CBOT wheat down as harvest outlook improves

May 8 (Reuters) - Chicago Board of Trade wheat futures closed lower on Thursday on improved harvest prospects for wheat in the U.S. Plains and spillover weakness from corn futures, traders said.

• Rains over the U.S. Plains have delivered much-needed moisture to the wheat crop and have boosted yield expectations.

• Traders are also positioning ahead of Monday's U.S. Department of Agriculture's monthly supply and demand report.

• The U.S. Department of Agriculture (USDA) said net old-crop U.S. wheat sales totaled 69,700 metric tons in the week ended May 1, in line with trade estimates. New-crop sales rose to 493,000 tons, above trade expectations. EXP/WHE

• Canadian stocks of wheat as of March 31 were down 1.2% from a year earlier at 15.4 million metric tons, according to a farm survey by Statistics Canada released on Thursday.

• CBOT July soft red winter wheat WN25 fell 5 cents to $5.29-1/4 per bushel.

• K.C. July hard red winter wheat KWN25 ended 4-3/4 cents lower at $5.24-3/4 per bushel.

• Minneapolis July spring wheat MWEN25 ended 2-1/4 cents lower at $6.00-3/4 a bushel.