沈单7号玉米是全国推广面积最大的春播品种。但在制种上结实较少，产量较低是多年来制种技术的一大难题。沈单7号玉米制种结实较少，除特殊的自然条件影响外，父母本花期相遇的好坏有直接的影响。卢龙县种子站在几年的沈单7号制种过程中，通过试验观察进行花期技术调节，达到花 Shen No. 7 corn is the largest popularized area of ​​spring sowing varieties. However, less seed production, lower yield is a major problem in seed production technology over the years. Shen No. 7 maize seed less robust, in addition to the special natural conditions, the parents of the flowering period has a direct impact on the quality. Lulong County seed stand Shen several years on the 7th seed production process, through the experimental observation of flowering technology regulation, to spend