Abstract:
A field experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka during
the period from November 2020 to April 2021 in Rabi season, to evaluate some popular
mustard varieties against aphid and sawfly attack under field condition. The experimental
treatments were consisted of two factors, and followed by randomized complete block
design with three replications. Factor A. mustard varieties (3) viz; V
1
= BARI sharisha-1,
V
2
= BARI sharisha-9 and V
3
= BARI sharisha-14 and Factor B: different biorational
pesticides (3) viz; P
0
= untreated (Control), P
1
= Confidor 70 WG (imidacloprid) @ 0.2 g/L
of water, and P
2
= Tracer 45 SC (spinosad) @ 0.4 ml/L of water. The result of present
studies related to the incidence of insect pests and its natural enemies revealed that the
populations of mustard sawfly, mustard aphid and other insect-pests were ranged between
0.33 to 2.33 (larvae/plant), 0.33 to 55.33 (aphids/10 cm central twig/plant), 0.33 to 2.67
(insect-pests/plant), respectively. The population of Coccnella spp., syrphid fly, spider and
other predators was ranged between 0.33 to 4.00 (larvae and adults/plant), 0.33 to 3.67
(larvae/plant), 1.00 to 2.67 (spiders/plant) and 0.33 to 2.33 (predators/plant), respectively.
The major pest i.e. mustard aphid showed a significant positive correlation with
coccinellids, spiders and others. However, a non-significant correlation of mustard sawfly
appeared with coccinellids, Syrphid fly, spiders and others. The population of mustard
sawfly and aphid reduced due to the application of biorationals pesticide and different
mustard varieties treatments. The highest seed yield plot
-1
(0.36 kg) was observed in V
3
(BARI sharisha-14) treatment. Among different biorational pesticide, application of
Confidor 70 WG (imidacloprid) @ 0.2 g/L of water recorded the highest the seed yield
plot
-1
(0.51 kg). Among different treatment combination, V
3
P
1
treatment combination
performed best, recorded higher seed yield plot
-1
(1.57 ton/ha) and was found superior
overall other varieties and botanical to significantly minimum insect-pests incidence, high
reduction percent and higher seed yield production of mustard comparable to other
treatment combinations.
Description:
A Thesis
Submitted to the Institute of Seed Technology,
Sher-e-Bangla Agricultural University, Dhaka,
In Partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE
IN
SEED TECHNOLOGY