SUSCEPTIBILITY OF BERMUDAGRASS CULTIVARS TO EOREUMA-LOFTINI (LEPIDOPTERA, PYRALIDAE) IN SUBTROPICAL MEXICO

Susceptibility of eight bermudagrasses (Tifton 68, Tifton 78, Tifton 8 5, Gigante, Brazos, Cruza 1, Callie, and NK 37) to the Mexican rice bo rer, Eoreuma loftini (Dyar) was evaluated monthly during 1994 in north ern Tamaulipas, northeastern Mexico. Damage by E. loftini occurred yea r around, peaking in April and December. Borer attack was reduced subs tantially after mowing the pastures to 3-5 cm height. Susceptibility o f the cultivars to borer damage was influenced by stolen width, an imp ortant characteristic for E. loftini tunneling. This relationship betw een stolen width and borer damage was explained closely (R(2) = 0.86) by the curvilinear model y = (1.2 + 0.1757 x(3))(2), where y = borer d amage and x = stolen diameter The widest stemmed bermudagrass, and hen ce the most susceptible to E. loftini, was Tifton 68. Tunneling behavi or of E. loftini, as affected by stem width of host plants, is discuss ed.