by Beth Kowitt, writer-reporter

DuPont’s stellar stock performance has been driven in large part by its investment in research and development during the downturn, said Ellen Kullman, the company’s CEO, during Fortune’s Most Powerful Women’s Conference on Tuesday.

The stock is up more than 30% this year, leading all other stocks in the Dow Jones Industrials index, said Fortune’s Carol Loomis, as she kicked off her interview with Kullman. One of the keys to the jump: DuPont (DD) had 60% more new products in 2009 than in 2008, said the 22-year DuPont veteran. “We see that the changes in the world really are asking us to innovate at a faster rate,” Kullman said.

The company has a 200-year history of innovation, but Loomis questioned whether its rate of development of blockbuster products has slowed in the last half century after the launches of products like Tyvek, the ubiquitous synthetic fiber. “I’d like to think we’ve had a lot since then,” Kullman said. She noted that while Kevlar came about more than 40 years ago, the Kevlar of the past looks nothing like it does today.

To help drive innovation, DuPont is taking a global approach. The company now has 70 research centers around the world. Kullman also said the company has changed how it staffs its business internationally. It once filled its offices overseas with Europeans and Americans who grew up in DuPont, but the company now focuses on growing local successors. The head of China is from China, she noted, not from America. This staffing strategy turns the company into a better employer and recruiter, and allows locals to see better opportunity from a multi-national.

DuPont is on firm footing, but Kullman admitted that during the financial crisis the unprecedented degradation in business was frightening. The company is now hiring again, but it laid off 4,000 and sent home 10,000 contractors amid the downturn. “There was a little bit of terror there,” she said.