及寄主抗性的强弱。
Two aspects of the interaction between maize roots and Pythium inflatum were investigated, the host's response to fungal invasion and the development of fungal hyphae in the tissues. After inoculation, the spores germinated and generated the hyphae, which developed over the root surface and then penetrated the epidermis, later the cortex and susceptible maize root vascular stele. During this period, the host generated obvious reactions to Pythium inflatum invasion, such as producing various types of cytoplasmic networks composed of amorphous materials or fibrils which surrounded the invading hyphae. Wall depositions and papillae frequently formed at sites of attempted fungal entry. Chemical compounds, possibly phenols, coated host walls and accumulated inside in invaded cells. It is likely that these substances, appearing osmiophilic or electron dense, mechanically reinforce the host's cell walls and create a fungitoxic environment for Pythium inflatum. In conclusion, evidence has been presented in the study that these defense reactions in resistant maize were expressed relatively early and intensively, and were thus efficient in repelling the attack.
出处
《植物病理学报》
CAS
CSCD
北大核心
2002年第3期241-246,共6页
Acta Phytopathologica Sinica
基金
国家"转基因植物专项基金 (ZJY- A- 0 1)
