Farm expert joins Politburo

Mikhail S. Gorbachev, a 49-year-old agricultural specialist, was elected to the Soviet Communist Party's ruling Politburo, becoming by far the youngest member of the effective Kremlin cabinet. The elevator of Mr. Gorbachev to the top ranks of the leadership was seen as a sign of Kremlin determination to come to grips with the apparently growing problems of the country's agriculture system.

He was brought to Moscow from the grain-growing Stavropol region only two years ago to become the Central Committee's secretary for agricultural affairs. His sudden rise from relative obscurity and his youth mark him as a good candidate for an eventual top post in the hierarchy.

Mr. Gorbachev's elevation comes amid growing signs that this year's grain harvest will be extremely disappointing for the leadership, which had set a target of about 260 million tons. Soviet agricultural sources have predicted the actual harvest at about 200 million tons.

The Central Committee session came on the eve of a meeting of the Supreme Soviet, or parliament, which is due to approve the economic plan and budget for next year.