Seyedeh Masoomeh Zamani - Ph. D. in Plant Pathology, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO),Tehran, Iran
Shideh Mojerlou - Assistant Prof., Department of Horticulture and Plant Protection, College of Agriculture, Shahrood University of Technology, Shahrood, Iran
Abbas Ghamari Zare - Associate Prof., Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO),Tehran, Iran,

Boxwood blight disease, caused by Calonectria pseudonaviculata (syn. Cylindrocladium pseudonaviculata, C. buxicola) is responsible for considerable damages on Buxus spp. in nurseries, gardens and wild boxwood populations in Iran and the world. Knowledge of the population structure and genetic diversity of the fungal pathogen can help to implement effective disease management strategies. In this study rep- (REP and ERIC) PCR genotyping were used to assess genetic heterogeneity in a collection of 21 representative isolates of a total 52 Iranian isolates of C. pseudonaviculata, which showed the highest pathogenic and morphological diversity, originating from 12 forest areas in three Northern provinces of Iran. Cluster analysis using UPGMA method and Jaccard s coefficient showed that, although results were comparable, REP fingerprints discriminated the isolates better. The rep-PCR genotyping showed that isolates from different geographical regions produced identical rep-profiles indicating limited genetic diversity. The concatenated dendrogram of REP- and ERIC-PCR fingerprints clustered the isolates into four major groups. In each group, majority of the isolates from Mazandaran, Gilan and Golestan province exhibited similarities ranging from 95% to 99%. Similarity of fingerprints among isolates from different geographical regions revealed existence of a limited number of clonal groups of C. pseudonaviculata in Iran, and suggesting a potential epidemiological link. Overall, these data indicated a low level of genetic diversity in the Iranian C. pseudonaviculata isolates population similar to that reported in other countries, so it seems that in the disease control, the use of resistant cultivars is one.

Calonectria pseudonaviculata, Iranian isolates, rep-PCR, Genotyping.