目前面对强大的国际竞争对手,迫切需要我们的种业迅速提升科技创新能力,增强国际竞争力。这也是我们建设现代种业的必由之路。进入21世纪,利用杂种优势选育和推广优良杂交种一直是世界各国玉米科研的主流方向,在玉米杂交种优势利用上相继经历了品种间杂交种、双交种和单交种三个发展阶段。我国从20世纪50年代开始推广利用玉米杂交种,经过大约10年的时间, In the face of a strong international competitor, we urgently need our seed industry to rapidly upgrade our technological innovation capability and enhance our international competitiveness. This is also the only way we can build modern seed industry. Into the 21st century, the use of heterosis breeding and promotion of excellent hybrids has been the mainstream of corn research in all countries in the world, the advantages of utilization of maize hybrids have undergone three varieties of hybrids, double cross and single cross three stages of development . Since the 1950s, China started to promote the use of maize hybrids. After about 10 years,