Feeding preferences, growth, and development of Mamestra configurata (Lepidoptera : Noctuidae) on Brassicaceae

The growth (increase in body mass) and development (progression to specific instar) of the bertha armyworm, Mamestra configurata Walker, were examined using up to 14 plant lines from five species of brassicaceous plants. Vari etal and breeding lines of Brassica napus L., B. juncea L., B. I;apa L., B. catinata L., and Sinapis alba L. were selected on the basis of differing s eed and foliar glucosinolate levels. No-choice feeding experiments were con ducted with larvae isolated on leaf discs, individual leaves, or entire pla nts of each line. The no-choice tests showed that M. configuruta weight gai n and development varied significantly among host plants tested. Two B. jun cea lines (AC Vulcan and H-Allyl) and the S. alba lines (AC Pennant and L-G S) were the poorest, hosts in terms of larval weight grain, and the two B. juncea lines also significantly slowed development relative to the other li nes tested. Mamestra configurata feeding preference, which was examined usi ng a series of paired leaf disc choice tests, was also significantly differ ent among the lines examined. Two B. juncea lines (AC Vulcan and H-Allyl) w ere signifcantly less preferred than all the other lines examined. The data extends previous work indicating that specific foliar glucosinolates, such as sinigrin, which is predominant in B. juncea, and sinalbin, which is abu ndant in S. alba, may provide brassicaceous crops with some protection from M. configurata. Thus, it may be possible to use foliar glucosinolate level s as predictors of M. configurata feeding damage in the development of bree ding lines for the genus Brassica.