Populations of the Sweetpotato Whitefly on Cotton Grown in Open-Top Field Carbon Dioxide-Enrichment Chambers

Atmospheric carbon dioxide levels are rising from the current ambient level of ca 350 ul /liter to 500 -600 ul /liter projected for 50to 75 -years hence. In addition, plant scientists are enhancing the CO2 environment to increase photosynthesis which is currently limited by inadequate levels of CO2. There are many questions as to how increases of CO2 might affect other organisms. The growth and feeding response of the soybean looper, Pseudoplusia includens (Walker), to soybeans grown in controlled carbon dioxide atmosphere was studied by Lincoln et al. (1984). Larvae fed at increasingly higher rates on plants from elevated carbon dioxide atmospheres, suggesting that the impact of herbivores on their host plants may increase as the level of atmospheric carbon dioxide rises. During 1984 we sampled sweetpotato whitefly, Bemisia tabaci (Genn.), populations in field plots of