Interactions between Trichoderma harzianum strains and some soilborne plant pathogens (Gaeumannomyces graminis var. tritici, Fusarium culmorum and F. moniliforme) were studied on PDA medium. All T. harzianum strains tested produced a metabolite that inhibited growth of plant pathogenic fungi on PDA medium. | Turk J Biol 28 (2004) 111-115 © TÜB‹TAK In Vitro Antifungal Activity of Strains of Trichoderma harzianum Çi¤dem KÜÇÜK, Merih KIVANÇ Department of Biology, Faculty of Science, Anadolu University 26470 Eskiflehir - TURKEY Received: Abstract: Interactions between Trichoderma harzianum strains and some soilborne plant pathogens (Gaeumannomyces graminis var. tritici, Fusarium culmorum and F. moniliforme) were studied on PDA medium. All T. harzianum strains tested produced a metabolite that inhibited growth of plant pathogenic fungi on PDA medium. When grown in liquid cultures containing laminarin, chitin or fungal cell walls as sole carbon sources, 2 strains of T. harzianum produced 1,3-β-glucanase and chitinase in the medium. Higher levels of these enzymes were induced by T. harzianum T15. Key Words: Trichoderma harzianum, plant pathogenic fungi, lytic enzymes Trichoderma harzianum ‹zolatlar›n›n In Vitro Antifungal Aktivitesi Özet: PDA geliflme ortam›nda, baz› toprak kökenli bitki patojenleri (Gaeumannomyces graminis var. tritici, Fusarium culmorum ve F. moniliforme) ve Trichoderma harzianum streynleri aras›ndaki interaksiyonlar çal›fl›lm›flt›r. Test edilen tüm Trichoderma harzianum streynleri, bitki patojeni funguslar›n geliflimini PDA ortam›nda inhibe eden uçucu metabolit üretmifllerdir. Karbon kayna¤› olarak laminarin, kitin veya fungal hücre duvar› içeren s›v› ortamda gelifltirildiklerinde, Trichoderma harzianum’un iki streyni ortamda 1,3β-glukanaz ve kitinaz enzimleri üretmifllerdir. Bu enzimlerin en yüksek düzeyleri Trichoderma harzianum T15 taraf›ndan üretilmifltir. Anahtar Sözcükler: Trichoderma harzianum, bitki patojeni funguslar, litik enzimler Introduction Gaeumannomyces graminis var. tritici is the causal agent of take-all disease, the most important damaging root disease of wheat worldwide (1). Fusarium culmorum and F. moniliforme specifically attack many agricultural crops causing foot and root rot (2). Alabouvette et al. (3) showed that
