| Some important members of seven genera in Rhytismataceae were systematically studied from morphology, developmental biology, ecology and distribution. And intraspecific and similar interspecific RAPD analysis of important species was applied to Hypoderma, Coccomyces and Rhytisma. 200 samples collected from the mountain of south Anhui, Hefei and some ones deposited in Anhui Agricultural University Forest Protection (AAUFP) were examined and isolated partly. 11 species of 7 genera including Lophodermium, Ploioderma, Hypoderma, Soleella, Bifusella, Rhytisma and Vladracula were identified according to the taxonomic principles of Darker (1967) and Cannon & Minter (1986). There are 2 new species: L. illiciicola and L. osmanthi besides 9 species known from the world. Dichotomous key to these species were compiled. Morphological characteristics were described and illustrated, and habits, hosts and distributions were recorded for the species. Living fungi collected from the mountain of south Anhui and Hefei were isolated in MA culture media by tissue isolation technics, and 18 strains of different hosts were obtained, which involved 13 species of 4 genera: Hypoderma, Coccomyces, Rhytisma and Vladracula including 2 uncertain species of Hypoderma. Not only fungi of different genera but also different fungi of same genera, even same species of different hosts were different in growth rate, colony color, colony size and mature period. Each strain was periodically described detailedly. As a result, few of the species formed pycnidia, and none of the species produced ascocarps during culture. 15 strains of Hypoderma, 10 strains of Coccomyces, 2 strains of Rhytisma and Vladracula annuliformis from different hosts were provided to extraction of genomic DNA, selection of optimal PCR amplification system and intraspecific and similarly interspecific RAPD (random amplified polymorphic DNA) analysis. RAPD technics characterized with no strict limitation to primers, strong polymorphy and sensitive examination have interior stability and repeatability, so there is a necessary to find a RAPD reaction system suitable for the experiment in order to promote stability and repeatability. The influencing factors and experimental parameters on RAPD were studied in the thesis, such as template, dNTPs, Mg2+, primer, Taq DNA polymerase and annealing temperature, annealing time, elongation time and cycle numbers. As a result, optimal PCR amplification system included 10×PCR buffer,2.0mmol/L MgCl2,0.2mmol/L dNTPs,0.3μmol/L random primers,100ng/μl DNA template and 1U Taq DNA polymerase. RAPD analysis was applied to 15 strains of Hypoderma from different hosts using 15 primers selected from 100 random primers, which amplified 136 sites including 134 polymorphic sites, accounting for 98.5%. Most 13 bands were amplified by primer S96 and the least 5 bands were amplified by primers S11 and S379. The length of most amplified fragments ranged from 250 to 2000bp. These fragments were used in genetic variation analysis of intraspecies and similar interspecies. 15 strains of Hypoderma were classified to 4 groups (A, B, C and D) in the position of 4.68 genetic distance of dendrogram using UPGMA method. The results were accorded with morphologic classification and culture characters. At the same time, 10 strains of Coccomyces from different hosts were studied by RAPD analysis using 14 selected primers. There are 134 polymorphic bands in 137 whole ones accounting for 97.8%. dendrogram was constructed by using UPGMA method. 10 strains of Coccomyces were classified to 3 groups (I, II and III) in the position of 5.3 genetic distance and group III includes 2 subgroups. It is the same to morphologic classification. Furthermore, Two similar genera (Rhytisma and Vladracula) were studied by RAPD analysis and similarity between Rhytisma punctatum and Vladracula annuliformis reached 91.9%. And they are similar extremely in morphology, anatomy and culture characters. So it can conclude preliminarily that Vladracula annuliformis is placed in Rhytisma. Vladracula sha...
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