Soybean leaf damaged by soybean vein necrosis virus
A new publication funded by the North Central Soybean Research Program and co-authored by a Purdue Extension plant pathologist will raise awareness of soybean vein necrosis virus.
The publication is part of the NCSRP's multistate Soybean Disease Management Series, which aims to help soybean farmers identify and economically manage diseases to minimize yield loss.
Soybean vein necrosis virus, or SVNV, is fairly new to the north-central U.S. The publication provides information to soybean growers about what the disease is, symptoms, vectors, laboratory detection, yield loss, economic impact and management.
"We don't know a lot about the virus right now because it is very new, but we are doing research to try to understand how it could impact yield," Kiersten Wise said. "We want to make sure growers know how to identify the virus in their fields so they aren't applying ineffective pesticides to try to manage the disease."
SVNV is transmitted from plant to plant by tiny, winged insects called thrips. Adult thrips, about one-sixteenth of an inch long, have yellow bodies, dark thoraxes and two black crossbands on their forewings. They feed on plant juices, primarily on the undersides of leaves and pollen when flowers are present.
Wise said that in Indiana the virus is widespread from the southern part of the state near Kentucky to the northern border with Michigan.
"We usually see it appear first in the southern part of the state, but by the end of the season, it can almost be in every field," she said.
SVNV symptoms begin with vein clearing followed by chlorosis, which appears as light green to yellow blotchy patches near the main vein of the leaf. Leaves might appear scorched, and affected leaf tissue might die during late stages of infection.
Researchers will continue to monitor the disease and assess potential impact in an effort to determine the best management options. Future recommendations will be developed as researchers learn more about SVNV.
Soybean growers can download Soybean Disease Management: Soybean Vein Necrosis Virus for free at https://www.extension.purdue.edu/extmedia/BP/BP-186.pdf. It also can be ordered from the Purdue Extension Education Store at http://www.the-education-store.com or by calling 1-888-EXT-INFO (1-888-398-4636).