Stock market investors seeking to capitalise on the boom in food and agricultural commodities may have left it a little late to sow their investments for a short-term harvest, sector analysts warn.

The surge in food prices over the past year has fuelled a spike in the shares of agriculture-related companies from tractor makers to fertiliser producers. But analysts now caution that stock valuations for some companies have reached over-ripe levels at a time when food prices are showing tentative signs of stabilising.