Vein necrosis virus showing up in Iowa soybeans
Soybean vein necrosis virus (SVNV) was first confirmed in Iowa last season. Last year we did not see SVNV until August. This past week we identified SVNV in several locations in Iowa.
It is not known yet if earlier symptoms may increase chances of yield loss. We will continue to monitor and provide updates.
The virus belongs to the tospovirus group, which is vectored by thrips and possibly other insects.
Symptoms often begin as chlorotic (light green to yellow) patches near the main veins, which may enlarge eventually becoming necrotic (brown) areas. The veins may appear clear, yellow or dark brown.
The browning of the veins may be especially noticeable on the lower leaf surface, but this may not always occur.
Currently, there are no management recommendations for this disease. Other pathosystems that include thrips and tospoviruses, including tomato spotted wilt virus, focus on resistance and management of the vector. Because of the newness of this disease, there are no known sources of resistance.
Insecticide application only should be considered in fields with a known risk of yield loss.
- Farmland price outlook in 2014 and beyond
- Climate change to cut South Asia's growth 9% by 2100
- Tumbling livestock quotes led ag commodites lower Wednesday
- As risk of drought rises, Australian farmers struggle to invest
- Soybean aphids make an unusual appearance
- Livestock futures led most ag markets lower Wednesday morning
- No El Niño in 2014? Drought-weary California in trouble
- Suspected Bt corn rootworm resistance in Pennsylvania
- BioNitrogen to build second fertilizer plant in Texas
- Soybean aphid numbers on the rise
- Commentary: Setting the record straight on 'Waters of the U.S.'
- Fall burndown benefits go beyond weed control