Fungal trunk pathogens of Sultana Seedless vineyards in Aegean region of Turkey

Abstract

In recent years, grapevine trunk diseases have become a problem in Sultana Seedless vineyards of Manisa and Izmir provinces (Aegean Region, Turkey). A field survey was conducted in 2013 in these provinces (in 8 cities and 80 vineyards) to determine disease incidence, fungal species associated with grapevine trunk diseases and pathogenicity.  Symptomatic vines were grouped by two different grapevine trunk disease symptoms: (1) typical tiger-striped leaves, (2) dead arm, shoot decline or apoplexy. Over 80% of vineyards in these areas were positive for at least one characteristic trunk disease symptom. Incidence of tiger-stripe symptom ranged from 2.9-15% and incidence of apoplexy ranged from 0–4.2%. Eight fungal species in five fungal families were identified from declining grapevines based on morphological and molecular (ITS, β-tubulin and EF1-α) studies including, Botryosphaeria dothidea, Diplodia seriata, Lasiodiplodia theobromae, Neofusicoccum parvum, Diaporthe ampelina, Phaeomoniella chlamydospora, Togninia minima and Fomitiporia mediterranea. Overall, D. ampelina was the most frequently recovered fungus from symptomatic grapevine tissues followed by botryosphaeriaceous fungi, P. chlamydospora, F. mediterranea and T. minima. Pathogenicity tests confirmed all eight fungi as pathogens of grapevine in these regions with N. parvum being the most virulent among the fungi tested.