Autumn Drought Demands Extra Take-All Care

September 2003 - The prolonged autumn drought means much of the 2004 UK wheat crop will require particularly careful take-all management this season, warns ProCam Agronomy. And this extends to wheats after set aside and spring barley as much as to second wheats.

"High soil temperatures, inadequate volunteer and grass weed control, dry stubbles, and less-than-ideal seedbeds all increase take-all risk," pointed out technical director, Dr David Ellerton. "As does anything that adversely affects the speed of crop establishment and extent of early rooting.

"So once we actually get some decent rainfall we'll have everything but the kitchen sink as far as take-all risk is concerned this autumn.

"Soil temperatures are continuing to stay high. Little or no significant straw or stubble breakdown since harvest means considerable disease carryover from infected crops. Grass weed populations have been notably high over the past season, and increasingly serious time constraints will mean relatively poor pre-planting control of these and cereal volunteers in many cases. What is more, seedbed preparation is set to be both difficult and rushed.

"Add to this increased seed rates to compensate for poorer seedbeds and insufficient consolidation of dry soils containing relatively large amounts of poorly decomposed straw and you have just the right conditions for serious take-all damage."

Under these circumstances, Dr Ellerton stresses that wheat growers need to do everything possible to combat the disease this autumn if they are to avoid serious 2004 yield and quality losses.

He explains that second wheats sown before mid-October into light, sandy or organic soils are at greatest risk. However, he warns that good take-all management must also be a priority in wheats after set aside, especially if early-sown, and on poorly-structured clay soils which both favour infection and restrict rooting.

"Positive take-all management will be more essential for more growers than ever in the coming few weeks," insisted David Ellerton.

"Wherever take-all is a threat the first essential is to protect your seed with a specialist take-all fungicide. With cereal prices set to remain healthy this will be a particularly cost-effective insurance.

"Then, make sure you really consolidate your seedbed well. Firm seedbeds restrict the spread of the take-all fungus. By preserving soil moisture and improving soil/seed contact they also encourage rapid establishment and rooting, allowing the seedlings to tolerate higher levels of root damage.

"Press well immediately after cultivating; especially if you're ploughing. And roll effectively as soon after drilling as possible," David Ellerton advised.

"Finally, wherever possible, avoid rushing into drilling without good pre-planting volunteer and grass weed control, and the best possible seedbeds. And remember too that take-all risk declines markedly as drilling moves into mid-October."