BY NANCY SAN MARTIN

  As Cuba's state security officers picked up scores of dissidents and threw them in jail in March, U.S. food and agricultural sales to the island continued at a brisk pace.

 The arrests led to worldwide condemnation of Fidel Castro's government, but they did not disrupt the flow of exports, even as some trips to Cuba by business executives and anti-embargo delegates were put on hold.

  The value of U.S exports for March, the most recent data available, totaled an estimated $18.2 million -- about $17.5 million of it reported as agricultural products -- according to figures released this week by the U.S.-Cuba Trade and Economic Council, a New-York based group that tracks Cuba's economy.

  The March figures were 121 percent higher than during the same period a year ago. Export figures for April, when harsh sentences were issued against 75 Cuban
  dissidents and three ferry hijackers were executed, are not yet available.

  Shipments, however, are expected to continue to swell, with total sales for 2003 projected at about $166 million, a 19 percent increase over last year's.

  ''Exports are on track,'' council president John Kavulich said. ``There is no indication, as yet, that the fluctuations in food and agricultural purchases by Cuba have been impacted by noncommercial reasons.''

  Since shipments to Cuba began in December 2001, total sales of food and agricultural products to the island have been valued at more than $187 million, making Cuba an increasingly attractive export market for U.S. companies.

  The direct commercial exporting of food products is allowed under the Trade Sanctions Reform and Export Enhancement Act, which requires that the transactions be on a cash basis.

  Some analysts point to agricultural sales as an example of solid bilateral relations, despite heated verbal exchanges between U.S. and Cuban government officials and the recent ouster of 14 Cuban diplomats accused of engaging in espionage. All 14 have left the United States, U.S. officials confirmed Thursday.

  ''The relationship is remarkably stable on core issues,'' said Jorge Domínguez, author and Harvard University expert on Cuba. ``The building blocks either haven't changed or have gotten better under the Bush administration.''

  In addition to the increase in sales, other ''building blocks'' cited by Domínguez as examples of stable bilateral relations are the ongoing amicable relationship between military officials on the Guantánamo Naval Base and their counterparts in Cuba as well as the continued cooperation between the U.S. Coast Guard and Cuban authorities in drug-interdiction efforts and repatriations.

  ''All the big items haven't been touched,'' Domínguez said.

  Underscoring a continuing desire among some for closer relations with Cuba was a visit to Havana this week by Rep. Leonard Boswell, a Democrat from Iowa who headed a delegation of several dozen farm representatives.

  Boswell announced $4 million in new U.S. farm sales to Cuba and -- echoing dozens of other recent American visitors to the island -- called for an end to the United States' trade and travel restrictions.