Other Lepidopteran pests of minor importance for potato crop:
4. Bihar hairy caterpillar: Spilosoma obliqua Walker
(Lepidoptera: Noctuidae)
5. Army worms: Mythimna separata Walker
(Lepidoptera: Noctuidae)
6. Brinjal Shoot and Fruit borer: Leucinodes orbonalis
Guen. (Lepidoptera: Noctuidae)
Life cycle
of
Lepidopterans:
•
Each
female may lay 300 eggs in clusters covered with brown hair.
•
Eggs hatch in 3-5 days.
•
Larvae become full fed in
15-30 days
•
Pupal period is 7-15 days.
•
Adult longevity is 7-10 days
•
Total life cycle is
completed in 32-60 days.
•
8 overlapping generations in
a year.
•
Most congenial temperature
range for lepidopteran development is 18-30˚C.
Figure: Life cycle of lepidopterans
Management of caterpillars:
-
Clean cultivation to expose the larvae
to natural enemies, deep summer ploughing to expose the pupae to the sunlight
and natural enemies.
-
Hand picking and destruction of egg
masses and early gregarious instars. African marigold as trap crop for H.
armigera.
-
Installation of pheromone traps (5
traps/ha) for monitoring and mass trapping of adult moths.
-
Spray of Helicoverpa nuclear
polyhedrosis virus (HaNPV) or Spodoptera nuclear polyhedrosis virus
SlNPV @ 250 larval equivalent/ha at weekly intervals against Helicoverpa
and Spodoptera.
-
Application of Bt formulation @ 3gm/litre
of water.
-
Release of egg parasitoid,
Trichogramma brasiliensis @ 250000 /ha during high adult activity.
-
Spray of neem seed kernel extract (NSKE)
@ 4.0 % at early growth stage of the crop.
-
Need based spray of Cypermethrin 25EC @
0.30ml or Deltamethrin 28EC @ 0.1ml/lit of water when 2 larvae are seen per 10
plants.
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