Chicago wheat futures rose about 1 percent on Tuesday as a decline in US crop ratings and news of radioactive pollution in the Ural mountains triggered a round of short-covering and concern about wheat exports from Russia, the world's top supplier. Corn and soyabean futures were little changed in choppy trade.
As of 12:31 pm CST (1831 GMT), Chicago Board of Trade December wheat was up 4 cents at $4.26 per bushel after reaching $4.28-3/4, its highest in a week. CBOT December corn was steady at $3.45 a bushel after reaching $3.45-3/4, its highest since November 9. January soyabeans were down 1 cent at $9.89 a bushel.
Wheat firmed after Russia's meteorological service said it had measured pollution of a radioactive isotope at nearly 1,000 times normal levels in the Ural mountains. That marked the first official Russian data supporting reports that a nuclear incident had taken place in Russia or Kazakhstan in the last week of September.
Neither Russia nor Kazakhstan has acknowledged any accident. The Russian news reminded some traders of the Chernobyl nuclear disaster of 1986, which sparked a rally in CBOT grain futures. But many were skeptical about the market impact of the contamination, and attributed strength in wheat to technical buying.
Russia is the world's biggest wheat exporter, and its farmers just completed the harvest of a record-large crop. Wheat also drew support from the US Department of Agriculture's weekly crop conditions report late Monday. The government rated 52 percent of the winter wheat crop in good to excellent condition, down from 54 percent the previous week, despite analyst expectations for no change.
CBOT corn was nearly flat after pushing to a 1-1/2-week high. The USDA late Monday said the US corn harvest was 90 percent complete, behind the five-year average of 95 percent, while the soyabean harvest was 96 percent done, near the five-year average of 97 percent.