The CBOT was mixed Tuesday with wheat leading the way higher overnight but with the day session seeing increased weakness in grains while oilseeds rallied. Chinese buying is rumored to be underpinning the soy complex, but no fresh daily export sales announcements have been made. Canadian and European rapeseed futures were firm or posted new highs but the quickening seeding in Brazil is keeping soybean rallies muted.  Fundamental news remains light and weather trends are broadly favorable for the U.S., Europe, and South America. The La Nina in the Pacific Ocean is strengthening but has yet to significantly disrupt South American weather patterns. Recall that this time last year Argentina was already struggling with drought that would s...