Club Root continues to spread across the UK, aided by the wet conditions that exacerbate the disease and shorter rotations practiced by many growers to optimise farm output.
Club Root resistant varieties have proven the mainstay in mitigating the effects in affected areas, but it is crucial to vary the genetics used if the gain is to be maintained, warned Gary Jobling of Syngenta.
He highlighted that HGCA research and advice indicated that varietal resistance gave good control at most sites. “Where growers are selecting Club Root resistant varieties, it makes sense to include SY Alister in their choice. Growing different varieties from different breeding lines will help to spread agronomic risk,” he added.
Mr Jobling advocated that SY Alister was well suited to earlier sowing, which many growers have indicated they intend to adopt for the coming season - after the difficulties experienced with oilseed rape establishment last year. “This may especially be the case where growers are bringing uncropped land back into production and taking the opportunity to establish OSR early. However, early sowing could also increase any issues with Club Root infection.
“That will make resistant varieties even more important in the variety mix,” he advised. “SY Alister has strong early hybrid vigour to get crops well established, with a prostrate autumn growth habit. The growing points are effectively protected from damage by winter chill, as typically occurs where stems elongate in the autumn.”
Club Root is now recognised as widespread through western England and most of the OSR growing area of Scotland, however its impact is believed to being seen at lower levels across a far more extended area of the UK. Extensive soil testing is carried out by FERA and SRUC.
“In the past growers may have been reticent to select Club Root resistant varieties for fear of yield penalties,” according to Jobling.
“Now, SY Alister can give results on parity with conventional varieties in all situations, especially in the North. But where Club Root attacks, it will still maintain good yields, compared to losses of 50% or more from susceptible varieties.
“SY Alister offers a genetic solution for proven Club Root infested land and ‘at risk’ areas where disease may be depressing OSR yield performance.”
