After nine months without a group publisher, Rodale Inc. promoted from within on Wednesday when it named Prevention publisher Mary Murcko to the position. The post had been vacant since December when MaryAnn Bekkedahl decamped for a Web start-up. Along with the new title, which also includes executive vice president, Murcko will oversee all ad sales and marketing for the company’s stable of eight health-centric magazines, which range from Men’s Health to Organic Gardening. Each title’s publisher will now report to Murcko, including Laura Petasnick, who will succeed her at Prevention. Petasnick had been associate publisher at the magazine since last year, when she joined on from Vogue.