A TRIAL comparing the efficacy of seed treatments on loose smut in barley when applied at different slurry volumes was on show at the Liebe Group Spring Field Day in Latham recently.
Loose smut can cause large yield losses in barley crops when left uncontrolled and seed treatments can be an effective form of controlling it, however due to the lifecycle of loose smut, it is crucial that good seed coverage is achieved at application.
Bayer Crop Science market development agronomist Matt Willis said loose smut in barley was the hardest of the smut diseases to control.
"Barley crops infected with loose smut will have the characteristic dark spore filled heads within the crop, but this is actually the appearance of infection from the previous season which has been within the seed," Mr Willis said.
"These spores will infect other neighbouring crops at flowering time leaving the infected grain looking completely normal, while moist conditions at flowering combined with mild temperatures will favour infection.
"When the seed is sown and germination occurs the following season, the fungus will begin to grow within the plant with a mass of spores replacing the head and continuing the disease cycle."
The overall aim of the trial was to compare seed treatments for their efficacy on loose smut in barley.
"We wanted to compare two different application volumes for each product to show the difference in seed treatment performance," Mr Willis said.
"Due to the life cycle of loose smut, a fungicidal seed treatment that penetrates the seed at germination is required to control the disease.
"Most smut diseases can be controlled by a seed treatment that sterilises the surface of the seed but this is not the case for loose smut as the fungus is within the seed.
"Due to this, good coverage at application is particularly important when treated for loose smut."
