US soyabean futures jumped Friday as forecasters warned that unfavourable dryness will persist in Argentina, increasing stress on crops in the world's No 3 soyabean exporter. At 11:38 am CST, soyabeans for January delivery were up 12-1/4 cents, or 1.1%, to $11.24 a bushel at the Chicago Board of Trade. Corn for March delivery gained 5 cents, or 0.9%, to $5.84 a bushel. Wheat for March delivery edged up 4 cents, or 0.7%, to $5.83 1/4 a bushel.