Wheat futures prices rose Tuesday on global weather concerns, from flooding in western Canada to dry weather in the Europe and U.S., which threatened to damage winter crops.

July wheat rose for the third day, gaining 8.25 cents, or one per cent, to $7.9875 US a bushel by late afternoon on the Chicago Board of Trade.

It jumped 4.1 per cent Monday. Wheat prices have gained 64 per cent over the last 12 months.

On Monday, the Canadian Wheat Board said fields are so wet that only three per cent of grain has been sown, compared with 40 per cent normally by this time of year.

The same day, the U.S. Department of Agriculture reported that about 42 per cent of the American winter wheat crop was rated poor or very poor in the week ending Sunday, up by eight per cent from the same period in 2010.

Drought has affected wheat crops from Kansas and France to Western Australia and China.

The U.S. is the world's largest exporter of wheat. Canada holds second place, with annual exports averaging almost 14 million tonnes.

The concern came less than a year after Russia banned grain exports until at least July 1, after the worst drought in 50 years. The ban pushed world food prices higher.

China, the world's biggest consumer and producer of wheat, also suffered drought last year.   The United Nations says global food costs advanced in April for the ninth time in 10 months