Life History

The boll weevil belongs to a family of insects that is strictly phytophagous. This group is highly host specific and

FIGURE 1 Boll weevil on cotton leaf.

generally prefers flower buds for feeding. Cotton (Gossypium spp.) is the principal host plant of boll weevil, but it also develops on certain species of the related genera Thespesia, Cienfuegosia, and Hampea. The boll weevil passes the winter in diapause in the adult stage sheathed beneath brush and ground litter and in other protected locations in or around cotton fields. In arid areas, overwintering sites may be associated with increased moisture habitats such as near irrigation canals and rivers. Winter survivors emerge from overwintering sites in the spring and begin feeding on the tips of cotton seedlings and squares (i.e., the cotton flower buds). Weevils that emerge before cotton plants have begun to form squares, feed on leaf buds and growing terminals, and live for only a week or two; those that emerge later produce eggs for 3 to 6 weeks. Later generations survive the winter in a diapause state. The female deposits eggs singly in the bottom of punctures she makes in the cotton squares and later in the season in bolls. Overwintered females produce fewer than 100 eggs, but later generations produce 300 or more eggs. The average female's rate of reproduction is 5 or 6 eggs a day. Depending on the temperature, larvae hatch in 3 to 4 days. Larvae feed for 7 to 14 days and pupate. Adults emerge 3 to 6 days later.

A sex pheromone facilitates mating, after which the females begin laying eggs in 3 to 5 days. Two to seven generations can occur in a season. However, as many as 10 generations may develop under favorable conditions. Late in the season as cotton ceases to produce fruit, boll weevils move in large numbers from cotton fields to overwintering sites. Only 1 to 20% of weevils survive the winter. Reduced survival is seen after unusually cold winters, and unusually dry summers also cause some mortality through loss of moisture in overwintering sites.

Bee Keeping

Bee Keeping

Make money with honey How to be a Beekeeper. Beekeeping can be a fascinating hobby or you can turn it into a lucrative business. The choice is yours. You need to know some basics to help you get started. The equipment needed to be a beekeeper. Where can you find the equipment you need? The best location for the hives. You can't just put bees in any spot. What needs to be considered when picking the location for your bees?

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