Download A Short Interval, Post Imbibition Exposure Method to Study the Effects of Hypergravity

A short interval, post imbibition exposure method to study the effects
of hypergravity
Pandit B. Vidyasagar and Sagar S. Jagtap
Biophysics Laboratory, Department of Physics, University of Pune, Pune- 411007, MH, INDIA.
Summary
reversible which shows that a molecular
Here we report a new experimental method
phenomenon is involved in it. Similar studies
namely, a short interval, post imbibition hyper
were also carried out on rice and mung bean.
gravity exposure to study the effects of hyper
Thus, a new experimental method to study the
gravity and reversibility of these effects. Studies
molecular mechanisms in plants is introduced
were carried out to study the effects of
where seeds are exposed to higher g values
hypergravity by exposing the seeds to different
(hypergravity) for short time interval and are
hypergravity conditions for 10 minutes and then
grown under normal gravitational (1 g) and
growing them under normal gravity for 5 days.
environmental conditions.
Results showed retardation of growth and
References:
chlorophyll content in hypergravity indicating that
Waldron, K. W., Brett, C. T. 1990. Effects of extreme
plants have “memory” of exposure to
acceleration on the germination, growth and cell
hypergravity. Interestingly, hypergravity effects
wall composition of pea epicotyls. J Exp Bot 41, 71are
reversible
which
shows
molecular
77.
mechanism is involved in it.
Introduction
Various environmental stimuli such as light,
water, temperature and gravity influence the
growth and development of plants. Hypergravity
stimuli (gravitational acceleration more than 1 g)
have been shown to decrease the growth rate of
1-6
shoots in various plants . Lignin formation and
cell wall polysaccharide content in cress
2
hypocotyls and hemicellulosic polysaccharides
3
in wheat coleoptiles increased in hypergravity.
Similar results have been obtained for maize
coleoptiles and mesocotyls when 3 days old 2025 mm long maize seedlings were exposed to
7
hypergravity i.e. 300 g for 6 hrs at 25°C in dark
and for azuki bean epicotyls when 5 days old
30-35 mm long azuki bean seedlings were
8
exposed to 300 g for 10 hrs at 25°C in dark . In
these studies seedlings were continuously
exposed to hypergravity using centrifugal
machine. But it is very difficult to maintain
seedlings to higher g values for such a long time
and also there is a possibility of vibration and
other stresses during such continuous exposure
to hypergravity which may also affect the plant
growth. Here we report the results of effects of a
short interval, post imbibition hypergravity
exposure on plant growth and chlorophyll
content and reversibility of these effects.
Results and Discussion
Results obtained show that a short interval, post
imbibition hypergravity exposure retards growth
and lowers chlorophyll content in wheat
seedlings. Interestingly, these effects are
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