MOLECULAR IDENTIFICATION OF Diplodia seriata De Not. CAUSING DIEBACK EFFECT ON GRAPEVINES AND EVALUATION OF in vitro EFFICACY OF FIVE DIFFERENT SYNTHETIC FUNGICIDES AGAINST THIS DISEASE

The aim of this study was to realize the molecular identification of Diplodia seriata De Not., a member of the Botryosphaericea family, isolated from 2-10 years old vines in vineyards showing symptoms of dieback disease. The susceptibility of the pathogen against the fungicides with the fosetyl-Al+triadimenol, azoxystorbin+difecanozole, fludioxanil+cyprodinil, metrafenone, fluopyram+tebuconazole combinations were evaluated. The isolates obtained from the root and crown parts of the vine samples were identified as D. seriata according to the morphological and molecular methods. In molecular identification, the ITS (Internal Transcribed Spacer) and TUB2 (β-tubulin) gene regions of the isolates were amplified by Real-Time PCR and the nucleotide sequences were obtained in these gene regions. After using the MEGA 7 software, ITS and TUB2 sequences were aligned and a combined phylogenetic tree was made. It has been molecularly confirmed that the D. seriata isolate has a 100% similarity index with Diplodia species according to the phylogenetic analyses. The mean effective concentration (EC50) values of fungicides used with different concentrations (0, 1, 3, 10, 30, 50, 100 μL mL-1) were determined by Probit analysis. Cyprodinil + fludioxonil showed the highest efficacy (100%) at a concentration of 1 μL mL-1. According to EC50 values, cyprodinil + fludioxonil (0.001 μL mL-1) was recorded as the most effective fungicide followed by fluopyram + tebuconazole (0.520 μL mL-1) and, azoxystrobin + difenoconazole (2.958 μL mL-1), respectively. Bu çalışmanın amacı, geriye doğru ölüm hastalığı belirtileri gösteren bağlardaki 2-10 yaşındaki asmalardan izole edilen Botryosphaericea ailesinin bir üyesi olan Diplodia seriata De Not.'nın, moleküler tanılamasını gerçekleştirmektir. Patojenin duyarlılığı, fosetil-Al+triadimenol, azoxystorbin+difecanozole, fludioxanil+cyprodinil, metrafenon, fluopyram+tebuconazole dâhil olmak üzere çeşitli fungisitlere karşı değerlendirilmiştir. Üreticiler tarafından getirilen asma örneklerinin kök ve kök boğazı kısımlarından elde edilen izolatlar, morfolojik ve moleküler yöntemlere göre D. seriata olarak tanımlanmıştır. Moleküler tanımlamada izolatların ITS (Internal Transcribed Spacer) ve TUB2 (β-tubulin) gen bölgeleri Real-Time PCR ile çoğaltılmış ve bu gen bölgelerinden nükleotid dizileri elde edilmiştir. Daha sonra MEGA 7 yazılımı kullanılarak ITS ve TUB2 dizileri hizalanmış ve kombine bir filogenetik ağaç çizilmiştir. Diplodia seriata izolatı