Roles of Host Plants in Boll Weevil Range Expansion beyond Tropical Mesoamerica

摘要: New findings about the food habits of boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), refine current theories range expansion beyond its tropical Mesoamerican origin. The weevil co-evolved with perennial host plants including cotton, Gossypium hirsutum L., and patches were reached by flight, likely instigated competition for limited resources. Boll weevils might have sought nectar, pollen, or both energy to facilitate searching plants. Range was facilitated shifts new plants, in dispersion north, insect subtropical Lower Rio Grande Valley Texas, becoming established only when citrus industry first boomed early 1890s. Commonly grown species bear fruit containing sugars other nutrients that can sustain active over winter spite a 5-mo mandatory fall cotton plowdown. Feeding on cactus fruit, possibly nectars andpollens, makes nonreproductive (used foraging) important dispersal establishment at latitudes. Once south pest moved rapidly through Cotton Belt during warm seasons. To cope cold temperate winters, resorted poorly adapted dormancy response whereby mortality study sites is often 100%. Extensive monocultures support buildup large enough summer populations increase chance few survive infest spring crop. Establishment fringe areas (central southern Arizona, California) pest's into northern Argentina are discussed terms associations reproductive (plants confer sufficient reproduction) nonreproductive, indigenous, exotic