Performance of Fall Armyworm Preimaginal Development on Cultivars of Tropical Grass Forages

(J.E. Smith) (Lepidoptera: Noctuidae) is a polyphagous pest species capable of feeding on almost all forage and grain crops, although the food quality for the larvae likely varies among plant species and cultivars. The cultivation of grass forage species with grains has increasingly been adopted in Brazil, within both no-tillage and crop-livestock integration systems. In this study, we evaluated the performance of larvae on 14 forage cultivars of , , and , which are widely used in integrated cropping systems in Brazil. The biological performance of varied among the cultivars. The larval survival rates were lower on 'Massai' and 'Tamani' cultivars. The insects had the highest performance indexes on 'Paiaguás', 'Marandu', and 'Xaraés' cultivars, followed by , previously proposed as a standard grass forage for comparisons with other species. On , the insect had the lowest performance indexes, with values equal to zero when feeding on the 'Massai' and 'Tamani' cultivars. These results will help make management decisions when cultivating grass forage plants in crop production systems in which infestation is of concern.