The sweetpotato whitefly, Bemisia tabaci (Gennadius), B biotype, presents a unique problem for vegetable growers by serving as a vector of plant viruses and by inducing physiological disorders of leaves and fruit. An action threshold of a single whitefly is necessary because of the threat of disease in many areas and growers rely heavily on a single class of insecticides (neonicotinoids) for wh...

Whiteflies, Hemiptera: Aleyrodidae, Bemisia tabaci, a complex of morphologically indistinquishable species(5), are vectors of many plant viruses. Several genera of these whitefly-transmitted plant viruses (Begomovirus, Carlavirus, Crinivirus, Ipomovirus, Torradovirus) include several hundred species of emerging and economically significant pathogens of important food and fiber crops (reviewed b...

Twenty-eight greenhouse screening materials, with predetermined airflow resistance values, were evaluated for exclusion of the silverleaf whitefly Bemisia argentifolii Perring & Bellows and thrips from a mixed-species population. Screens differed in exclusion efficacy, expressed as a percentage of the fiberglass window screen control and at an approach velocity of 92 m/min, from -35 to 94% for ...

Toxin complex a (Tca), a high molecular weight insecticidal protein complex produced by the entomopathogenic bacterium Photorhabdus luminescens, has been found to be orally toxic to both the Colorado potato beetle, Leptinotarsa decemlineata, and the sweet potato whitefly, Bemisia tabaci biotype B. The 48 hour LC50 for Tca against neonate L. decemlineata was found to be 2.7 ppm, and the growth o...

Begomoviruses (family Geminiviridae) are whitefly-transmitted, plant-infecting single-stranded DNA viruses that cause crop losses throughout the warmer parts of the World. Sweepoviruses are a phylogenetically distinct group of begomoviruses that infect plants of the family Convolvulaceae, including sweet potato (Ipomoea batatas). Two classes of subviral molecules are often associated with begom...

A study was conducted to evaluate the use of reflective mulch and host plant resistance for the management of the sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), in watermelon [Citrullus lanatus var. lanatus (Thunberg) Matsum & Nakai]. Whitefly abundance data were collected under both greenhouse (caged and uncaged) and field conditions. Consistently, a reflective mulc...

A pathogen may cause infected plants to promote the performance of its transmitting vector, which accelerates the spread of the pathogen. This positive effect of a pathogen on its vector via their shared host plant is termed indirect mutualism. For example, terpene biosynthesis is suppressed in begomovirus-infected plants, leading to reduced plant resistance and enhanced performance of the whit...

Seven insecticides, viz. Megamos 20SL, Actara 25WG, Polo 500SC, Sitara 25WP, Nighaban 20EC, Thiodan 35EC and Confidor 200SL were evaluated at their field recommended doses for their efficacy against whitefly (Bemisia tabaci Genn.) on cotton, at the farmer’s field in Dera Ghazi Khan during 2007. The insecticides were applied at ETL’s of whitefly. All the test insecticides caused significant mort...