It is entirely possible that  Argentina's peso could decline 25 percent from the current official exchange rate by the end of 2015. If so, that country's grain sales could become extremely active in the January-February period.Improved weather prospects are enabling Brazilian farmers to plant their soybeans, but there generally seems to be a lack of interest in marketing activities because of a common expectation that future exchange rates will soon become even more advantageous. Of course there is always a potential danger that any common hope that turns into a uniform expectation can instead become a widespread disappointment. Nevertheless, current sales activities in the Brazilian soybean market are virtually nonexistent.Chinese buy...