Abstract:
Maize (Zea mays L.)
constitutes one of the most important crops
worldwide with multi-billion dollar annual
revenue. The plant is however a good
substrate for growth, development and
activity of filamentous fungi. A large
number of fungal species causes spoilage
and accumulation of mycotoxins. Plants
restrict the hyphal growth by producing
pathogenesis related proteins. So far 17
groups of such proteins are identified. PR-5
group comprises of the thaumatin-like
proteins (TLPs), which have diverse modes
of actions and act at various stages of fungal
attack. Zeamatin-like protein (ZLP) is a
member of TLPs, which is basically
localized in seeds with enhanced expression
during physiological growth and cellular
differentiation. However a basal quantity is
found in the leaves of many crop plants.
Here we report the response of maize plant
tissues against A. niger inoculation by
measuring the variation in expression
profile of a zeamatin-like gene.
Conventional PCR coupled with RT-qPCR
identifies a significant change in the
expression magnitude of ZLP in pre- and
post-inoculated plant samples. SDS-PAGE,
followed by antimicrobial activities against
A. niger, E.coli, P. aeruginosa, B. cereus,
S. aureus and S. typhimurium, however, do
not register a direct relationship with
enhancement in gene expression. It is in line
with the fact that response to pathogenesis
in plants is a multigenic activity involving a
series of responsible/induced genes. The
assay developed is useful in primary sorting
out of the maize hybrids with respect to
their resistance against Aspergillus spp.,
especially in areas with high rate of
incidence of fungal pathogenesis.