Watch ratings for resistance
DISEASE resistance scores for winter wheat are being ignored by most farmers. Yet it is one of the main factors growers should consider to improve crop management and economic returns.
"When we looked at the amount farmers spent on fungicides on resistant and susceptible varieties, the difference was absolutely zero," said cereal plant pathologist Neil Paveley at ADASs Crop Centres Conference in Peterborough last week.
"Despite all the effort from the breeders, growers were not exploiting the opportunities that genetic resistance was offering."
Two other factors, inoculum and weather, also governed disease progress, he said. Whatever the variety, growers could save further expense by not panicking too early in the season.
The amount of inoculum on a plant in early spring had little effect on future levels, he stressed. Severe disease was no worse than a little (less than 1%) in influencing future disease epidemics. So growers should not panic provided they applied a fungicide by GS32, when the third leaf was emerging.
Timing and rates could be varied successfully provided a few simple rules were followed. Septoria needed to be treated 7-10 days after each of the top three leaves had emerged; yellow rust just after emergence.n
Cereal growers are throwing money away by ignoring disease resistance ratings, says Neil Paveley.