|
What is it?
Cucumber beetles come in two forms, the spotted cucumber beetle of the diabrotica species and the striped cucumber beetle of the acalymma species. Both are common pests of the curcurbit family and can be of harm to the many plants in the curcurbit family, including cucumbers, gourds, muskmelons, pumpkins, watermelon, and summer and winter squash. Cucumber beetles are especially fond of melons, squash, cucumbers and pumpkins. It is essential to control cucumber beetle populations because they contribute to the spread of two other curcurbit family killers, mosaic virus and bacterial wilt.
What does it look like?
Cucumber beetles are typically yellow and green with black and/or spots on their backs. They grow only up to 1/16 inch and will scurry away quickly when they are disturbed for any reason. Curcurbit family plants with cucumber beetle damage will have holes in their leaves which appear to be chewed. The cucumber beetle damage and chewed, ragged holes may also extend to the leafstalks and stem areas of the curcubrbit family plants. The holes vary in size and may join together to form larger openings. Seedlings are especially susceptible and in many cases whole plants can wither, wilt, and die prematurely if left untreated.
How does it manifest?
Cucumber beetles over winter on plant debris and weeds. In the spring they emerge and start feeding on a variety of plants, especially those in the curcurbit family which they attack as soon as the curcurbits have been planted. As they feed, cucumber beetles will chew holes in the leaves and stems, often leaving the curcurbit family plants looking riddled as if by a shotgun. These leaves quickly wither, dry out and die. Mature cucumber beetle females lay orangish-yellow eggs in the soil at the bases of the curcurbit plants. The grubs which hatch from these eggs then begin to feed on the root system as well as the base of the infested curcurbit plant. This can cause the curcurbit family plant to become growth stunted or lead to wilting and premature death. The grubs of cucumber beetles are white and slender and can feed for many weeks in the soil before pupating and emerging as adult beetles. Fortunately, cucumber beetles produce only one generation per year in the United States norther regions. However, the southern regions can fall prey to two to three generations of cucumber beetles per year.
What can you do about it?
When you see the first signs of cucumber beetle damage, use an insecticide which contains either carbaryl, pyrethrins, or diazinon to help control them. Each time you find further damage, repeat the application of insecticide doing so at weekly intervals. It is best to treat plants early in the growing season to prevent the spread of diseases such as bacterial wilt and mosaic virus which the cucumber beetles can spread as they feed.
|
| |
