Neoscytalidium dimidiatum (Ascomycota, Botryosphaeriaceae) همراه با سرخشکیدگی و شانکر دوده ای گیاهان زینتی در شهر یزد

Botryosphaeriaceae species have a global distribution and are able to infect a wide range of plant hosts as saprobes, parasites, and endophytes. In Iran as well as other counties, various members of Botryosphaeriaceae family have been reported to cause trunk diseases on fruit trees and ornamental plants. During a survey conducted on ornamental plants in Karizboom Cultural, Recreational and Tourism Complex (Yazd County, Yazd Province) disease symptoms including dieback and sooty canker were observed and recorded on ash, black and mushroom locust, common and field elm, eldarica pine, oleander, Russian olive, and white mulberry. Samples were collected from affected plants and taken to the laboratory at the Shahid Bahonar University of Kerman for further studies. Fungal isolations were made from symptomatic plant tissues. Small pieces (4  4  4 mm) of diseased tissues were surface sterilizing in 0.5% sodium hypochlorite (NaOCl) for 90 sec., rinsing thrice in sterile water and then plating onto potato dextrose agar (PDA) medium. All Petri dishes were incubated at 25°C and emerging fungal colonies were transferred to new PDA media. In this study 64 isolates of a Neoscytalidium sp. were obtained from infected wood plant tissues. Hyphal tip cultures were established for all recovered isolates for further studies. Representative isolates recovered from each plant host were selected for molecular identification. For these isolates, the internal transcribed spacer regions 1 and 2 (ITS) and a part of translation elongation factor 1-a (tef-1α) were amplified and sequenced using primer sets of ITS1/ITS4 and EF1–728F/EF1–986R, respectively. Based on morphological characteristics and molecular data all fungal isolates were identified as Neoscytalidium dimidiatum. The current study shows that N. dimidiatum is associated with dieback and sooty canker symptoms on a range of ornamental plants in city landscapes. Outcomes of this research can improve the importance of the Botryosphaeriaceae species in trunk diseases of ornamental trees in the green spaces.