Comparison of Aphidius ervi behavior on Medicago sativa stems with and without glandular trichomes

Host-plant resistance in Medicago sativa has warded off Empoasca fabae as a primary pest with glandular trichomes, but may reduce the biological control efficacy of Aphidius ervi. Previous studies on parasitoids and glandular trichomes have shown that parasitoid activity is reduced in the presence of glandular trichomes, but they were done on a limited number of cultivar types. This study intends to investigate A. ervi behavior on many M. sativa cultivars with and without glandular trichomes, and with varying trichome density. Biological control efficacy will be measured by the number of green and pink morphotypes of Acyrthosiphon pisum parasitized. Before the experiments begin, an ethogram will be developed after a period of behavioral observation.