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一、发展简况建国以来,北京郊区的玉米品种有很大发展。拿推广品种来说,五十年代推广优良农家种;六十年代推广双杂交种;七十年代推广单杂交种。各个年代的当家品种,主要推广种以及产量等详见表1。
First, the development profile Since the founding of the PRC, Beijing suburbs of corn varieties have great development. Take the promotion of varieties, the promotion of fifties fine farm families; promote two-hybrids in the sixties; seventies promote single hybrids. Table 1 shows the varieties, main varieties and yield of each species in each era.