Gwladys Nocera of France missed an eagle opportunity on the 18th that would have tied the Koreans. Canada shot 64, a stroke ahead of the United States, Philippines and Sweden in the two-player team event featuring 20 countries.
The South Korean pair of Ji-Yai Shin and Eun-Hee Ji had set their sights on shooting 8-under for the opening round of best-ball play at the 6,466-yard Gary Player Country Club.
'When we got six birdies in the first nine, we looked at it again, and just went as low as we could,' Ji said.
The French pair of Nocera and Virginie Lagoutte-Clement finished with 10 birdies, and Lorie Kane and Elena Sharp led the Canadians.
The U.S. reached the turn in 4-under 32, with Juli Inkster and Pat Hurst picking up four birdies. They had three more on the back nine.
Defending champion Paraguay, Taiwan and Japan were five shots back.
Saturday's format features alternate-shot foursomes.
Nocera said the French pair was fading until a two-hour delay for lightning and a heavy rainstorm revived them.
'We were on the 15th, so it was good to get back to the clubhouse and have a cup of coffee before going out again,' she said.
After the break, they birdied the 16th and 18th
'I hit a 7-wood in to the green on 18 because I knew Virginie would get close to the pin with her third and have a definite birdie chance,' Nocera said.
Lagoutte-Clement obliged by leaving a superb third shot right on the lip of the cup, and Nocera missed her 20-foot eagle attempt.
With the fairways and greens soft after heavy overnight storms, the players were able to attack the pins, knowing that risky shots were worth playing. There were 120 birdies and two eagles posted by the 40 players.
Australia picked up the first eagle, at the 492-yard par-5 fifth. Lindsey Wright hit her second shot to within 15 feet of the pin over an intimidating bunker in front of the green and sank the chip from the edge of the green.