Abstract:
This study was conducted to investigate the genotype and stress interaction under
salinity and drought condition. The experiments were conducted in net house of
Department of Genetics and Plant Breeding, Sher-e-Bangla Agricultural University
from November 2018 to March 2019. Two independent experiments were conducted
with eight tomato genotypes collected from Department of Genetics and Plant
Breeding, Sher-e-Bangla Agricultural University. The genotypes were SL 021 (G
),
SL 022 (G
2
), SL 023 (G
3
), SL 024 (G
XVII
4
), SL 025 (G
5
), SL 026 (G
6
), SL 027 (G
) and
BARI tomato 11 (G
8
). Four salinity treatments viz. T
1
(control), T
(4 dS/m, mild
salinity), T
3
(8 dS/m, moderate salinity), T
(12 dS/m, severe salinity) and four drought
treatments viz. T
1
(control), T
2
4
(10 days withhold of water, mild drought), T
(20 days
withhold of water, moderate drought), T
(30 days withhold of water, severe drought)
were applied to the genotypes. Completely Randomized Design (CRD) with three
replications was followed in both experiments. Genotypes, salinity and drought
influenced singly and in interaction on agromorphogenic, physiological and nutritional
traits of tomato. Salinity treatment affected almost all traits of tomato negatively
except days to first fruit setting, days to maturity, dry matter content, Na+ uptake, Brix
content, titrable acidity and vitamin C content. Drought treatment interacted negatively
with all traits except days to first flowering, days to fruit setting, days to maturity,
proline content, etc. Early flowering (22.67 DAT) and early maturity (65 DAT) was
found in G
8
4
at moderate and severe salinity respectively. G
showed higher number of
cluster per plant, number of flower per cluster, number of fruit per cluster and number
of fruit per plant in both mild to moderate salinity and drought treatment. G
8
showed
higher average fruit weight and higher yield per plant in both mild to moderate salinity
and drought treatments. G
5
showed lower Na
+
uptake and higher K
+
uptake in severe
saline treatment and higher Membrane stability index at moderate drought treatments.
G
also showed higher increase of proline and vitamin C content with the increase of
drought treatment. From the research findings, G
5
could be suggested for early
flowering, early fruit setting, early maturity, higher dry matter content and highest
lycopene content at mild to moderate saline prone area. G
8
could be suggested for
higher number of clusters per plant, fruits per cluster and higher number of fruits per
plant for moderate saline and drought prone area. G
4
8
could be suggested for higher
fruit weight, higher yield per plant for mild to moderate drought and saline area. G
could be considered for the cultivation at mild to moderate saline condition for its
lower Na
+
uptake, higher K
+
uptake and higher vitamin C content. These genotypes
viz. G
4
, G
5
and G
could also be utilized as parental material for future hybridization
program for these specific traits at specific stress prone area of Bangladesh.
Description:
A Thesis
submitted to the Faculty of Agriculture
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE
IN
GENETICS AND PLANT BREEDING
SEMESTER: JANUARY-JUNE, 2019