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中国玉米种质资源少，只有远缘杂交才有可能获得遗传多样性。但是，远缘杂交Ｆ２的疯狂分离，使得一个优良性状的稳定往往需要经过多代选择，耗时费力。我们利用从孤雌生殖产生的纯合２倍体，仅２～３年即选育出了优良异源种质纯系５４０（Ｆｉｇ．１），而常规育种至少要５～６年。本工作选用ｚｉ３３０，旋９，ＭＯ１７，黄早４等自交系与远缘种属２倍体多年生类玉米（ＤＰ）杂交，将其Ｆ１的ＢＣ１去雄，在花丝上喷撒ＭＨ，ＤＭＳＯ，ＰＥＧ，诱导孤性生殖。纯系５４０的株高、穗位、穗长等农艺性状（Ｆｉｇ．３）优于ＤＰ（Ｆｉｇ．２），但其抗逆性优于亲本ｚｉ３３０。染色体分带结果：纯系５４０（Ｆｉｇ．６）的总带数为８，与亲本（Ｆｉｇ．４＆５）相同。但其Ｃ带特征，一方面，兼有二者的特点，如：第２对同源染体的一条染色体长臂，和第５对同源染色体的两条长臂均表现ＤＰ的Ｃ带特征，为异染色质末端带；另一方面，出现两者之间没有的现象，如：第８对同源染色体的长臂近末端显示异染色质带，为同型配对，而ｚｉ３３０的笫８对同源体不显带。这可能是染色体重组的结果。
There are few maize germplasms in China, and genetic diversity can only be obtained by distant hybridization. However, the wild separation of F2 in distant crosses makes the stability of an excellent trait often need to be selected after many generations, which takes time and effort. Using homozygous diploid from parthenogenesis, we selected elite pure line 540 (Fig.1) for only 2-3 years, compared to at least 5-6 years of conventional breeding. In this study, two diploid perennial maize (DP) hybrids were inbred with inbred lines of zi330, Xuan 9, MO17, Huangzao 4, etc. PEG, induced solitary reproduction. The agronomic traits (Fig.3) of pure line 540 were better than that of DP (Fig.2), but their resistance was better than that of their parents, zi330. Chromosomal banding results: The total number of bands in pure line 540 (Fig. 6) is 8, which is the same as the parent (Fig. 4 & 5). However, its C-band characteristics, on the one hand, combine the characteristics of both, ie, the long arm of one chromosome of the second pair of homologous chromosomes and the two long arms of the fifth pair of homologous chromosomes all exhibit the C-band characteristic of DP , The heterochromatic end of the band; the other hand, there is no phenomenon between the two, such as: 8 pairs of homologous chromosomes near the long arm shows heterochromatin, homologous pairs, and zi330 of the eighth pair Homologous body is not banding. This may be the result of chromosomal recombination.