WHEAT - Down 1/2 to 1 cent per bushel

Modestly lower on technical selling and better-than-expected weekly US winter wheat condition ratings. Market underpinned by excessive rains in the southern Plains and Midwest that threaten winter wheat yields and production.

The US Department of Agriculture late Monday rated 52 percent of the US winter wheat crop as good to excellent, up from 51 percent a week earlier. Analysts had expected a decline.

The USDA also said the US spring wheat crop was 90 percent planted, in line with expectations and ahead of the five-year average of 84 percent.

CBOT July soft red winter wheat was last down 1/2 cent at $4.33-3/4 per bushel, K.C. July hard red winter wheat last down 3 cents at $4.33 and MGEX July spring wheat last down 2-1/2 cents at $5.56-3/4.

CORN - Down 1 to 2 cents bushel

Light profit-taking setback after a two-session climb tied to worries about re-planting due to excessive rains in portions of the Midwest. Most-active July corn retreated back below its 100-day moving average in early moves.

The USDA said the US corn crop was 84 percent planted, slightly behind trade expectations and the five-year average of 85 percent.

Heavy rains this week brought relief to parched fields in China's major grain producing regions, breaking a months-long dry spell that had slowed corn planting and hit winter wheat crops.

CBOT July corn was last down 1-1/4 cents at $3.73-3/4 a bushel.

SOYBEANS - Down 2 to 3 cent cents per bushel

Lower on technical selling after a two-session advance and slightly better-than-expected US planting progress.

The USDA said private exporters sold 126,000 tonnes of US soybeans to unknown destinations for delivery in the 2016/17 marketing year that began Sept. 1.

The USDA late Monday said the US soybean crop was 53 percent planted, slightly ahead of trade expectations and the five-year average of 52 percent.

Malaysian August palm oil futures fell 1.47 percent, weighed down by a stronger ringgit currency and forecasts of rising production.

CBOT July soybeans were last down 3 cents at $9.53-1/2 per bushel.