The nymphal stage of whitefly pests is important in terms of its relationship to pest management measures and virus epidemiology. Among the nymphal forms, the active first instar, i.e., crawler, is the only mobile form of immature whiteflies. A study was conducted to determine any influence of vegetable plant species and temperature on net distance moved (between the egg site and final resting site) by crawlers of the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius). Tests were conducted in the greenhouse and under controlled laboratory conditions on five vegetable hosts: cantaloupe, Cucumis melo L.; collard, Brassica oleracea ssp. acephala de Condolle; cowpea, Vigna unguiculata (L.) Walpers; pepper, Capsicum annuum L.; and tomato, Lycopersicon esculentum Miller. The net distance moved was shortest on collard in which the crawler ceased traveling ≈2 mm from where it hatched. The crawler ceased traveling ≈10–15 mm from the site of hatching on the other vegetable host plants. Observations on collard in the laboratory indicate that the crawlers traveled 21 min during the first stadium. No effect of constant temperature over the temperature range of 16–34°C was detected on the net travel distance of the crawlers. These data suggest that among the plant species in this study, collard is highly attractive for feeding and/or it offers suitable feeding sites that are easy to locate by the crawler. The results of this study help define the behavior of crawlers on several host plants.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 95 • No. 4