(March 5) It’s a common practice during a time of war: Two rival nations become allies to achieve a common goal. The same scene is playing itself out in the retail world.

The “nations” in this case, Whole Foods Market Inc. and Wild Oats Markets Inc., have the common goal of increasing the sales of organic food and other products.

The scenario has been a trend among retailers for years. Consolidation has created mostly larger and stronger retail chains able to survive and squelch the competition. It was only a matter of time before the two largest organic retailers realized the need to join forces.

Just last year, Wal-Mart Stores Inc., Bentonville, Ark., announced an initiative to expand its organic offerings and keep them at the chain’s “everyday low price.”

Other conventional retailers also are increasing their organic categories in an effort to lure customers from the likes of Boulder, Colo.-based Wild Oats or Austin, Texas-based Whole Foods, so the consolidation of the two chains just makes sense.

Completion of the Whole Foods purchase of Wild Oats, estimated to be worth $565 million, is expected in April. Then, Whole Foods plans to convert stores operating under the four Wild Oats banners into Whole Foods stores.

While the venture makes great business sense for Whole Foods and should bring about a stronger, larger chain with which to further the organic cause, it’s not necessarily good news for organic food consumers, who will have one fewer chain devoted to their lifestyle.

But if the organic food market maintains its strong growth, don’t be surprised to see more challengers to Whole Foods’ organic retail model.