Isolation of Trichoderma Spp. and determination of their antifungal, biochemical and physiological features

Abstract

Trichoderma spp.'nin biyolojik kontrol ajani olarak kullanildigi genellikle bilinmektedir. Bu çalismada, 31 degisik toprak örneginden Trichoderma izolati izole edilmistir. Toprak örnekleri Eskisehir ve çevresinden alinmistir. Bu izolatlarin farkli bitki patojeni funguslara karsi antifungal, biyokimyasal ve fizyolojik etkileri arastirilmistir. Trichoderma harzianum T9, T10, T15 ve T19'un filtratlari bitki patojenlerinden Fusarium culmarum, F. oxysporum, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Gaeumannomyces graminis var. tritici ve Drechslera sorokiniana'a etkili olmustur. T. harzianum T19, birden fazla bitki patojenini inhibe etmistir. F. oxysporum, filtrat deneylerinde en dirençli patojen olarak belirlenmistir. Tüm izolatlar, jelatin hidrolizi, inhibitör maddelerde, farkli pH ve sicaklik düzeylerinde gelismeleri gibi fizyolojik testlerde farkli özellikler göstermislerdir.

It is well known that Trichoderma spp. can be used as a biological control agent. In this study, Trichoderma isolates were obtained from 31 different Eskisehir soil samples. The biocontrol and antifungal effects of these isolates against various plant pathogen fungi were determined. We found that all filtrates of Trichoderma harzianumT9, T10, T15 and T19 were effective against plant pathogens Fusarium culmarum, F. oxysporum, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Gaeumannomyces graminis var. tritici and Drechslera sorokiniana. Among these isolates, T. harzianum T19 showed a wide range of inhibitory effects on plant pathogens. F. oxysporum was found to be the most resistant to the filtrates of the strains above. All isolates showed different behaviors depending on the physiological tests carried out such as growth in the presence inhibitory substrates, pH limits of growth and hydrolysis of gelatin. T. harzianum isolates were grown on the chitin, which is the sole carbon source. The chitinase activity determined from T. harzianumT15 by SDS-PAGE was nearly 73 kDa.