Determination of in vitro activity of Panomycocin against Botrytis cinerea

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2015

Öğrenci: NİHAL YERLİ

Danışman: KADRİ FATİH İZGÜ

Özet:

Grey mold disease is one of these postharvest decays. Especially grapes are infected by Botrytis cinerea known as a causal agent of the grey mold disease. Some fungicides are used to control this disease. However, they cause funcide- resistant strains of the pathogens and make hazardous for human health and environmental safety. Therefore, The killer yeasts are considered as promising alternative antifungal agents among other biocontrol agents. Pichia anomala which is a killer yeast secretes the K5 type yeast killer protein called Panomycocin. The K5 type yeast killer protein has exo-β-1,3 glucanase activity and is stable at pH’s and temperatures appropriate for its biocontrol usage. The goal of the research is to determine the inhibition effect of the K5 type yeast killer protein on B. cinerea strains including type strain B. cinerea (DSMZ 5145) isolated from Italy and other 5 B. cinerea strains isolated from different fields in Tekirdağ. This inhibition activity of the K5 type yeast killer protein was known from broth microdilution assay based on CLSI (Clinical and Laboratory Standards Institue) M38-A and found to be highly effective on B. cinerea strains. The difference of the growth inhibition of B. cinerea strains in 96-well plates was determined with inverted microscope after 72 hours. The K5 type yeast killer protein with exo-β-1,3 glucanase activity resulted in vi physiological and morphological changes in the hyphae by causing coagulation and destruction of the protoplasm. The most effective growth inhibition was observed with 2048µg/ml of the K5 type yeast killer protein. MIC2 value of the K5 type yeast killer protein was 512µg/ml. The results showed that P. anomala secreting the K5 type yeast killer protein would be used as a biocontrol agent for prevention of grey mold disease in grape fields.