By David Bennett, Delta Farm Press
In early August, alongside seed treatment rice research plots, Gus Lorenz spoke to several trailers full of Ricetec field day attendees about pest problems he’s seen in 2017. The Arkansas Extension entomologist says “grape colaspis really hurt a lot of farmers this year. Many who didn’t have a neonic seed treatment were hit. We saw this in our research plots, we saw it across the state in growers fields where there has been severe stand injury and ultimately they’ll lose yield.”
The seed treatment research just south of Jonesboro, Ark., “is trying to get that early grape colaspis control and then stretch out to gain rice water weevil control when you finally get a flood on the field. We’ve had this same trial duplicated at several locations.”
What Lorenz and colleagues found is “the neonic stood tall and gave us the protection we wanted. We planted about March 29 and finally put the flood on 68 days later.”
Then rice water weevils moved in and “we’re sampling and finding – in our untreated checks and neonic seed treatments – about 40 per core. In a 4-inch core we’re finding 40 rice water weevil larvae feeding on the roots. The threshold is about three.
“Hopefully, we’ll be able to identify the rates that’ll take care of this. It’s got to be cost-effective for the grower. If we can’t get both seed treatments on be cost-effective, we’ll have to look somewhere else.”