Studies on fungal-parasite and fungal-borne viruses

点击翻译按钮获取中文摘要

( <I> ) Fungal parasitic viruses: Fungal viruses were screened over 600 fungal isolates 103 genus, 200 species) mainly phytopathogenic fungi. In the coures of this experiment, 41 new viruses were detected from 35 species and 7 known viruses were recognized from 6 species, suggesting that fungal viruses are wide-spread among various of these microorganisms. Direct negative staining method was shown to be the most efficient technigue to detect fungal viruses. Most of the viruses used in this study were purified from their hosts and morphological and physicochemical properties were examined. Some of them were multi component due to the differences in nucleic acid contents. Double-shell capsid structure was observed in 4 viruses and two of them posssed spikes at the 12 vertices, seemed to be taxonomically important. Serological properties of the fungal viruses were tested using virus antiserum against 7 viruses and two of them were sero-logically related with each other. Intracellular appe … More arance of each viruses were studied. Usually, viruses were recognized as both diffused and aggregated or crystalline arrays within the cytoplasm or vacuole. In two cases, specific matrix regions were observed in the cytoplasm. Fungal viruses seemed to be classified into two classes of particle diameter of 25-30nm group and 35-45nm group according to their physicochemical properties and particle sizes. ( <II> ) Fungal-borne viruses: 10 soil-borne plant viruses transmitted by Olpidium and Polymyxa were studied. Classification of each viruses were examined in regard to their geographical distribution, morphology of the virus particles, physicochemical properties and intracellular appearances. Consequently, elongated viruses were divided into following 3 groups, (1) SBWMV,BNYVV,BNMV group, (2) BYMV, WYMV group, (3) LBVV,TSV group. And spherical viruses were divided into following 3 groups, (1) TNV group, (2) PSNV,MNSV group, (3) SV group , respectively. Varieties of fungal-borne viruses were evident by this comparative study and classification groups. Less