Abstract:
Abiotic stress has become an alarming issue for plants survivable due to the constant
changes in the environment. Stresses such as drought, salt, waterlogging and heavy
metals largely influences plant growth and development that finally reduces crop
productivity. Focusing this issue, two individual experiment, germination trial
(Experiment-I) and pot experiment (Experiment-II) were carried out at Sher-e-Bangla
Agricultural University, during the kharif-1 season of 2019 to investigate the responses
of tossa jute (Corchorus olitorius) cv. O-9897 under different abiotic stresses.
Experiment-I and Experiment-II were designed in completely randomized design
(CRD) and randomized complete block design (RCBD), respectively. In Experiment-I
seeds were exposed in two doses of salt (75 and 100 mM NaCl) and Cd stress (0.5 and
1 mM CdCl
2
). Germination parameters were affected by salt stress where seedling
parameters were highly damaged by Cd stress. At 15th day after sowing (DAS) plants
were exposed to salt, cadmium (Cd), waterlogging and water deficit condition for
various duration in Experiment-II. Two doses of NaCl (200 and 400 mM) were applied
to impose salt stress, while two doses of CdCl
2
(2 and 4 mM) were applied for Cd
stress. Among two waterlogging treatments, 5 days of waterlogged condition was
imposed at 15 and 30 DAS in first one and in second one 20 days of waterlogged
condition was imposed. For water deficit, water was withheld from soil for the duration
of 10 and 15 days. Morphological parameters like plant height, relative water content,
above ground fresh and dry weight, SPAD value, leaf area and stem diameter were
decreased upon exposure to salt, water deficit, waterlogging and Cd. These treatments
were also resulted in oxidative stress which was evident by the increased levels of lipid
peroxidation (MDA), H
2
O
2
and electrolyte leakage and decrease in catalase enzyme
activity. Results also revealed that waterlogging and drought stress drastically affected
plants morpho-physiology, whereas C. olitorius could tolerate moderate level of salt
(i.e. 200 mM NaCl) and Cd (i.e. 2 mM CdCl
2
). Considering this fact, it may be
concluded that tossa jute become susceptible towards either duration of waterlogging
and drought stress, salt stress more than 200 mM NaCl and Cd stress, more than 2 mM
CdCl
2
.
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
