CORNELL COOPERATIVE

EXTENSION OF ONEIDA COUNTY 121 Second Street Oriskany, NY 13424-9799 (315) 736-3394 or (315) 337-2531 FAX: (315) 736-2580

Striped Cucumber vittata (Fabricius)

Injury: Both adults and larvae of the striped have chewing mouthparts. Because congre- gate in large numbers on newly emerging cucumber, melon, pumpkin, and squash plants, they may do severe feeding damage in a very short time - almost overnight.

The bacteria Bacillus tracheiphilus Erw. Sm., survives the winter in the gut of the overwintering beetles. In the spring the beetles inoculate the disease into the plant tissues as they feed, spreading disease from plant to plant and field to field wherever infected beetles feed. The is also a vector of cucumber mosaic disease. The summer generation of larvae feed on the plant parts below the soil surface, whereas the adult beetles feed on the stems, leaves, and fruit of cucurbits.

Description: Adults: The adult beetles measure about 1/5 inch (5 mm) long by 1/10 inch (2.5 mm) wide. The upper body surface is about equal black and yellow, the folded wing covers forming three longitudinal black stripes. Eggs: Eggs are orange-yellow in color and are laid around the base of the host plants, often below the soil surface or in cracks in the ground. The eggs hatch in about one week. Larvae: The white larvae that hatch from the eggs feed for a period of 2-6 weeks, depending on temperature, on the roots and underground portion of the plant, se- verely damaging the root system. When full grown, the larvae are about 1/3 inches ( 8 mm) long. Pupae: The larvae transform to pupae in the soil near the base of the plants on which they have been feeding. The white pupae transform into adult beetles in about one week.

Life History: The adult beetles hibernate under trash or if such protection is not available, they will burrow into the soil below the frost line. The adults emerge from April to June usually before the cucurbit plants are up and feed for a time on pollen from flowers of apple, horse chestnut, lilac, and many others. When squash and cucum- bers start to shoot up, the beetles quickly congregate on them.

After feeding for some time, the adults mate and the females begin to lay eggs. Eggs are laid wherever the female is feeding, often near the base of the plant. In a week or more the eggs hatch and the larvae work their way to the cucurbit. Here they burrow into the root and underground stem tissue and feed for about a month. The mature larva constructs an earthen cell a few inches below the soil surface and pupates. The adult beetles emerge in late August or September and feed on pollen until killing frosts occur.

Management: This insect is difficult to control because the adults attack plants close to or even below ground level. Control is important, however, to prevent disease. Fall cleanup by disposing of old cucurbit plants reduces potential habitat for the beetles.

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Cornell Cooperative Extension provides equal program and employment opportunities. NYS College of Agriculture and Life Sciences, NYS College of Human Ecology, and NYS College of Veterinary Medicine at Cornell University, Cooperative Extension associations, county governing bodies, and U.S. Department of Agriculture, cooperating. —Page 2

Researchers are working on breeding varieties of squash that show resistance to cucumber beetles. Mechanical barriers such as row covers or wire or cloth screen protectors made in the form of cones or hemispheres can keep beetles out. Be sure edges are sealed to the ground so that do not move in underneath them. Place barriers over newly set transplants or newly seeded beds. Remove these protection devices when the plants start to out- grow them or when plants start to bloom. Effective mechanical barriers can eliminate the need for insecticidal treatment.

Row cover over raised bed

This publication contains pesticide recommendations. Changes in pesticide regulations occur constantly, some materials mentioned may no longer be available, and some uses may no longer be legal. All pesticides distributed, sold, and/or applied in New York State must be registered with the New York State Department of Environmental Conservation (DEC). Questions concerning the legality and/or registration status for pesticide use in New York State should be directed to the appropriate Cornell Cooperative Extension Specialist or your regional DEC office. READ THE LABEL BEFORE APPLYING ANY PESTICIDE.

Prepared by: Carolyn Klass, Senior Extension Associate, Department of Entomology, July 1973; Revised April 1991.

Retyped 2006