(Aug. 28) Acquisition speculation is again swirling around Cincinnati-based Kroger Co.

The latest talk on Wall Street is focusing on published newspaper reports in Colorado, Texas, Utah and Ohio, as well as business publications such as the Bloomberg News, about a possible marriage between Kroger and Boulder, Colo.-based Wild Oats Markets Inc., a natural-foods retail chain.

Kroger, the largest U.S. supermarket chain, has been involved in about 20 transactions valued at more than $12 billion in the past five years.

Kroger has made moves toward the natural-foods market in recent months. In April, for example, the chain expanded its Naturally Preferred label and made the natural and organic foods available nationwide.

Neither company was commenting on the speculation.

Nevertheless, shares of Wild Oats Markets were on the rise, closing at $12.30 Aug. 26, up from $11.10 at the end of the previous day’s trading. Its 52-week range was $6.98-13.20.

Kroger, meanwhile, fell 12 cents, to $18.83.

Kroger has 2,496 supermarkets and multidepartment stores in 32 states. Among its banners are Kroger, Ralphs, Fred Meyer, Food 4 Less, King Soopers, Smith’s, Fry’s, Dillons, QFC and City Market.

Wild Oats operates 101 stores in 25 states and British Columbia under the banners Wild Oats Natural Marketplace, Henry’s Marketplace, Sun Harvest and Capers Community Markets.