SENATOR DEFENDS U.S. MANDATORY FARM CONTROL BILL Sen. Tom Harkin, D-Iowa, defended his controversial mandatory supply control farm bill and said U.S. farmers should be allowed to vote in a referendum whether they approve of the proposal. The Harkin proposal would set loan rates of 5.17 dlrs per bushel for wheat, 3.77 dlrs for corn and 9.32 dlrs for soybeans, all to be put in effect under strict controls on planted acreage reductions. Present loan rates are 2.28 dlrs for wheat, 1.92 for corn, and effectively 4.56 for soybeans. Also under the plan, the U.S. would seek a world market sharing cartel with the European Community and other exporting nations, to share-out export markets, Harkin said during the first of several Senate Agriculture subcommittee hearings examining farm programs. Harkin made the following claims in testimony on his "Family Farm Act." -- The mandatory control bill would increase farm income and reduce government spending on agriculture. -- Harkin said his policy of high price supports would not ruin U.S. agricultural exports as critics claim, but would increase overall revenue from exports. This would be done by seeking agreement among major exporting countries including the European Community on market sharing at agreed high prices. Sen. Christopher Bond, R-Mo., countered during the hearing that such a grain export cartel is not workable. -- Harkin acknowledged that higher commodity price supports would be passed onto consumers, but he said high food prices stem more from "gouging" by food processing companies than from high farm product prices. Harkin cited what he termed "excessive" net returns on equity over five years of 33.4 pct at Kellogg, 31.9 pct Monfort, 22.8 pct Nabisco, 22.8 pct ConAgra, 21.2 pct H.J. Heinz, 19.1 pct Ralston Purina, 17.2 pct Pillsbury and 16.7 pct Quaker Oats. -- Harkin said a "legitimate" concern about his bill would be the impact of higher prices on livestock producers. He said as a transition to the higher prices, he would allow livestock producers to purchase Commodity Credit Corp. grain stocks for three years. Thereafter, livestock farmers would benefit from a "predictable and stable" grain price, he said. -- Harkin said that under his policy approach farm participation would be no more "mandatory" than the current farm program. He said farmers now must participate in farm programs in order to receive credit for planting and to protect farm income.