* Cold weather across key producing region threatens crops
* Soybeans fall from two-week high; corn also lower
SYDNEY/PARIS, Dec 28 (Reuters) - U.S. wheat futures fell on Thursday after posting gains of more than 1 percent in the previous session, though the drop was limited by ongoing concerns about potential crop losses from recent cold weather across the United States. Soybeans were also down, retreating from a near two-week high touched in the previous session, while corn edged lower. The fall in grains was also slowed by a weaker dollar, making them more competitive on world markets. The most active wheat futures on the Chicago Board Of Trade were down 0.5 percent at $4.26 a bushel by 1200 GMT, having closed up 1.4 percent on Wednesday. Despite the drop, traders said prices remain supported by concerns over potential yield losses as cold weather lingers across the U.S. Plains. "Activity is light and we are seeing some squaring after last night, though losses are limited by the potential adverse weather in the States," said one Melbourne-based trader. Investment funds were holding a near record net short position in U.S. wheat futures and had sizeable net shorts in corn and soybeans, according to regulatory data released last week. The most active corn futures fell 0.2 percent to $3.53 a bushel, having gained 0.3 percent in the previous session. The most active soybean futures were down 0.4 percent to $9.63-1/2 a bushel, having closed down 0.3 percent on Wednesday after earlier hitting a high of $9.76 a bushel - the highest since Dec. 14. Soybeans have drawn support from concerns that dry weather conditions in some parts of Argentina may curtail production. However, recent rains in the central Pampas grains belt are expected to improve soil moisture and allow producers to advance with plantings of soybeans and corn, which had been delayed due to dry weather, agricultural analysts said. An explosion at a port operated by Chinese export company COFCO in Argentina's Rosario grains hub killed one person dead and injured others, local authorities said. It was unclear how the incident would impact operations at the port.
Prices at 1200 GMT
Last Change Pct End Ytd Move 2016 Pct
CBOT wheat Mar 426.00 -2.00 -0.47 408.00 4.41 CBOT corn Mar 353.00 -0.75 -0.21 352.00 0.28 CBOT soy Mar 963.50 -4.00 -0.41 1004.00 -4.03 Paris wheat Mar 159.25 -0.25 -0.16 177.50 -10.28 Paris maize Jan 154.25 0.25 0.16 166.00 -7.08 Paris rape Feb 348.25 -2.25 -0.64 380.25 -8.42 WTI crude oil 59.62 -0.02 -0.03 53.72 10.98 Euro/dlr 1.19 0.00 0.41
Most active contracts - Wheat, corn and soy US cents/bushel, Paris futures in euros per tonne
(Editing by Kenneth Maxwell and David Evans)