The Obama administration Thursday abandoned a proposal to restrict planting of genetically engineered alfalfa, the latest rule-making proposal shelved as part of the administration's review of burdensome" regulation. Agriculture Secretary Tom Vilsack's decision not to regulate alfalfa genetically modified to survive applications of the Monsanto Co. herbicide Roundup is a victory for the big seed and agri-chemicals company and the American Farm Bureau Federation. The Obama administration said earlier this month it is reviewing all proposed government regulation to weed out proposals that are overly burdensome to businesses-part of a broader effort to repair relations with employers and industry. The administration has also shelved two proposed workplace-safety rules opposed by business. Alfalfa is raised as hay on about 20 million acres, making it the fourth-biggest U.S. crop by acreage. Only about 250,000 acres of alfalfa is raised organically, however. Some biotechnology officials have predicted that U.S. farmers will use genetically modified seeds to grow half of the nation's alfalfa. The vast majority of the nation's corn, soybeans and cotton are grown from genetically modified varieties.