Abstract:
A laboratory experiment was set-up at the Agronomy lab of the Central
Laboratory, Sher-e-Bangla Agricultural University (SAU), Sher-e-Bangla
Nagar, Dhaka-1207 during 22 April to 15 June, 2018. The experiment was
undertaken to evaluate the effect of pre-sowing seed treatment with mannitol in
relation to drought tolerance and to optimize the priming time of the best priming
solution concentration on mungbean (Vigna radiata L.) (BARI Mung 6 and
Binamoog 5). The whole experiment was alienated into three experiments. In
first experiment, two mungbean varieties were primed in water and mannitol
(2%, 4%, 6%, and 8%) for 9 hours and dry seed used as control. The highest
germination percentage (96.66%), germination index (80.75) and energy of
emergence (98.00%) was were obtained from seeds primed in 4% mannitol for
Binamoog 5 and highest coefficient of velocity (22.46), shoot length (153.8 mm),
root length (92.98 mm), seedling dry weight (90.49 mg), vigor index (235.3),
water content (90.47%) and water retention capacity (20.70) were obtained from
seeds primed in 6% mannitol for BARI Mung 6. In second experiment, BARI
Mung 6 and Binamoog 5 was primed in under 6% and 4% mannitol solution and
distilled water respectively for 0, 3, 6, 9, 12 and 15 hours. 9 hours priming with
6% mannitol showed the best result in BARI Mung 6 and in Binamoog 5, 6 hours
priming with 4% mannitol stated the best results for inducing drought tolerance.
In the final experiment, seeds were primed with distilled water and 6% mannitol
with 9 hours for BARI Mung 6 and 4% mannitol with 6 hours for Binamoog 5;
dry seed used as control and were exposed to 0%, 5%, 10%, 15%, and 20%
Polyethylene Glycol (PEG) induced drought stress conditions in Petri dishes.
Priming with mannitol followed by water were more effective than the control
seed in inducing drought tolerance of mungbean cultivars owing to enhance
germination and growth parameters under drought stress condition. From the
results of the study, it was observed that 9 hours priming with 6% mannitol
showed the best result in BARI Mung 6 and in Binamoog 5, 4% mannitol
priming for 6 hours stated the best results in comparison to water primed seed
and non-primed seed.
