This leader received the “Letter of three hundred” from scientists decrying a decline in biology research. This leader had Machine-Tractor Stations rapidly closed and forced farmers to buy the leftover equipment. A visit to the Iowa (10[1])farm of Roswell Garst inspired this (10[1])leader (10[1])to grow new hybridized (10[1])corn breeds in his country, (10[1])which (10[1])largely failed due to climate (10[1])differences with the US. This leader recruited Komsomol volunteers to move to new farms in the Virgin Lands program. At the 20th Congress, this leader gave a speech titled “On the Cult of Personality (10[1])and Its Consequences” that denounced his predecessor (10[1])and signaled the beginning of a relaxation of censorship called this leader’s “Thaw.” For 10 points, what Soviet leader gave the “Secret Speech” and succeeded Joseph Stalin? ■END■