确实是玉米，红薯的引入中国后，中国人口才大幅增长，是因为这两种作物产量高，皮实。稻麦产量低，不好养。

来源: newnewid888 于 2014-04-22 18:38:15 [旧帖] [给我悄悄话] 本文已被阅读：次

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