ABSTRACT
In a greenhouse experiment we documented the effects of low, medium, and high nitrogen in cotton on development and honeydew production by the sweetpotato whitefly, Bemisia tabaci. Nitrogen status of cotton plants was manipulated by irrigation with 0.5, 2.5, or 5.0 mmol-l-1 nitrogen fertilizers. Although the fertilization treatments produced large differences in plant growth and flower production, only subtle differences were found in whitefly development. No differences among treatments were found in stage specific survival, or time whiteflies spent in each stadia with the exception of the first. Whiteflies on high nitrogen plants passed the first stadium in less time than whiteflies on low or medium nitrogen plants. Our preliminary analyses indicate that although whitefly nymphs on high nitrogen plants initiated the production of honeydew droplets before nymphs on other treatments, no differences in the amount of honeydew produced were observed after initiation.
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