Genetic diversity of Botrytis cinerea isolates in different plant hosts and localities using ISSR molecular markers

Botrytis cinerea has a wide host range, the possibility of hiding plant infection from the initial stages, and causing severe damage (even up to 100%) to the host.  Due to the chance of growth and activity of the pathogen in field, greenhouse, in laboratory, and even in cold storage conditions, its importance is increasing. The presence of pathogen in seedlings, mature plants, ripe fruits, and even storage conditions in different parts of Iran and its importance, we decided to investigate the genetic diversity of the isolates using the ISSR marker. For this purpose, 21 isolates including 16 isolates from the collection of the University of Tehran (isolated from seedling and leaf of cauliflower, grizzly lettuce, needled lettuce, purple basil, onion, tomato, strawberry and pomegranate) and five isolates collected from two strawberry greenhouses in Alborz province, were used. Ten ISSR primers were used to determine the genetic diversity. Analyzing the results by NTSYS software version 2.02e (based on SM and UPGMA clustering method) showed that the isolates fall into four fingerprinting groups. It was also observed that the resulting bands have 100% polymorphism (93.33% in one case). The calculated cophenetic coefficient for the data (0.89) confirmed the accuracy of the obtained dendrogram. Evidence suggests that there is high genetic diversity in B. cinerea isolates and also there is no relationship between host and geographical region.