热带、亚热带外来玉米种质的利用

Utilization of exotic tropical and subtropical maize germplasm

我国近几年平均每年种植玉米 2 45 0万公顷 ,平均产量为每公顷 4 96吨 ,种植面积和总产量居世界第二位。但 70年代以来我国玉米增产率呈下降趋势 ,玉米生产一直处于徘徊状态 ,其主要原因是国内种质资源匮乏 ,缺乏新的杂种优势群和杂种优势模式。分析热带、亚热带外来玉米种质在我国玉米育种中的作用后 ,指出利用玉米起源中心的热带、亚热带种质可以拓宽温带种质的玉米遗传基础 ,构建新的杂种优势模式 ,产生出超强优势的杂交玉米新组合 ;提出了热带、亚热带外来玉米种质的利用途径及方法。

Maize is the third most important crop in the world and China.The average of maize production area in China is 24 5 million ha;the average maize yield is 4 96 ton per ha China ranks the second in the world in terms of total maize area and production.The rate of maize yield growth has being declining due to narrow genetic background and limited new heterotic patterns since 1970s.The role of tropical and subtropical maize germplasm in maize improvement was discussed in this paper.It was concluded that the Chinese maize germplasm background should be broaden by using the tropical and subtropical maize germplasm.The new heterotic patterns should be developed and new hybrids with super heterosis could be bred,the methods of using tropical and subtropical maize germplasm were pointed out in this paper.