Population dynamics and management of potato leafhopper and other insect pests in forage systems
The potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae) is a major insect pest of alfalfa in the north central and northeastern United States. Studies were conducted from 1994 through 1996 to better understand the population dynamics of potato leafhopper in Iowa, as well as improve sampling and management of this and other alfalfa pests. The specific objectives of this dissertation were to (1) understand the population dynamics and diurnal activity of potato leafhopper in Iowa forage systems; (2) determine the effect of alfalfa-forage grass intercrops on potato leafhopper, as well as other alfalfa insect pests and predators; (3) assess the impact of intercropping on forage growth characteristics for determining the feasibility of intercropping as a management tactics; and (4) develop grower-oriented sampling techniques and a management program for potato leafhopper in alfalfa. These studies improved the sampling and management of potato leafhopper and other insect pests in alfalfa. We found that (1) potato leafhopper populations can reach economic levels in any of the three alfalfa crops; (2) there are differences in the number of potato leafhoppers captured at different times of the day; (3) alfalfa-forage grass intercrops reduce insect pest populations compared to monocultures; and (4) the sticky trap sampling technique seems the most promising technique for use in a management program.