Abstract:
The experiment was carried out at Sher-e-Bangla Agricultural Uni versity, Dhaka1207,
Bangladesh,
during
the
period of October, 2017 to March, 2018 and November
2018 to March 2019 to study combini ng ability and heterosis in intraspecific hybrids
of some tomato genotypes. With eight tomato genotypes viz. G1
(SL-006), G2
(SL007),
G3
(SL-008), G4
(SL-009), G5
(SL-0010), G6 (SL-0011), G7 (SL-0012) and G8
(SL-0013) the experimental field was organi zed i n Randomi zed Complete Block
Design (RCBD) in three replications. In this study nineteen characters includi ng both
agromorphogenic, nutritional and physiological were taken under consideration. High
general combi ning ability observed in parents G1, G3, G5 and G6 for one or more
yield contributing traits. Characters like days to 1
st
and 50% flowering, number of
cluster per plant, fruit per cluster, fruit per plant, fruit wt, fruit area, relati ve water
content, fruit pH and yield were governed by non-additi ve gene action. The maximum
SCA effects was observed i n t he cross combinations G2×G1for higher yield and
lowest in G2×G7 for days to first and 50% flowering and G2×G1 for early mat urity.
Highest desirable significant heterobeltiosis for yield related characters was expressed
by t he F
hybrids G2×G6 (Plant hei ght), G3×G6 (branch number), G2×G8 (cluster
number), G4×G3 (average fruit in one cluster), G2×G8 (fruit per plant), G1×G6 (fruit
wt .), G5×G2 (fruit area) whereas, negati ve heterosis was hi ghest i n the crosses G3×G5
(1
st
1
flowering), G3×G5 (50% flowering) and G1×G8 (maturity days). Most of the
chemical traits showed significant heterosis. Thus, these three combinations could be
feasible for further selection to obtain high yielding, short duration and longer shelf
life.
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
