Cotton - American boll worm
Description
This insect is one of the most dangerous cotton pests. It is highly polyphagous and often found on vegetable crops (tomato), cereals (sorghum and maize) and wild plants (Cleome sp.). It is attracted to cotton during flower and bud formation and flowering about 60 days after germination.
Damage
The African bollworm is an important pest, reducing yields through fruiting point damaged buds, flowers, young and mature bolls.
Larvae move from fruit to fruit, especially when fruiting points are small. They may damage 5-15 fruiting points. Large bolls may be penetrated by larger larvae. Feeding damage often provides entry for disease organisms, which can lead to boll rot. This usually occurs in irrigated cotton, but it can occur during wet periods in areas where cotton is rain-grown.
Life cycle
Eggs are laid at night usually on the tender terminals of the top third of the plant. The female moth will lay 1,000 to 3,000 eggs and after 2 to 8 days, depending on temperature, the eggs hatch and the larvae commence feeding close by the oviposition site. The life cycle can thus be 25 to 35 days depending upon temperature, and six generations per year can be produced three of which could be on cotton.