The arrival of kudzu bug to Arkansas is not “if,” but “when,” Jeremy Greene professor of entomology at Clemson University, told a crowd of more than 325 on Friday at the Tri-State Soybean Forum.Click here to see more...
“You will get kudzu bugs here in Arkansas,” he said. “It’s just a matter of time.”
Greene presented results of research on this invasive pest that exploded from the time it was first found in a handful of counties in Georgia in 2009 to span the South to the eastern edge of the Mississippi River. Kudzu bugs, which can produce two generations a growing season, can impact soybean yields.
Greene said research indicates that pyrethroids seem to have the greatest effect on kudzu bug populations and the key is to keeping the bug in hand is controlling the nymphs.
Terry Spurlock, extension plant pathologist for the University of Arkansas System Division of Agriculture, discussed research on the distribution of aerial blight in soybean fields that were in annual rotation with rice.
The inoculum for aerial blight fares well in the wet conditions of rice fields and will persist and accumulate in the soil. “It’s a big tough disease. It just sort of kicks the door in and does what it wants to do,” he said.
Spurlock said research shows a correlation between elevation and occurrence of the disease, with higher levels of infection correlating with lower elevations in the field and in bends in the levees.
“That inoculum is built up in the soil and it’s ready to go,” he said. “If we get cool and we get wet, at canopy closure, we better be hunting aerial blight.”
Breeding salt-resistant soybeans
Buildup of salts in the soil can be deadly to soybeans, said Grover Shannon, professor of soybean genetics and breeding at the University of Missouri. Shannon said Arkansas maybe the No. 1 state in the Delta where it comes to salt problems.
Managing salt in soil is virtually impossible, so soybean growers need to turn to varieties that exclude salts from being drawn up the plant and into the leaves, he said.
Shannon said research shows there are three types of soybeans, Glycine tomentella, G. argyea and G. soja, the wild soybean, that all show excellent resistance to salt.
“We want to move genes from these three into Glycine max” the crop soybeans, he said.
Shannon recommended that growers have their wells and soils checked for salts and if a farm’s neighbors are seeing salt issues, growers may want to use a salt-resistant variety, “just in case.”