Biomedical Engineering Reference
In-Depth Information
Figure 1.
The disease cycle of Verticillium wilt as illustrated using a GFP-tagged strain
of
V. dahliae.
(Color image of this fi gure appears in the color plate section at the end of the topic.)
The genus
Verticillium
encompasses mainly three phytopathogenic
species,
V. dahliae
,
V. albo-atrum
and
V. longisporum
. Conventionally, these
three
Verticillium
species are mainly identifi ed based on the resting structures
they produce.
Verticillium dahliae
and
V. longisporum
produce microsclerotia,
a darkly melanized survival structure, but the latter species also produces
elongated conidia. In contrast,
V. albo-atrum
produces melanized hyphae as
a survival structure (Klosterman et al. 2009). Furthermore, two races have
been described in
V. dahliae
and resistance for race 1 is available in both
lettuce and tomato, but sources of resistance against race 2 isolates have
remained elusive (Vallad et al. 2006, Maruthachalam et al. 2010, Hayes et
al. 2011).
So far, only a few pathogenicity genes have been characterized in
this fungus and additional characterization of the genes required for
pathogenicity is very essential to understanding pathogenicity mechanisms
and to develop novel disease management methods for Verticillium wilt
(Dobinson et al. 2004, Klimes et al. 2006, Gao et al. 2010, Tzima et al. 2010,
Maruthachalam et al. 2011a). Recently, genomes of
V. dahliae
(both race 1
