New Horizons in Insect Science Towards Sustainable Pest Management

Sustainable Management of Tea Mosquito Bug Helopeltis antonii Signoret ... 395

tal stages. These findings are in agreement with
Sundararaju ( 2004 ).
The C to B ratio indicated that monocroto-
phos (0.05 %)—λ-cyhalothrin (0.005 %)—carba-
ryl (0.10 %) treated trees recorded higher net gain
1:17.03 (Table 5 ). Among the botanicals PSKE

(2 %) registered higher C to B ratio of 1:7.0.

Lower C to B ratio in botanicals and entomo-

pathogen may be due to their low effectiveness

in suppressing the pest leading to high percent-

age damage, as also reported by Thirumalaraju

et al. ( 2002 ). AQ3

Table 4 Effect of botanicals and insecticides against tea mosquito bug in field (pooled)
Treatments TMB damage (%)
New flush Panicle Nut and fruits
30 DAT 30 DAT 30 DAT
Pongamia oil–pongamia oil–pongamia oil 9.64 (18.12) 15.13 (22.85) 2.56 (9.16)
PSKE–PSKE–PSKE 7.50 (15.82) 12.13 (20.35) 1.90 (7.98)
Neem oil–neem oil–neem oil 17.07 (24.34) 21.42 (27.54) 5.46 (13.50)
NSKE–NSKE–NSKE 15.40 (23.08) 19.20 (25.98) 3.50 (10.66)
Beauveria bassiana–Beauveria bassiana–Beauve-
ria bassiana

20.22 (26.73) 24.73 (29.82) 5.98 (13.75)

Monocrotophos–λ-cyhalothrin–carbaryl 5.00 (12.87) 7.0 (15.30) 0.60 (4.36)
PSKE–λ cyhalothrin–carbaryl 6.61(14.82) 8.30 (16.72) 0.98 (5.63)
Beauveria bassiana–λ-cyhalothrin–carbaryl 7.53 (15.92) 7.56 (15.95) 0.76 (5.01)
NSKE–λ cyhalothrin–carbaryl 19.10 (25.91) 12.40 (20.55) 1.75 (7.18)
Monocrotophos–endosulfan–carbaryl 6.12 (14.29) 17.92 (25.01) 1.06 (5.87)
Control 22.67 (28.43) 27.92 (31.88) 7.87 (16.28)
CV 4.77 4.71 13.56
CD (0.05) 1.63 1.84 2.09
Values given in the parentheses are Arc sine percentage
DAT days after treatment

Table 5 Nut yield and economics for the treatments evaluated against tea mosquito bug in field
Treatments Nut yield (kg/tree)
treatments (`)

Cost of control

(`/ha)

Net returns over Benefit over

control (`)

C:B

Pongamia oil–pongamia
oil–pongamia oil

398.72 1200 18,736 4486 01:03.7

PSKE–PSKE–PSKE 477.04 1200 22,652 8402 01:07.0
Neem oil–neem oil–
neem oil

393.97 1850 17,849 3599 01:01.9

NSKE–NSKE–NSKE 439.07 1570 20,384 6134 01:03.9
Beauveria bassiana–
Beauveria bassiana–
Beauveria bassiana

309.72 1500 13,986 − 264 01:00.0

Monocrotophos–λ-
cyhalothrin–carbaryl

1106.57 2278 53,048 38,798 01:17.0

PSKE–λ
cyhalothrin–carbaryl

879.91 2278 41,718 27,468 01:12.1

Beauveria bassiana–λ-
cyhalothrin–carbaryl

684.71 1913 32,323 18073 01:09.4

NSKE–λ
cyhalothrin–carbaryl

510.86 1913 23,630 9380 01:04.9

Monocrotophos–endosul-
fan–carbaryl

488.31 2013 22,403 8148 01:04.0

Control 285 – 14,250 – –
Cost of raw cashew nut at the rate of ` 50/kg, the cost of treatments include cost of insecticides and labour