Allied Grain's second wheat performance trials at Haywold
22/03/05

Take-all levels this spring are the highest for the past three years, according to early season root assessment results from Allied Grain's second wheat performance trials at Haywold in Yorkshire.

Involving 10-14 varieties grown as second and subsequent wheats on the same site to the same protocols, these trials provide an excellent basis for monitoring take-all incidence over the years.  Especially so since they involve earlier and later drillings made with or without the same take-all seed dressing at the same time each year, almost to the day.

“Over the past three years we've drilled our earlier Haywold trials consistently between September 12th and 16th and our later ones between October 1st and 2nd,” explained Allied Grain Trials andTechnical manager, Jim Carswell. “We've also been consistent in sampling roots for early take-all levels between March 5th and 10th to make comparisons between seasons as valuable as possible.

“This year's results suggest we could be in for a particularly damaging take-all year,” he pointed out. “Without a specialist take-all seed treatment, indeed, our early drilled trials had an average Take-all Index of 16, while the later drillings averaged 8. In both cases, these are the highest levels we've recorded in recent years.

“As we've come to expect, infection levels were markedly lower across the Latitude (silthiofam) treated plots. But again the indices were higher than in the past three seasons.”

Allied Grain Haywold 'Second Wheat' Trials - Early Season Take All Indexes

Jim Carswell attributes the high level of current root infections to the mild and persistently moist soil conditions of the past winter. He points out that while his records show a lower than average winter rainfall at Haywold, they also reveal there has hardly been a day on which the site has not received some rain.

“From October through to the spring, our crops have sat in damp soil,” he observed. “This and the mild weather has been just the ticket for the take-all fungus.

“We didn't see a high level of take-all damage last year. But this was mainly because the wet summer allowed crops with impaired root systems to survive relatively well.  This year, the build-up of infection will be further encouraged when temperatures warm up in spring and could prove highly detrimental for crops encountering moisture stress over the summer.

“We simply cannot afford to let down our guard as far as take-all is concerned, “Jim Carswell concluded.  “While there is relatively little that can be done at this late stage, I would advise growers who haven't treated their second wheats with a specialist take-all seed treatment, in particular, to do everything possible to encourage  root development and discourage the disease in the next few weeks. This means taking special care with fertilisation and T1 fungicide choice.”