Studies On Forest Tree Parasitic Fungi Diversity In Lao-Ye-Ling Mountains, Jilin Province, China

Species diversity, community diversity of forest tree parasitic fungi and relation between season and parasitic fungi from the Lao-Ye-Ling Mountains, Jilin Province, China were studied systematically in this paper.In the species diversity study, more than 340 specimens were collected and 210 species of them were identified, which belonged to 6orders 10 families and 24 genera. The diversity catalogue of these species were arranged according to Ainsworth & Bisby' Dictionary of the Fungi.(1995,8th).The results of community diversity study showed that there were differences in parasitic fungi species diversity among the three types of plant communities studied. Among them, the richest parasitic fungi species diversity existed in the "Acer spp.+Tilia spp.+Pinus koraiensis- Lonicera spp.+Crataegus spp.-Equisetum hiemale" community (typeⅠ), which included 42 species and occupied 87.5% of the total species. We collected 287 specimens from typeⅠ, which occupied 66.0% of total specimens. The numbers of Melampsora larici-epitea, Cercospora corylina, Passalora lonicerigena, Marssonina mali, Ascochyta pruni, Phyllosticta crataegicola and Phyllosticta vulgaris were the most, we got 9 specimens respectively. In the "Fraxinus mandshurica+ Phellodendron amurense+ Acer spp.- Dryopteris crassirhizoma+ Equisetum hiemale" community (typeⅡ), which included 25 species and occupied 52.1% of the total species. We collected 115 specimens from typeⅡ, which occupied 36.4% of total specimens. The numbers of Cercospora phellodendri and Marssonina populicola were the most, we got 7 specimens and 8 specimens respectively. In the "Quercus mongolica- Equisetum hiemale" community (typeⅢ), which included 12 species and occupied 25% of total species. We collected 38 specimens from typeⅢ, which occupied 8.7% of total specimens. The numbers of Phyllosticta vesicatoria were the most, we got 8 specimens. In the different plant community types, the indexes of H (Shannon-Wiener,1949), E (Pielou, 1975,1977) and R (Menhinick, 1964) of parasitic fungi community diversity wereⅠ＞Ⅱ＞Ⅲ. This result showed that the ecological factors of type I were beneficial for parasitic fungi to infect and grow. The dynamic characteristics of parasitic fungi accorded with the Intermediate Disturbance Hypothesis.There were differences in parasitic fungi species diversity among the different canopies of three types of plant communities. In communityⅠ, the richest parasitic fungi species diversity existed in the low level of canopy, which included 42 species. We collected 172 specimens from the low level of canopy in typeⅠ, which occupied 59.9% of the total specimens in typeⅠ. In the middle level of canopy, which included 40 species. We collected 82 specimens from the middle of canopy in typeⅠ, which occupied 28.6% of the total specimens of typeⅠ. In the high level of canopy, which included 28 species. We collected 33 specimens from the high of canopy in typeⅠ, which occupied 11.5% of the total specimens of typeⅠ. In the low level of canopy of the communityⅡ, which included 25 species. We collected 82 specimens from the low level of canopy in typeⅡ, which occupied 71.3% of the total specimens in typeⅡ. In the middle level of canopy, which included 16 species. We collected 24 specimens from the high of canopy in typeⅡ, which occupied 20.7% of the total specimens of typeⅡ. In the high level of canopy, which included 9 species. We collected 9 specimens from the high of canopy in typeⅡ, which occupied 7.8% of the total specimens of typeⅡ. In the low level of canopy of the communityⅢ, which included 12 species. We collected 27 specimens from the low level of canopy in typeⅢ, which occupied 71.1% of the total specimens in typeⅢ. In the middle level of canopy, which included 7 species. We collected 9 specimens from the high of canopy in typeⅢ, which occupied 23.7% of the total specimens of typeⅢ. In the high level of canopy, which included 2 species. We collected 2 specimens from the high of canopy in type Ill, which occupied 5.3% of the total specimens of typeⅢ. The indexes of parasitic fungi diversity in the different canopies in three plant communities were low level＞middle level＞high level. This showed that the ecological factors were beneficial for parasitic fungi of low level to infect and grow.The results of relation between parasitic fungi diversity and seasonal dynamic changes showed that the number and species of parasitic fungi maintained the highest level from the first ten-day period of August to the last ten-day period of September, especially in the last ten-day period of August in a year. The optimum period for parasitic fungi was the days, which has day highest temperature between 22~C and 30℃and day lowest temperature between 10℃and 18℃. And in a year, the optimum period for parasitic fungi was the days, which has day humidity between 64% and 96%.