ABSTRACT
Irradiated seeds of Phaseolus vulgaris cv. Rajmah using
Synchrotron X Ray Beam (BL-07) in RRCAT, Indore at doses of 1, 10 and 20 Gy
were used to raise the seedling and the effects on growth and biochemical
constituents in 4 - 8 days, old seedlings were analyzed. The seed irradiation effect on seedling
development up to about 4 - 5 days, % germination, seedling length and seedling vigor are
significantly decreased at 10 and 20 Gy doses with strong -ve correlation.
Other parameters, like relative water content, electrical conductivity and acid phosphatase activity are also decreased.
Decrease in various biochemical constituents, like, protein and proline has shown significant reduction at 10 and 20 Gy and
phenol at 1 - 20 Gy. However, peroxidase activity is increased at 1 and 10 Gy. Amongst
the antioxidant enzymes, only superoxide dismutase activity has shown significant increase at 10 and 20 Gy. For seed irradiation
(1 and 10 Gy) effect on seedling development up to 8
days involving transfer to hydroponic
culture after 4 days, in shoot tissue, decrease in nitrate reductase activity
and pigment content is observed, while nitrate reductase activity in root tissue
is increased. The results demonstrate adverse effects on growth as well as
biochemical constituents along with increased antioxidant effect in bean
seedlings with irradiation of seeds at high dose of synchrotron X radiations.
Also the nitrate assimilation and photosynthetic activity are reduced in shoot
tissue with seed irradiation, however, increased nitrate reductase activity in
roots suggests the involvement of NO signaling.