New Horizons in Insect Science Towards Sustainable Pest Management

342 T. Venkatesan and S. K. Jalali

reducing egg hatch, which resulted in lesser boll

damage (Table 11 ).

Plots that received the combination of MI-

HTTS + insecticides recorded highest yield

14.8 q/ha compared to 12.4 q/ha in susceptible

strain + insecticides and 14.3 q/ha in farmers’

practice plots. Besides, significant reduction in

insecticide sprays was also observed in field-

collected population released plots.

Tomato

During 1st year field evaluation, egg parasitism

by Trichogramma in various plots before ini-

tiation of releases was very low ranging from

1.0–4.0 %. The post-treatment egg parasitism in

MIHTTS of T. chilonis plots was significantly

higher than egg parasitism by susceptible strain

plots. In general, in farmers’ practice plots egg

parasitism was least, even lesser than untreated

control (Table 12 ). The releases of T. chilonis

commenced with moth capture in pheromone

traps and coincided with period of egg laying

Table 11 Effect of field release of MIHTTS of T. chilonis on its efficacy against cotton bollworms and yield at Sirsa
(Haryana) during 2nd year trial
Treatments No. of larvae/
Plant

BOB GOB % boll damage Yield (q/ha)

MIHTTS of T. chilonis 0.3 2.7 18.3 3.5 14.8
Susceptible strain 0.9 4.2 10.0 4.8 12.4
Farmers’ practice 1.3 5.6 14.3 4.1 14.3
Untreated control 0.22 0.18 0.65 0.17 0.74
SEM. ( ± ) 0.48 0.43 1.82 0.39 1.52
LSD (0.05) 0.73 0.82 2.45 0.57 2.12
LSD (0.01) 32.4 8.43 8.56 8.37 7.48
BOB bad open bolls, GOB good open bolls

Table 12 Effect of field release of MIHTTS of T. chilonis on percent egg parasitism and larval population of H. armi-

gera on tomato in Malur (Karnataka) during 1st year trial

Treatments Egg parasitism (%) No. of larvae/Plant Fruit bored (%) Yield (q/ha)

MIHTRS of T. chilonis 80.0 1.5 0.78 495.0

Susceptible strain 13.3 4.8 4.05 407.1

Farmers’ practice 5.0 3.7 0.91 421.5

Untreated control 20.4 5.9 11.5 257.4

SEM. ( ± ) 3.3 0.66 0.77 1.35

LSD (0.05) 7.26 1.44 1.67 2.94

LSD (0.01) 10.18 2.02 2.34 4.12

CV (%) 17.75 26.36 28.12 0.54

Table 10 Effect of field release of MIHTTS of T. chilonis on its efficacy against cotton bollworms and yield at Sirsa

(Haryana) during 1st year trial

Treatments No. of larvae/Plant BOB GOB % boll damage Yield (q/ha)

MIHTTS of T. chilonis 0.5 2.4 15.7 2.2 15.0

Susceptible strain 0.8 3.7 11.0 3.5 12.6

Farmers’ practice 1.2 4.6 12.0 3.9 14.1

Untreated control 0.8 3.6 12.9 3.2 13.9

SEM. ( ± ) 0.12 0.13 0.55 0.17 0.54

LSD (0.05) 0.27 0.30 1.27 0.39 1.25

LSD (0.01) 0.39 0.43 1.84 0.57 1.83

CV (%) 21.9 5.67 6.74 8.37 6.19