The soybean stem fly found on Persian clover as an alternative wintering host in the soybean belt of South America
The soybean stem fly (Melanagromyza sojae) is a widely distributed and highly damaging soybean pest, recently introduced to Brazil and neighboring countries. The bioecology of this pest under South American growing conditions is largely unknown, including how infesting populations survive throughout the winter. Fly larvae collected in August 2019 from Persian clover Trifolium resupinatum in Santa Maria, southern Brazil, were identified as M. sojae via molecular characterization. Persian clover is commonly grown as a cattle forage crop in this region. This is the first report of M. sojae occurring on T. resupinatum, and of any overwintering host available to the pest in the New World. This finding will help understand the bioecology of M. sojae populations in Brazil, so that adequate pest management strategies can be planned for this invasive pest.