• Pests:


          • The most common insect problems of pumpkins include cucumber beetles, squash bugs and squash vine borers. Control of squash bugs and vine borers should start when pumpkin vines begin to run and should continue on a regular basis

          • Squash bug (Anasa tristis):


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          • Squash bugs damage plants by removing sap, causing leaves to wilt and collapse. Young plants and infested leaves on older plants may be killed.


          • Control
            Cultural

            :

          • After harvest is complete, deep tillage or removal of crop residue will help to delay and/or reduce infestation the next cropping cycle.


          • Chemical

            :

          • Timing is the key to successful squash bug control. Insecticide sprays should target adults and small nymphs when the plants are small. It is much more difficult to control large numbers of older nymphs and adults when the plant canopy is dense. Treat with a recommended insecticide if adults are causing seedlings to wilt.
            Squash bugs may begin to appear in pumpkin fields about the same time vines begin to run. Monitor for squash bug egg masses from pre-bloom through early flowering. Treat when egg mass numbers exceed an average of one per plant. It is advisable to apply insecticides to control the nymphs when they are young.

          •  

          •  

          • Squash Vine Borer (Melitia cucurbitae):


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          •  

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          • Symptoms appear when a long runner or an entire plant wilts suddenly. Infested vines usually die beyond the point of attack. Sawdust-like frass or droppings near the base of the plant are the best evidence of squash vine borer activity. If the stem is split open, one to several borers usually is present.


          • Control


          • Cultural:

          • After harvest is complete, deep tillage or removal of crop residue will help to delay and/or reduce infestation the next cropping season.


          • Chemical:
            The key to squash vine borer management is controlling the borers before they enter the stem. Therefore, they must be controlled on a preventive basis; once inside the vine, insecticidal control is ineffective. Poor timing of sprays is the usual cause of inadequate control. Monitor plants weekly for initial signs of the borer’s frass or droppings  at entrance holes in the stems. Use two to three insecticide applications 7 days apart to control newly hatching larvae and continue to monitor for additional activity. A second approach is to initiate a weekly application of an insecticide starting when vines begin to run. Sprays need to penetrate the canopy to cover the vines to be effective.
          • Aphids Green Peach Aphid (Myzus persicae):
          • Green peach aphid colony.

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              Aphids can move into pumpkin fields in large numbers from surrounding vegetation, carrying viruses as it moves and feeds from one plant to another. Aphids also cause problems by weakening the plant through feeding, and both whiteflies and aphids are also vectors of viral diseases.
              Damage usually becomes obvious on cucurbits after the vines begin to run. Congregating on lower leaf surfaces and terminal buds, aphids pierce plants with their needle-like mouthparts and extract sap. When this occurs, leaves curl downward and puckers. Wilting and discoloration follow. Aphid damage weakens plants and may reduce fruit quality and quantity. Honeydew secreted by aphids makes plants sticky and enhances development of black sooty mold on plant foliage.

               

              Control

               

               

               

               

              Control weeds along drains, banks, roads, and other non-cultivated areas that contribute directly to the aphid problem.
              It is important to treat early to insure that the aphids do not build up to high levels and treatment should be based on visual counts. Early treatment does not prevent virus introduction; treating, however, may help reduce spread of the virus if aphid colonies are present.

            • Army worm:

              • Several species of armyworm (Spodoptera spp.) and looper (Trichoplusia spp.) larvae can also damage pumpkins. These larvae feed on foliage and occasionally damage fruit. They can be controlled with registered insecticides and biological controls such as Bacillus thuringiensis.

                 

              • Cucumber Beetles: (Acalymma vittatum, Diabrotica undecimpunctata)


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                These beetles are vectors of bacterial wilt. Plants infected with the disease wilt quickly with leaves drying out prior to plant death. The causative bacteria, Erwinia tracheiphilia lives in the bodies of these beetles, which introduce the bacteria into the plants through the fecal contamination of feeding wounds. This is the only natural method of infection known. Beetles also spread squash mosaic

                virus.

                 


                 

                 

                Damage:

                Cucumber beetles are important pests of cucurbits. They cause four types of damage. Seedling destruction, flower and foliage damage, root feeding, and transmission of bacterial wilt disease. The beetles feed on newly emerged cotyledons and stems, and they have been reported to go below ground level and feed on plants as they emerge. Adults lay eggs in the soil near the seedlings and larvae soon hatch and begin feeding on roots of the cucurbits. Larvae chew holes and tunnel into the roots. Damage by the larvae, except under dry conditions, is usually considered minor. Probably the most serious damage by cucumber beetles is from transmission of bacterial wilt. Bacterial wilt can kill many plants in a field and seriously reduce the yield. The striped cucumber beetle and the spotted cucumber beetle have very similar life cycles and both can carry the bacteria, but both are not equally important pests on cucurbits

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                Control Practices:

                 


                Chemical control is often needed, particularly in commercial plantings. To prevent cucumber beetle damage to seedlings, treat when one beetle per 10 feet of row is found. To prevent bacterial wilt, treat when one beetle per 100 feet of row is found. Usually, a soil insecticide is used at planting time for control of cucumber beetles during the seedling stage and foliar treatments are applied as needed.

                 

                 

                Insecticides:

                Application of an insecticide is usually recommended as soon as the plants begin to emerge through the soil. For prevention of bacterial wilt, it is often advisable to spray at 5-day intervals, beginning when seedlings emerge or after transplanting and continuing the schedule until vines run. If rain occurs within the 5-day period, repeat the treatment promptly and then return to the regular 5-day treatment interval.
                Sprays prepared from wettable powders are less phytotoxic than sprays prepared from emulsifiable concentrates. Malathion® may cause injury to plants if applied before they start to vine. Malathion® may cause some foliar burning and should not be applied when plants are wet.

                Viruses:

                Viruses cause some of the most serious diseases of pumpkins. Of the viruses affecting pumpkins are those of most importance are transmitted by aphids, whiteflies, leafhoppers, and beetles. Virus transmission is specific, however. Viruses such as cucumber mosaic virus (CMV), watermelon mosaic virus (WMV), and papaya ring spot virus (PRV) are transmitted by aphids in a non-persistent manner, requiring only seconds to a few minutes for the aphids to probe the leaf surface and transmit the virus.

                If possible, other cucurbits should not be grown in the same area prior to planting pumpkins to avoid movement of virus from one crop to another. It is always desirable to plant succeeding crops of pumpkins or other cucurbits upwind of previously planted cucurbit crops. Other crops such as peppers may also harbor a number of viruses that can also affect neighboring cucurbit crops.

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