推广玉米双杂交种,是利用杂种优势提高玉米产量的一个有效措施。繁育双杂交种的特点是每年必须成套的,按比例的繁殖亲本自交系、配制单杂交种和双杂交种,才能提供大面积的生产用种。同时在繁殖配种过程中,必须充分注意亲本的保纯和杂交貭量,不然就会因为自然杂交降低它的增产作用。所以要想使玉米双杂交种在生产上迅速 Popularizing two-hybrid corn is an effective measure to increase the yield of corn by using heterosis. Breeding two-hybrids is characterized by the annual must be complete, the proportion of breeding parental inbred lines, preparation of single hybrids and two-hybrids in order to provide large-scale production of species. At the same time in the breeding and breeding process, we must pay full attention to the purity of the parent and the amount of hybrid, otherwise it will reduce its yield because of natural hybridization. So to make corn two hybrids in production quickly