Settling and Ovipositional Behavior of Bactericera cockerelli (Hemiptera: Triozidae) on Solanaceous Hosts Under Field and Laboratory Conditions.

Potato psyllid, Bactericera cockerelli (Šulc), is a seasonal insect pest in the Lower Rio Grande Valley of Texas, where it transmits the bacterial pathogen "Candidatus Liberibacter solanacearum" that causes zebra chip disease of potato. Studies were conducted to evaluate host preference of B. cockerelli adults for different plant species, and plant size and density. Settling and oviposition behavior of B. cockerelli was studied on its wild and cultivated solanaceous hosts, including potato, tomato, pepper, eggplant, and silverleaf nightshade, under both field and laboratory conditions. Naturally occurring B. cockerelli were used to evaluate host preference under open field conditions throughout the growing season. Settling and oviposition preference studies in the laboratory were conducted as cage-release experiments using pairs of plants, and observations were recorded over a 72-h period. Results of field trials indicated that naturally occurring B. cockerelli preferred potato and tomato equally for settling and oviposition, but settled on pepper, eggplant, and silverleaf nightshade only in the absence of potato and tomato. Under laboratory conditions, B. cockerelli adults preferred larger host plants, regardless of the species tested. Results also showed that movement of B. cockerelli was minimal after initial landing and settling behavior was influenced by host plant density. Lone plants attracted the most psyllids and can be used as sentinel plants to monitor B. cockerelli activity. Information from both field and laboratory studies demonstrated that not only host plant species determined host selection behavior of B. cockerelli adults, but also plant size and density.