Response of Selected Bermudagrass Cultivars to Bermudagrass Stem Maggot Damage

Information regarding the susceptibility of currently grown bermudagrass [Cynodon dactylon (L.) Pers.] cultivars to the bermudagrass stem maggot (BSM; Atherigona reversura) could aid forage producers with the implementation of integrated pest management (IPM) strategies to manage this exotic pest. The objectives of this research were to compare the severity of damage among selected cultivars and quantify the phenotypic variation in cultivar response to the BSM among selected bermudagrass cultivars. Eight Cynodon cultivars were used in this study. Flies collected from infested fields were introduced six times throughout the 4-wk growing period to the cultivars, which were grown in the greenhouse and contained in acetate and mesh enclosures. The number and percent of tillers damaged depended on cultivar in that cultivars with greater tiller density exhibited the greatest damage. When corrected for cultivar differences in the number of total tillers per pot, the stargrass (Cynodon nlemfuensis Vanderyst) cultivars and hybrids had a lower percentage of their tillers damaged (P < 0.10) by the presence of BSMs than the fine-textured cultivars, except for 'Russell' in 2012. Presence of the BSM was coincident with a lower tiller count, increased tiller diameter, and darker leaf color, though no difference in any other physical characteristic was observed. The results showed that stargrass and stargrass hybrids are less susceptible to damage by the BSM and should be employed in IPM strategies wherever these cultivars are adapted.