MANAGEMENT OF PINK BOLLWORM
Pink bollworm management objectives are to keep infestations below economically damaging levels in the current season without creating secondary outbreaks of other pests. A successful management program will also reduce the overwintering population that will threaten next year’s crop. Management of pink bollworm populations depends on cultural practices, the use of sex pheromone for adult moth mating disruption and monitoring and insecticide applications where needed. Shredding and disking crop debris promptly after harvest reduces overwintering populations to a level that can be managed economically. CheckMate® PBW may be used in an IPM program in conjunction with insecticides in areas of high pressure, where migration from adjoining fields is occurring, or where control of secondary pests is needed.

PINK BOLLWORM BIOLOGY *,‡
Pink bollworm is a widely distributed pest of cotton in Arizona, southern California, Mexico, New Mexico and Texas. As many as 5 generations may occur each year. Larvae that overwinter in diapause produce adults that are the source of new infestations in spring. In low deserts, adults emerge from overwintering larvae as early as February. Peak emergence usually occurs from April to early June. Accumulation of degree-days starting on January 1 can predict the spring emergence peak. Implementation of early season management practices can often be based on accumulated heat units for pink bollworm in relation to crop stage of growth (first square). Utilizing a 55° F/86° F degree-day calculation:

First PBW emergence (from Jan.1) 500 HU

Pinhead square (after planting) 700 HU

Peak PBW emergence (from Jan.1) 1180 HU

First susceptible boll (after planting) 1580 HU

Approximately 750 heat units (degree-days) are required for each summer generation of pink bollworm. Adults actively feed and mate at night and hide in sheltered places during the day. Eggs are laid singly or in small groups on all fruiting structures. Eggs are seldom seen because they are small and often hidden under the calyx of young bolls. Newly hatched larvae are white. In the third instar a pink color pattern appears that deepens to reddish pink in the final instar. Populations increase slowly while larvae are feeding in squares, but increase rapidly as soon as green bolls are available.

* Integrated Pest Management for Cotton in the Western Region of the United States. University of California, Pub.3305 1984.

‡ Pink Bollworm Management. Newsletter of the Pink Bollworm Action Committee, National Cotton Council. Vol. 1 No. 2.