ROLE OF PHYTOHORMONES IN MITIGATING WATERLOGGING STRESS IN SOYBEAN
Date
2020
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
DEPARTMENT OF AGRONOMY
Abstract
Waterlogging is a devastating environmental stress for soybean. A pot experiment
was conducted at Department of Agronomy, Sher-e-Bangla Agricultural University,
Dhaka, Bangladesh during kharif-II season from August to November, 2019 to find
out the time-dependent responses of morpho-physiological, anatomical and
biochemical attributes of soybean (Glycine max) to waterlogging stress and the role of
foliar application of phytohormones in mitigating the adverse effects of waterlogging
condition. The experiment was conducted following completely randomized design
(CRD) with three replications consisted of 12 treatments as T
1
: control, T
: 0.5 mM
salicylic acid (SA), T
3
: 0.1 mM kinetin (KN), T
4
2
: waterlogged for 3 days, T
:
waterlogged for 3 days + 0.5 mM SA, T
waterlogged for 6 days, T
for 6 days + 0.1 mM KN, T
8
6
: waterlogged for 3 days + 0.1 mM KN, T
: waterlogged for 6 days + 0.5 mM SA , T
10
: waterlogged for 9 days, T
: waterlogged for 9 days +
0.5 mM SA, T
12
11
: waterlogged for 9 days + 0.1 mM KN. Plants waterlogged for 3 days
showed fewer damaging effects than 6 and 9 days of waterlogging. Leaf number,
branch number, shoot length, root length, fresh weight and dry weight of 3 days
waterlogged plants were higher than 6 and 9 days of waterlogging. Due to the
exogenous application of SA and KN, the number of leaves, the number of branches,
shoot length, root length, adventitious root were significantly increased. The number
of pods per plant, seed yield and 1000-seed weight were higher due to exogenous
application of salicylic acid and kinetin than waterlogging condition. Proline (Pro),
malondealdehyde (MDA), H
2
O
and electrolyte leakage (EL) increased under the
waterlogging condition, which indicates higher oxidative stress. However, exogenous
application of SA and KN significantly enhanced plant morpho-physiological and
anatomical features and decreased Pro, MDA, H
2
2
O
content than the waterlogged
plants without phytohormone supplementation. Thus, the study indicates that the
foliar spray of SA and KN is an effective approach in improving the growth and
reproductive stage against waterlogged conditions.
Description
A Thesis
Submitted to the Department of Agronomy, Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka in partial
fulfillment of the requirement for the degree of
MASTER OF SCIENCE (MS)
IN
AGRONOMY
Keywords
ROLE OF PHYTOHORMONES, MITIGATING WATERLOGGING, SOYBEAN