Bermudagrass Stem Maggot: Devastating New Pest Problem for Southern Hay Producers.

Bermudagrass is the most important perennial forage crop grown for pasture and hay in the Southeast (~ 20 million acres).  Bermudagrass Stem Maggot (BSM) (Atherigona reversura Villeneuve) is an invasive insect pest that reduces yield of forage bermudagrass hay if it is not controlled.  The pest is native to SE Asia, was first documented in North America near Los Angeles, California in 2009 and has since spread throughout the southeast, infesting bermudagrass hayfields as far north as Kentucky and as far west as Texas. Greenhouse studies indicated that fine stem cultivars are more susceptible to BSM.  A field study compared spray controlled plots to unsprayed plots in Tifton in 2015 and 2016.  For clippings in mid to late summer, BSM reduced yield of Alicia and Russell over 60%.  Tifton 85 and Coastcross II also had some yield reduction but not as severe. A screening of 300 bermudagrass accessions resulted in a four or five accessions having a high level of tolerance to BSM.