For Clean, Smart and Profitable Farming.
Pest Management
Pests of Cucurbits
Several pests are found to damage these crops, important among them are pumpkin beetles, fruit flies, epilachna beetle, mites, jassids, cutworms and leaf eating caterpillars. The extend of damage caused by these pests, however, varies in different crop e.g. fruit fly is the most serious pest of "Tondali" while epilachna beetle is the most destructive to "Karli".
1. Fruit fly
Dacus ciliatus L.Dacus cucurbitae C. Dacus zonatus S.
Family: -Trypetidae
Order: - Diptera
- Economic Importance
These are cosmopolitan species causing huge annual losses to several fruit and vegetable crops. Two species of fruit flies, the Ethiopian fruit fly D. ciliatus L. and melon fly, B.cucurbitae C are the predominant species damaging cucurbits and melons. The other species D.zonatus S. has also been reported to damage long melon. These species breed almost throughout the year except winter during which they hibernate as pupae or adults. During rainy season, the activity of melon fly is at the peak while heavy rains stop breeding of Ethiopian fruit fly.
- Marks of Identifications
The adult fly resembles common housefly but has conical yellowish brown abdomen and transparent wings having grey sports and bands. It measures 5 mm long. The maggot is a small, dirty white, and leg- less larva, measuring about 12 mm in length and tapering it one end.
- Nature of damage
Among the various species, D.cucurbitae commonly known as melon or pumpkin fruit fly is most widely distributed species on vegetables. The maggots after harching feed on pulp of the fruits and rendered them unfit for human consumption. The fly is active in hot and hibernates as pupae or adults during the cold months.
- Life history
Long white eggs are laid by the female just under the skin of the fruits. The incubation period is 3-5 days. The larval period varies from 2-3 weeks. Full fed maggots mostly pupate in soil. The adults emerge after 8-10 days.
- Host plants
Gourds, melon, tondali, guava, mango, ber and other fruits
- Control measures
- Clean cultivation- Removal and destruction of fallen fruits and infested fruits daily to minimize the pest intensity.
- Spraying with 0.2% carbaryl is also found effective.
- Deep ploughing to expose hibernating stages, Application of spray baits and use of chemical traps are also found useful in reducing the intensity of infestation (see mango fruit fly control also) and
- Five spraying with 0.05% Malathion at 10 days interval starting from flowering are reported to reduce the intensity of infestation.
- Use of pheromone traps for monitoring pest population.
2. Pumpkin beetle
Red pumpkin beetle - Raphidopalpa foveicollis L.
Black pumpkin bettle – A.intermedia J.
Family: - Chrysomelidae:
Ceratia cincta F.
Family: - Coleoptera
- Economic Importance
Of the six species noticed, in the State of Maharashtra, the commonly known red pumpkin beetle is the most destructive, next in order of importance are black pumpkin beetle. Maximum damage in caused by overwintering beetles during March to May, reaching its peak in middle of April.
- Marks of Identification
Adult beetles measures 5.7-7.25 mm in length. Elytra of red pumpkin beetle R. foveicollis is pale orange yellow to deep pale brown while in case of black pumpkin beetle. R. intermedia, it is black and C.cincta it is yellow. Grubs are slender, elongate, pale creamy yellows with brown head and legs. Full grown grub measures 12 mm long.
- Nature of damage
Adult beetles are mainly responsible for the damage of the plant above ground, attacking on the leaves, flowers and fruits. Making holes and causing death or retardation of growth. In case of heavy infestation, re-sowing is required to be done. Larvae live in the soil and feed on the roots and stem of the plant. Fruits and leaves are also damaged when they come in contact with soil.
- Life history
Eggs are laid in wet soil to a depth 25 mm near the plant. A single female lays 150 to 200 eggs. They hatch in 5-27 days depending on temperature and moisture content of the soil. The grubs become full-grown within 12 to 34 days and pupate in soil. Pupal stage lasts for about 15-35 days. Adults live for 20-197 days. Thus, the life cycle is completed in 52 to 270 days. The maximum activity of the pest is observed during hot weather and reaches its peak during the middle of April.
- Host plants
All cucurbits damaged by this pest however, bottle gourd, red pumpkin cucumbers are heavily damaged by Red pumpkin beetle but smooth gourd and bitter gourd are relatively less damaged.
- Control measures
1. Preventing measures like
burning of old creapers, ploughing and harrowing of field after harvest of the crops are
recommended for the destruction of adult, grubs and pupae.
2. Spraying with 0.05%
Malathion gives satisfactory control of the pest .
3. Dusting with 5% Malathion @ 10
kg/ha. In addition, jassids, mites and leaf eating caterpillars are also recorded as minor
pests.
4. Collection and
destruction of beetles in early stage of infestation.
Note
Some of the modern
synthetic insecticides DDT, BHC, Chlordane-toxaphene, heptachlor etc. belonging to
chlorinated hydrocarbon group are reported to be phyrotoxic to cucurbits.