The Reagan administration's long-awaited farm bill went to Congress yesterday, but without proposals for a food stamp program that historically has been linked to general farm legislation.

A Department of Agriculture spokesman explained that separation of the two programs was deemed necessary because Congress may not finish work on the general farm bill until late summer -- too late to allow food stamps to be dealt with in the congressional budget reconciliation process.

"We envision some savings in this fiscal year in food stamps," said Randy Russell, an aide to Secretary John R. Block, "and we thought it important to have action on food stamps as soon as possible."

Farm and nutrition experts disagree on the importance, if any, of a legislative link between the general farm bill and food stamps, although it is generally believed that urban legislators have been more inclined to support the farm programs in return for rural support on food stamps.

This year, the first time the two programs will be dealt with under the congressional budget procedures, the linkage is seen as less significant. The food stamp program's financing will be dictated largely through the budget committees.

The administration's budget proposals envision savings of $1.2 billion with food stamp cutbacks in fiscal 1982. The Senate Budget Committee is shooting for savings of $1.4 billion; the House committee, voting yesterday, for $1 billion in program reductions.