Sugarcane aphid nearer to VA and threat to sorghum

Sugarcane aphid (SCA) is inundating sorghum in a lot of the southeast and mid-South. As of this week (Aug. 26) we know that a field plot in Kinston, NC (see images below) is heavily infested and at least some have been seen in plots in Lewiston, NC. There is a preliminary siting in the Roanoke, VA area but as of today, this is not confirmed. We have every reason to expect SCA outbreaks in our sorghum fields this season—it’s just a matter of time.

Sorghum is susceptible until harvest and heavy aphid infestations need to be controlled up to that time. From what I have been hearing and seeing, only Sivanto at 4 oz/acre (Bayer CropScience) and Transform at 1.5 oz/acre (Dow AgroSciences) are effective in controlling heavy infestations of this aphid—and for good control it is critical that the applicator focus on coverage all the way to the bottom of the plant. You might have to spray again in 2 weeks following the initial spray and should be prepared to do so though harvest. The crop is not safe until the grain is in the combine. Sivanto has a 21 day pre-harvest interval, and 28 oz can be applied through the season. There is a 14 day pre-harvest interval restriction with Transform, and a maximum of 3 oz can be sprayed for the season. Once nights start to drop into the 50’s efficacy drops—but hopefully, so will aphid activity.

SCA_Mehl_aSCA_Mehl_b