MOSCOW  Viktor A. Semenov was growing lettuce on a collective farm outside Moscow in 1990 when a representative of McDonald’s stopped by. The company had just opened a restaurant. Could he sell it a few boxes of lettuce each week?

Mr. Semenov’s assistant turned it down. One restaurant was too small an order.

“I said, ‘My friend! You see how many McDonald’s there are in the West?’ ” Mr. Semenov recalled recently. “I said, ‘Sell them lettuce at any price. It’s our new strategy.’ ”

With that, Mr. Semenov started a company that has all but cornered the market on packaged fresh vegetables in Russia.

With a buy-one-get-one-free deal on hamburgers and a traditional Russian accordion band, McDonald’s celebrated on Monday the 20th anniversary of the opening of its first store in the Soviet Union, a restaurant that drew long lines.