Strong world demand, combined with higher energy and raw material costs, have pushed up agrochemical prices by 7-10% this autumn compared with last, say industry sources.

Many say demand for chemicals rose worldwide on the back of last year's high wheat prices and increased acreages, added to by land coming out of set-aside. Land coming into full production in eastern Europe required a fairly heavy chemical input, adding particular pressure to European product availability.

For some products, supply was relatively tight, as 10-15 years of manufacturers' streamlining processes meant there was less flexibility in the industry to produce extra product at short notice.

Glyphosate had more than doubled in price since autumn 2007. But with many growers having stocked up on the product before the recent price rises, Anglia Farmers' Nigel Last said there was no rush to buy in anticipation of further rises. "There is plenty of stock in store and we've seen prices ease a bit over the last six to eight weeks."

Some steam had been taken out of the price rises by uncertainty over growers' plans for next season. John Humphreys, arable products manager at AtlasFram, said all products were available and where the price might be too high for some because of tight supplies, there would be cheaper alternatives readily available.

"For example, Proline [prothioconazole] and Liberator [flufenacet + diflufenican] are tight, but there are alternatives, so growers do not need to pay inflated prices."

The market for diflufenican was competitive, and some even reported a price drop compared with last year.

Another factor working against autumn herbicide price rises in the short-term was the relatively large stocks of IPU thought to be held on-farm, which must be used by 30 June 2009. The potentially late season could also mean that the optimum timing for some products would pass before they could be used.