Thailand's Suwannapura had just one blemish in her opening round of 66, dropping a single shot on the seventh but carding seven birdies to more than make up for the disappointment.
Derrey of France performed even better, posting a flawless round to join Suwannapura at the top of the scoreboard in pleasant sunny conditions at the Delhi Golf Club.
American Hannah Jun had earlier set the clubhouse lead but eventually finished the day two shots off the pace after a four-under 68.
Starting on the back nine, Jun mixed one birdie with one bogey on her opening nine holes but four birdies on the return fired the 28-year-old up the leaderboard.
Tour rookie Charley Hull is also in the mix thanks to an opening round of 69, just three shots off the leaders.
The 17-year-old Englishwoman sank four birdies, with a dropped shot on the par-four 13th her only error, and Hull was more than satisfied with the start she had made.
"I hit it pretty good," she told the Ladies European Tour website.
"I didn't hit it that well in the practice rounds and on the range it was the worst I've ever hit it in my life but I went out there and flushed it again, so I'm feeling pretty happy with my game.
"All in all my game was pretty good. I made a birdie on 17, hit an iron shot to six feet but missed a seven-footer at the last, so a bit disappointed about that.
"Overall I'm happy because three under on this course is good."
Hull's compatriot Danielle Montgomery is six shots off the lead after opening her challenge with a level-par 72.