Watch for charcoal rot in dry areas
A soybean field with plants affected by charcoal rot. Symptoms of charcoal rot, caused by the soilborne fungus Macrophomina phaseolina, are apparent in soybean fields located in areas of the state that have been hot and dry. Symptoms in affected fields appear as individual plants or patches of wilted and dead plants. Gray to black "specks" will be apparent on the lower stems of affected plants when the epidermis is shaved off with a knife. These specks, known as microsclerotia, are the survival structures of M. phaseolina.
Management of charcoal rot requires an integrated approach. Although no soybean varieties have complete resistance, varieties can differ in their levels of susceptibility to the disease. Macrophomina has a wide host range, which includes corn, sorghum, and sunflower, so crop rotation alone may not provide complete management. Practices that reduce drought stress may help, such as avoiding high seeding rates and using conservation tillage practices that conserve soil moisture. Foliar and seed treatment fungicides do not provide protection against charcoal rot.
Dark specks (microsclerotia) can be observed inside the lower stems of soybean plants affected by charcoal rot.
- New calculator can help soybean farmers with seed decisions
- U.S., Brazil close to ending cotton trade rift
- U.S.-Japan trade talks hit new farm exports snag
- Ag markets posted a general comeback Wednesday
- Midwest grain growers ‘Invest an acre to feed the world’
- Ag markets turned mixed around midsession Wednesday
- Activists fighting Golden Rice even more in 2014
- U.S. GMO labeling foes triple spending in first half of this year
- Source shows half of GMO research is independent
- White House issues veto threat on bill to block WOTUS rule
- East-West Seed signs marketing collaboration with Monsanto
- How much corn can the ethanol industry use?