Study Of Diversity Of Trichoderma Isolated From East China

Trichoderma spp. have wide applications in industry, agriculture, environmentalprotection, especially in the biological control of plant diseases in agriculture. Until now,more than 100 kinds of Trichoderma biological control agents or fertilizer products have beenregistered for a large scale commercial use in the world. The investigation on diverstiy ofTrichoderma resouces from different levels is greatly significant for human effectivelydiscovering, utilizing and protecting Trichoderma resources.and particularly benefit us themore understanding of biocontrol mechanism and ecological functions of Trichoderma.Currently genus Trichoderma includes 89 species in the world, in which only 24 species werefound in China. No work are carried out for clearing the situation of Trichoderma resources inEast China before our present work. We have collected 287 soil samples from East China andisolated 1026 strains of Trichoderma of which 13 species of Trichoderma were identified, andTrichoderma koningiopsis is identified as a new record species in China. Trichodermaharzianum is a dominant species in East China. Meanwhile we identified the biologicalcharacteristics and the geographical distribution of representative strains of Trichodermaislolated east-nationwide, and the diversity of peptaibols of several selected species as well asgenetic diversity of T. harzianum. The results generally showed that Trichoderma showedsignificant ecological, biochemical and genetic diversity.Further analysis with AFLP combined with four genes ech42,chit33,tef1α1α,ITSindicated that a high degree of intraspecific diversity presence in T.harzianum. The differenceamong selected Trichoderma species in chitnase and secondary metabolites profiles weredetected, which consequently laid the solid foundation for efficiently screening Trichoderma strains with biocontrol function and establishing collection of Trichoderma resources. Theresults showed that there was a varied activites in major chitinase present in 13 species ofTrichoderma and activites in chitinase are closely related to antagonistic ability. Trichodermawas demonstrated to be capable of producing a variety of secondary antagonistic metabolites,and PrPs was one of peptaibols identified using HPLC/MS in 6 Trichoderma strains. A totalof 16 kinds of PrPs were identified and then revealed a certain extent of diversity amongtested strains. The antimicrobial peptides secreted from Trichoderma are major functionalfactors inhibitory to pathogen.