World wheat prices surged again this week on renewed concerns about the impact the weather is having on crops in the US, China and Europe.
Risk manager Agritel raised concerns that spring crops in some parts of northern Europe were now thought to be at risk.
Wet weather in the US corn belt is preventing maize being planted. In other parts of America drought is the problem. Hard red winter wheat in the plains has suffered from poor growing conditions since it was sown last autumn.
Wheat crops in northern China are also under stress from dry weather. Speculation is growing they may require to be irrigated to prevent yield loss.
Also helping markets was Russian agriculture research and consulting organisation SovEcon which said it was unlikely Russia would lift its ban on grain exports before July, quashing rumours the Kremlin was considering an earlier lifting of the ban – imposed last August in response to drought and wild fires which hit grain production.
Wheat prices in London for May closed up £5.50 a tonne at £212.50, while new-crop November rose £6.25 to £170.75. November 2012 benefited too, increasing £6.50 to £155.50.