6 September 2002

Dressing can change roles

SOME winter wheat varieties performing relatively poorly against others in the second crop slot could see their reputations reversed with take-all seed treatment, latest Dalgety trials results suggest.

"The commonest question I was asked at our open days in July was: Which variety is best as a second wheat?" says Mike Jeffes, trials specialist at the firms Throws Farm in Essex.

Most growers realise that Equinox is not a good second wheat irrespective of seed treatment, notes Mr Jeffes. Many also regard Consort, not Claire, as a good choice in that slot. But take-all dressing can make a big economic difference to that picture, this seasons trials show (see table).

Neither take-all seed treatment, Jockey (fluquinconazole) or Latitude (silthiofam), is a panacea for the disease, he warns. "And on average we cant really differentiate between the two products in terms of take-all control."

Instead they should be used as management tools. So their interaction with six varieties, highlighted in the replicated Oct 13-drilled trials on chalky boulder clay, is a useful guide to where they might be most effective in a similarly bad take-all season, he believes.

Whiteheads were visible in the plots very early.

Unexpectedly Richmond, not on the Recommended List, turned in the best margin over seed treatment costs and did not merit take-all dressing. "It had a fantastic year," says Mr Jeffes. "Whether that performance was a one-off remains to be seen."

Option, gaining a reputation similar to Claires as a non-second wheat, also benefited from take-all protection, the treatments more than paying for themselves.

Oddly though Xi19 seemed to respond better to Jockey than Latitude. But Mr Jeffes says that cannot be because of any difference in controlling the mystery late season yellowing (Arable, July 12) often seen in this seasons crops. "We didnt get the problem here!"

Clearly treating Consort again-st take-all was uneconomic. &#42


Jockey Latitude Sibutol

+ Sibutol + Sibutol Secur

Secur Secur

Claire 481* 468* 447

Consort 463 454 468

Equinox 444 435 445

Option 501* 498* 485

Richmond 505 510 514

Xi19 488* 465 474

* = positive benefit from addition of take-all treatment.

Source: Dalgety Throws Farm.

Not all wheats will pay for take-all treatment, says Mike Jeffes.