摘要： 模仿育种是一快速、高效、针对性强的（改良）育种方法，但是根据最新国际保护公约规定，所育品种属于依赖性派生品种，侵害了原品种权人的权利。改良品种与原品种的遗传差异多大才算是依赖性派生品种，目前国内外没有标准。以BA为母本，以H28、昌7-29、502、P138、齐319、连87、吉853、京2101、京343、京832为父本组配了10对同母异父玉米杂交组合，研究了杂交组合两两之间的遗传差异。结果表明：遗传差异在20%以下的组合，父本之间具有明确的血缘关系；遗传差异在20%~30%的组合，父本之间有40%具有血缘关系，没有血缘关系的占60%；遗传差异在30%以上的组合，父本之间全部没有血缘关系。无论两父本之间是姊妹系，还是其中一个父本是用另一个父本回交2次改良而成，用它们组配的杂交组合之间的遗传差异都在10%以上。通过回交3次改良的组合，与原组合之间的遗传差异在10%以下。因此，将遗传差异小于10%作为判断是否是依赖性派生品种的DNA指纹鉴定标准。

关键词: 玉米, 依赖性派生, DNA指纹, 标准

Abstract: Ten hybrids crossed with the inbred line BA as the same female,and with H28,Chang7-2,9502,P138,Qi319,Lian87,Ji853,Jing2101,Jing343,Jing832 as different male parents.Using DNA fingerprint to analysis the genetic difference among these hybrids.The result showed:if the genetic difference between two maize hybrids is less than 20 per cent,then the two male parents have the same germplasms.If the genetic difference is between 20 per cent to 30 per cent,40 per cent male parents have the same blood relationship.When the genetic difference is more than 30 per cent,no male parents have the same consanguinity.No matter two inbred lines were sibling,or one inbred line comes from another by back cross less than two times,with these inbred lines as different male parents cross with one same female parent,the genetic difference between the two hybrids is more than 10 per cent.If one hybrid comes from another hybrid by back cross more than three times,the genetic difference between them is less than 10 per cent.So the number 10 per cent of the genetic difference between tow hybrids was regarded as the criterion to identify derived maize variety.

Key words: DNA fingerprint, Derived, Maize variety, Criterion

中图分类号: 

• S513