Canadian fertilizer maker Agrium Inc , reported a surprise quarterly loss on Thursday as it grapples with low fertilizer and crop prices, and also cut its full-year profit forecast.

U.S. farmers are cutting back on spreading fertilizer this autumn in response to a drop in crop prices to multi-year lows and a delayed harvest, dealers say, warning of a pullback that will be felt from grain markets to Canadian potash mines.

Agrium cut its full-year profit forecast to $4.60 to $5 per share, from the prior range of $5 to $5.30 per share.

In September, Potash Corp of Saskatchewan Inc and Agrium agreed to join forces in an all-stock deal that will allow Potash shareholders to own 52 per cent of the new company, with the rest going to Agrium shareholders.

Shareholders of both companies are scheduled to wrap up voting later on Thursday, and they are expected to back the merger.

Agrium reported a net loss from continuing operations of $39 million, or 29 cents per share, in the third quarter ended Sept. 30, compared with a net profit of $99 million, or 72 cents per share, a year earlier.

On an adjusted basis, Agrium posted a loss of 12 cents per share. Analysts on average had expected earnings of 11 cents per share, according to Thomson Reuters I/B/E/S.

Total sales fell by about 11 percent to $2.25 billion.