Studies On The Dendrocola Fungi On Pinus Armandii In Erlangshan Mountain, Sichuan Province

Pinus armandii Franch.which is fast-growth,good-timber,and abroad-distribution, is an important tree species for timber,also is one of main tree species in low-to-medium mountain regions in the southwest of China.It is a local five-needle pine of China,which has a very important status and function in the south forestry production of China. Dendrocola fungi are important parts in Pinus armandii Franch.plantation ecosystem, which occupy very important status in the whole Pinus arrnandii Franch.ecosystem.There are mang species of fungi on the surface of Pinus armandii Franch.,which form complex micro-ecosystem.With the basic principles of ecology and forest pathology,and technologies of microbiology,forest pathology,statistics,community ecology,this thesis was carried out to fred out the members of the dendrocola fungi in Pinus armandii Franch.,probed into the trends of species diversity and the relativity between diseases and species diversity,and screened antifungal fungi to Lophodermium conigeniurn and Phomopsis sp.from endophytic.The main results are follows:(1) Through isolating and culturing,41 species fungi were obtained from Pinus arrnandii Franch.needle,the advantage population are Lophodermium sp.,the abroad-distributing population are Phyllosticta sp.,Pestalotiopsis sp.,Alternaria sp.,and so on.21 species needle dendrocola fungi were obtained in spring,15 species were obtained in summer,29 species were obtained in autumn,12 species were obtained in winter.The species,quanti-ty and degree of species diversity of needle dendrocola fungi increased with the increase of needle age and decrease of crowns.The needle dendrocola fungi in spring and autumn was more active than that in summer and winter.We obtained 37 species fungi from bra-nch,Phomopsis sp.are the advantage fungi,Pestalotiopsis sp.,Alternaria sp.,Penicillium sp.,Botrytis sp.and Aspergillus sp.are abroad distributing.We obtained 25 species bran-ch dendrocola fungi in sping,20 species in summer,31 species in autumn,16 species in winter.The species,quantity and degree of species diversity of branch dendrocola fungi increased with the increase of branch age.The degree of species diversity in branch dend-rocola fungi are greatest in mid-crown,lower in top-crown,littest in low-crown.The branch dendrocola fungi in spring and autumn was more active than that in summer and winter.(2) The size of needle dendrocola community and degree of species diversity were affected more severely by season and crown than that by altiude and needle age.The size of branch dendrocola community and degree of species diversity were affected more severely by season,crown and branch age than that by altiude.The diversity and equality of needle dendrocola community decreased with the increase of needle age and decrease of crowns.The diversity of branch dendrocola community were greatest in mid-crown,lower in top-crown,littest in low-crown,and increaed with the increase of branch age.The equality of branch dendrocola community decreased with the increase of needle age and decrease of crowns.(3) The isolation rate of L.sp was proved to be related with the diversity and equality of needle dendrocola community.The worse the diversity and equality was,the higher the isolation rate of L.sp was,and the probability of needle falling on pine was bigger.The isolation rate of Phomopsis sp.was related with the diversity and equality of branch dendrocola community.The isolation rate of Phomopsis sp.decreased with the increasing of the diversity and equality.The relation between the isolation rate of pathogeny and the diversity and equality of dendrocola community was affected by needle(branch) age and crowns severely,and by altitude lightly.(4) Endophytic fungi were isolated from healthy needles with conventional isolation method and their antagonistic activities to some forest pathogens were surveyed.Seven-teen species of fungi in needles were obtained.By the method of dual culture,the result showed that the metabolites of Trichoderma.sp make unobviously antagonistic ability to Pestalotiopsis.sp and Lophodermium.Conigenu,but make obviously use to Phomopsis Sacc.Four kinds of metalbolites of Trichoderma.sp restrain bourgeon of spore of Pestalotiopsis sp..