Molecular and morphological identification of fungal disease agent Trichothecium roseum developing secondarily to gray rot caused by Botrytis cinerea isolated from grapes in Turkey

Abstract

Aims: Identification of Trichothecium roseum infecting grapes first time in Turkey.Methods and Results: During the summer of 2020, white and pale pink stains were observed on grapes in the vineyards and on the harvested grapes in storages. These stains resembling powdery mildew on the grapes were observed on the clusters, mostly developing secondarily to gray rot caused by Botrytis cinerea. To determine of the causal agent of disease symptoms, some symptomatic clusters were collected both from the vineyards and storages located in Hassa district of Hatay province in Turkey. Two different methods were used to isolate the fungus from the symptomatic tissues. For molecular identification, ITS rDNA gene sequence were amplified using ITS1 and ITS4 primers. Spore suspension of the fungus was sprayed on detached vine organs such as leaf, bud, stem and cluster, and after 7 days diseases symptoms were observed resembling those in the orchard. ITS1/4 primer pairs produced about 700 bp band on the agarose gel. Based on the morphologic and molecular characteristics, the fungus was identified as Trichothecium roseum and it has been identified for the first time on grapes in Turkey with this study.Conclusions: Trichothecium roseum is present on grapes in Turkey and there is no difference in the incidence or prevalence of Trichothecium roseum in the vineyards in the cultivation areas of Hassa district of Turkey.Significance and Impact of the Study: Trichothecium roseum was detected for the first time on vineyards in Turkey with this study. This fungus does not cause significant economic damage directly, but it causes both economic and health problems due to the mycotoxins which are produced by the fungus.