稻粒黑粉病病原菌分类地位的初步研究

A Preliminary Study on Taxonomic Status of Pathogenic Fungus of Rice Kernel Smut

稻粒黑粉病是我国杂交稻制种田的重要病害,其病原菌的归属问题目前仍有分歧。通过对其病原菌细致研究和试验观察发现:稻粒黑粉菌的冬孢子在光照条件下可大量萌发;萌发后产生20—60枚线状小孢子;小孢子之间不结合;小孢子在PSA培养基上可产生腊肠状和针状次生小孢子。将这些性状同Neovossia属的典型种N.moliniae(Thuem)Ko-ern及Tilletia属进行全面比较,认为将稻粒黑粉菌定名为Neovossia horrida(Tak.)Padwick & AzmatKhan更为确切。

Rice kernel smut (RKS) is an important disease in hybrid rice seed producing fields. It has been debated whether the pathogenic fungus of RKS shoud belong in the genus Tilletia or in Neovossia. In order to clear up the taxonomic status of this fungus a detailed study was carried out on its characters. It was found that a large number of chlamydospores could germinate under the condition of light, and at the end of promycelia, 20-60 filiform sporidia were produced. No conjugation of sporidia was observed. Two kinds of secondary sporidia could be produced when the fungus was cultured in the PSA medium. Based on an overall comparison between the typical species of the genus Neovossia ,N. molinzae(Thuem) Koern, the genus Tilletia and the problem fungus,it is suggested that the pathogenic fungus of RKS should be named Neovossia horrida (Tak) Pad wick & Azmat Khan..