ABSTRACT
This chapter deals with some important aspects of the broad field of whitefly-plant relationships. It examines the behavioural and ecological aspects connected with host location; selection of host species and parts of plant for feeding and oviposition; and the spatial distribution within and between host plants. The nymphal stages of B. tabaci are sessile and mobility during the entire development period is limited to the exploratory crawling of the first-instar nymphs for a brief period. Leaf age is a major factor influencing host selection by B. tabaci since the females prefer young leaves for oviposition. On soybean cultivars, B. tabaci laid more eggs on young leaves than on mature ones. Young leaves may serve as the best compromise, meeting nutritional requirements of the adults and providing conditions for optimal development of the immatures. Leaf hairiness is an important factor, strongly influencing host selection by B. tabaci.
