September corn was down 2 cents at $5.84-1/2 per bushel, new-crop December was up 1-1/4 at $6.05-1/4. Turned mixed by midday. Sell-off in wheat weighs but market underpinned by fears that dry US Midwest weather may trim production. US Midwest crop belt will be mostly dry this week, adding stress to filling corn and soyabeans.