Population Structure and Sexual Fertility of Colletotrichum gloeosporioides sensu lato from Citrus in Northern Iran

Abstract

Anthracnose caused by Colletotrichum gloeosporioides s. l. is one of the most important diseases of citrus in northern Iran. To study the g enetic structure of C. gloeosporioides s. l. from citrus spp., infected samples were collected from three ci trus cultivating regions of northern Iran, during the summer of 2009. Fifty one monoconidial isolates were used as the objective of REP- and BOX-PCR fingerprintings. Eight fingerprinting groups were observed in the constructed phenogram. The largest proportion (94.37%) of total genetic diversity (H t ) was attributed to diversity within populations (H s ). Estimates of Nei’s genetic similarity and distances exhibited the high level of similarity among three populations. The value of gene flow, N M = 8.4, indicates that there is low limitation to ge ne flow among these geographically distant populations , which make these groups genetically homogenous. The results indicate that the three geo graphic populations are not developing independently and can be part of a Mega- population. Forty three isolates were divided into 19 groups in the phenogram constructed by combination of morphological characteristics data. Estimation of correlation bet ween morphologic and rep-PCR matrixes indicated a weak and non-significant corre lation between morphology and rep- PCR haplotypes (r= 0.2, P= 0.992). Fifty one isolat es were examined to clarify their sexual behavior. Eight isolates were identified as homotha llic and 14 successful outcrosses were observed among self-sterile isolates. Keywords: Anthracnose, Diversity, Gene flow, Perithecium.