PLANT RESISTANCE Grass Species and Endophyte Effects on Survival and Development of Fall Armyworm (Lepidoptera: Noctuidae)

Grass selections including 10 zoysiagrasses, 18 paspalums, 34 Bermuda grasses, tall fescue, creeping red fescue, and perennial ryegrasses with andwithout endophyte were evaluated for potential resistance to fall armyworm, Spodoptera frugiperda (J. E. Smith), larvae. Laboratory evaluations assessed the degree of antibiosis among 70 grass lines to Þrst-instar fall armyworms. When all parametersmeasuredwere considered, the trend in resistance to fall armywormamong endophyteinfected (E ) and endophyte-free (E-) cool season grasses from greatest to least was: ÔDawsonÕ E APR 1234 ÔDawsonÕ EÔRosalinÕ E Lp 5425, ÔRosalinÕ E-, ATF 480 ÔTulsaÕ or: E slender creeping red fescue E turftype perennial ryegrass Eslender creeping red fescue E forage-typeperennial ryegrass Eforage-typeperennial ryegrasses, andE tall fescue Eturf-type tall fescue. Among warm season grasses larval weight gain was reduced on all zoysiagrasses. Larval weight gain also was lower on the Bermuda grasses ÔTifsportÕ, ÔTifgreenÕ, 97Ð4, 97Ð14, 97Ð22, 97Ð28, 97Ð39, 97Ð40, 97Ð54, 98Ð15, 98Ð30, and 98Ð45 than when larvae were fed ÔTulsaÕ tall fescue or the diet control. Only APR1234 and ÔDawsonÕ creeping red fescue reduced larval survival to the same extent that was observed for zoysiagrasses. Survival on Bermuda grasses was least on 97Ð8. Seashore paspalums were only rarely less susceptible to fall armyworm than tall fescue, although pupal weights wereconsistently loweron ÔTemple1Õ and ÔSea Isle 1Õ paspalums than thaton ÔTulsaÕ tall fescue.Genetic resistance to key grass pests can reduce insecticide use and simplify management of these cultivars.