GRAINS-Wheat rallies 3 pct on U.S. production fears

(Adds Ukraine news; updates prices) * Temperatures across Southern Plains soar * Corn edges down, soybeans firm By Colin Packham SYDNEY, May 5 (Reuters) – U.S. wheat futures rose as much as 3.4 percent on Monday to an 11-month high on fears that recent hot, dry weather will curb production in the United States, the