Abstract:
In this study, accumulation of H
2
O
2
, malondialdehyde (MDA) (as cold-induced oxidative
stress indicators), the transcript levels of
dehydrin
and
beta-glucosidase
genes (involved in
metabolic responses) was evaluated in chickpea cv.
Jam, using qRT-PCR during control, cold
acclimation (CA), cold stress
(CS), recovery, and freezing phases. Results showed
the
existence of wide range of genetic capacity in the
cultivar to increase cold tolerance when
environmental conditions change. Significant increa
se in H
2
O
2
and MDA content during CA
phase indicated that seedlings perceived cold signa
ling that resulted in remarkable increase in
the transcript levels of
dehydrin
and
beta-glucosidase
genes as part of defense responses of
plants. Balancing the expression of these genes and
oxidative stress indicators showed the
interplay between two major defense and injury path
ways. During freezing phase, the higher
transcript levels of these genes in acclimated plan
ts compared to non-acclimated plants showed
a more active role for plant cells. An incapability
of defense machine in non-acclimated plants
was a limiting factor determining the low potential
of chickpea plants to freezing phase. It was
suggested that adjustment and metabolic alterations
like
dehydrin
and
beta-glucosidase
genes,
especially after CA phase and, thereby, decrease in
oxidative stress indicators, could be a
reason for relative cold tolerance in chickpea.
Keywords:
Beta-glucosidase,
Chickpea,
Cold responses,
Dehydrin gene,
qRT-PCR.
