Integration of Cotton Plant Resistance With Selected Organic Boll Weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae) Control Tactics

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is one of the key pests and limiting factors to cotton production in conventional and organic systems. We assessed the use of resistant and susceptible cotton cultivars, a neem-based insecticide (Natuneem), and trapping with an A. grandis grandis aggregation pheromone as possible control tactics. In the first of two growing seasons we evaluated resistance of colored fiber cotton cultivars BRS 200, BRS Rubi, BRS Safira, and BRS Verde, and white fiber cotton BRS Aroeira, against A. grandis grandis attack. In the second growing season we assessed three colored cotton cultivars grown in and without close association of BRS Aroeira, and two control tactics: the neem-based pesticide and trapping. Because BRS Aroeira showed resistance against A. grandis grandis in the first growing season, it was selected to be planted in close association with more susceptible colored cultivars in the second growing season. Field plots with white and colored cotton cultivars reduced the need to control A. grandis grandis using the neem-based pesticide. Control by the neem-based pesticide and by trapping were of comparable value although the traps provided measurable control during early cotton growth stages and the neem-based pesticide provided measurable control during later cotton growth stages.