对ＤＮＡ分子标记鉴定蔬菜作物种子纯度的原理进行了分析。结果认为：鉴定种子纯度以ＲＡＰＤ技术为宜。ＲＡＰＤ标记鉴定常规品种种子纯度研究中，应选择目标品种Ａ的ＲＡＰＤ图谱中出现而其他常规品种（一般５～１０个为宜）中不出现的ＤＮＡ谱带作为鉴定纯度用的特异谱带；鉴定杂交Ｆ１品种时，应将母本有、父本无、Ｆ１有的ＤＮＡ谱带和母本无、父本有、Ｆ１有的ＤＮＡ谱带作为特异谱带，并且在实践鉴定中二者必须联合使用。 The principle of identifying the purity of vegetable seeds by DNA molecular markers was analyzed. The results showed that: It is appropriate to identify the purity of seeds by RAPD technology. RAPD marker identification of conventional varieties of seed purity studies should choose the target species A RAPD spectrum appears and other conventional varieties (generally 5 to 10 is appropriate) DNA bands used to identify the purity of the specific band; identification For F1 hybrids, the DNA bands of maternal, paternal, F1, and maternal, paternal and F1 DNA bands should be used as specific bands, and both must be combined in practice use.