Study On Isolation, Identification And Latent Biological Control Capability Of Fungus Chaetomium Sp.

Chaetomium spp. has the ability of effectively inhibit plant pathogenic fungi, and has been extensively applied throughout the world as plant disease bio-control agent. However, this species is sensitive to chemical fungicide, which limits its application in integrated pest management (IPM) system where chemicals, bio-control agents and other methods are all involved. To improve Chaetomium's fungicide resistance without sacrificing its bio-control function, genetic transformation techniques provide a useful approach. The purpose of this research was to isolate and identify Chaetomium from contaminated Chengxlv hybrid bamboo(Bambusa pervaiabilis McClure × Dandrocalamopsis daii Keng f.) culm, and determine its biological characteristics, virulence, and antagonism capability. The results from this research could be served as theoretical evidences for the following genetic transformation experiment.Chaetomium was isolated from Chengxlv hybrid bamboo and cultivated on potato saccharose agar (PSA). Identification was carried out by its biology characteristics, and measurements of colonies, ascomata, ascomatal hairs, asci and ascospores. Based on the comparisons with approximately 20 species specimens documented, we found that the isolated Chaetomium in our research was significant different from others. We concluded that this species, temporarily named Chaetomium sp., is new and has never been documented domestically.There were variations of the quantity Chaetomium sp. appeared in different seasons, tissues, and ages. Among four seasons, Chaetomium sp. occurred most often in summer and fall, and least in winter. They most appeared on perennial Chengxlv hybrid bamboo than one-year old tender bamboo tissue. It also showed that Chaetomium sp. was most distributed in outer surface of the bamboo tissue and gradually decreased to its inner tissue.