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.