Abstract:
An experiment was conducted at the Laboratory of Plant Stress Responses, Faculty of
Agriculture, Kagawa University, Japan to investigate the morpho-physiological and
biochemical responses of four lentil (Lens culinaris Medik.) cultivars viz. BARI Lentil1,
BARI
Lentil-2,
BARI
Lentil-5
and
BARI
Lentil-6
under
arsenic
(As)
stress.
Sevenday-old
seedlings
grown
in
hydroponic
culture
were
treated
with
different
levels
of
As
(0
µM,
80
µM,
160
µM,
320
µM
as
Na
2
HAsO
4
.7H
O) for four days. Arsenic treatments
reduced plant biomass and water content. Arsenic induced oxidative stress in lentil
2
through the overproduction of reactive oxygen species (ROS) which is indicated by
higher malondialdehyde (MDA), other aldehyde, electrolyte leakage (EL) and
hydrogen peroxide (H
2
O
) contents. Plant tried to cope up oxidative stress by
antioxidant defense mechanisms depending on the cultivars and As doses. Dry weight,
2
fresh weight, shoot length, water content, chlorophyll content, carotenoid content,
ascorbate were higher in BARI Lentil-1, BARI Lentil-2 compared to BARI Lentil-5,
BARI Lentil-6 at 320 µM As concentration with concomitant reduction in lipid
peroxidation (MDA content), other aldehyde, EL, proline, H
2
O
content and
translocation factor (TF). Activities of antioxidant enzymes-catalase (CAT),
dehydroascorbate reductase (DHAR), glutathione peroxidase (GPX) were decreased
while monodehydroascorbate reductase (MDHAR), glutathione reductase (GR),
superoxide dismutase (SOD) activity were increased in BARI Lentil-5, BARI Lentil-6
compared to BARI Lentil-1, BARI Lentil-2. Considering the morpho-physiological
parameters and antioxidant metabolism, BARI Lentil-1 and BARI Lentil-2 could be
recommended as relatively As tolerant over BARI Lentil-5, BARI Lentil-6.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfilment of the requirements
for the degree of
MASTER OF SCIENCE (MS)
IN
AGRONOMY
