Interaction of silverleaf whitefly (Homoptera: Aleyrodidae) with cantaloupe yield
1995
Riley, D.G. | Palumbo, J.C.
A range of population levels of silverleaf whitefly, Bemisia argentifolii Bellows & Perring [previously b-strain sweetpotato whitefly, Bemisia tabaci (Gennadius)] was evaluated in 3 field experiments for effect on cantaloupe, Cucumis melo L., quality and yield. An increase in total numbers of immature whitefly was associated with significant declines in harvested cantaloupe weight and number of boxes harvested, a decrease in fruit size and total dissolved solids, and an increase in sooty mold. In the first experiment, a positive correlation of whiteflies to downy mildew, Pseudoperonospora cubensis (Berkeley and Curtis) Rostow, was observed. In Texas, regression analysis of individual whitefly life stages with yield parameters showed that the number of large nymphs was a more precise parameter for estimating effects on melon yield than adults. However, at the high whitefly population density that occurred in Arizona, the number of adults was more precise. Higher R2 values were obtained in Arizona than in Texas. Adults were sampled at the 3rd leaf node in both locations. Estimates of the mean adult silverleaf whitefly density resulting in 5 and 15% dollar-yield loss were 3 and 10 adults per leaf under high (Arizona) whitefly population density. Estimates of the mean total nymph density resulting in 5 and 15% dollar-yield loss under low (Texas) and high (Arizona) whitefly population densities were 0.1 and 0.4 (Texas) and 0.5 and 2 (Arizona) nymphs per square centimeter of leaf area, respectively.
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