A scorching hot, dry summer has ended five years of plenty in many wheat producing countries and drawn down the reserves of major exporters to their lowest level since 2007-08, when low grain stocks contributed to food riots across Africa and Asia.

Although global stocks are expected to hit an all-time high of 273 million tons at the start of the 2018-19 grain marketing season, according to U.S. Department of Agriculture estimates, the problem is that nearly half of it is in China, which is not likely to release any onto global markets.

Experts predict that by the end of the season, the eight major exporters will be left with 20 percent of world stocks — just 26 days of cover — down from one-third a decade ago.