种子纯度是种子质量的最重要因素。对于玉米自交系,纯度同样不失为第一位的指标,但对另一指标——扩繁世代数,亦应同时给予足够重视,尽量避免高世代扩繁。这是由玉米自交系本身特点所决定的:其一,玉米是典型的异花 Seed purity is the most important factor in seed quality. For maize inbred lines, purity also remains as the first indicator, but for another indicator, the number of expansion gene generations, sufficient attention should also be given to avoiding the expansion of the next generation as much as possible. This is determined by the characteristics of maize inbred lines themselves: First, corn is a typical cross-species