The effect of artificial infestation of the spiralling whitefly, Aleurodicus dispersus Russell at 0, 1, 2, 3, 4 and 5 pairs on caged potted pepper (Capsicum spp.) plants at 2 weeks after planting (WAP), representing the nursery stage, and 6 WAP, representing the field stage, was studied in a screen house. Increasing insect density resulted in a corresponding increase in damage to the leaves, measured as leaf drop. Yield reduction was inversely proportional to the whitefly population, with highly significant correlation coefficients. For instance, yield reductions were 8.8 and 36.5% with 1 and 5 pairs of adult whitefly respectively at 2 WAP, and 7.5 and 32.1% with 1 and 5 pairs respectively at 6 WAP. The chlorophyll, sugar, ash, protein and crude fibre contents of the leaves decreased with increases in level of infestation, although infestation had no significant effect on the nutrient contents of the fruits. The significant impact of A dispersus on vegetative growth, yields and chemical contents of leaves confirm it as an economic pest of pepper in Nigeria.

—Native to the Caribbean islands and Central America, the spiralling whitefly, Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae), has spread to North America, South America, Asia, Africa, Australia and several Pacific islands. A total of 62 natural enemies, including 8 parasitoids, 53 predators and one fungal pathogen, are known to attack the whitefly in different countries. Of the parasitoids, the accidentally or deliberately introduced aphelinids Encarsia sp., Encarsia (?) haitiensis Dozier and E. guadeloupae Viggiani provide control of A. dispersus in many countries. The exotic coccinellid predator Nephaspis oculata Wingo also plays an important role in reducing the whitefly's populations. However, the A. dispersus remains a pest in some countries in the absence of parasitoids. This article reviews current information on biological control of A. dispersus in different countries/states, in particular India, the Pacific islands, Hawaii and countries in West Africa.