Resistance in Lycopersicon spp. to the Tobacco Flea Beetle13

Abstract

When young and healthy leaves of accessions of Lycopersicon hirsutum Humb. and Bonpl. and L. hirsutum f. glabratum C. H. Mull. were tested in a greenhouse at Beltsville, Maryland, they had a strong repelling effect on adult tobacco flea beetles, Epitrix hirtipennis (Melsheimer). However, young leaves that had been divested of glandular exudate by being washed with 75% ethanol and unwashed senescent leaves on older plants did not repel the beetles. All accessions were susceptible to beetles in the larval stages. All varieties of L. esculentum Mill. and accessions of L. peruvianum var. dentatum Dun., L. Pimpinellifolium (Jusl.) Mill., and L. glandulosum C. H. Mull. that were evaluated were susceptible to both adults and larvae.