DALLAS — A new credit card deal and rising corporate travel boosted profits for Delta Air Lines in the first quarter, a trend it predicts will continue this spring.

Delta executives said Wednesday that corporate-account revenue is up 10 percent from this time last year, one of several factors that pushed Delta’s first-quarter profit up by 31 percent, to $730 million.

Delta’ also says its new credit card deal with American Express will produce $500 million in additional revenue this year.