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用玉米给六倍体小麦授粉时,20-30％的小花中产生了胚、胚乳或者胚和胚乳。合子细胞分裂中期具有预期的F_1染色体组合,即21条小麦和10条玉米染色体,这便证明胚来源于种间杂交。然而,杂种在染色体组型上很不稳定,并且所有的玉米染色体在为数不多的细胞分裂的第一周期丢失而成为单倍体小麦胚。发生受精作用的多数小花仅有一个保留着未受精极核的胚,胚乳发育往往很不正常。也许因为缺少足够的胚乳,对小麦×玉米的杂种胚采取常规的胚营救法很难发育成植株。如果把含有异花授粉小花的小穗在授粉2天后离体培养三周,有生活力的胚发育成单倍体小麦植株的频率较高(超过100倍)。玉米能影响在Kr可交配性位点载有显性等位基因小麦的受精,通常会降低小麦和异源物种间的杂交受精率,并且获得中国春(Hope 5A) (kr1,Kr2)和HopPe(Kr1,Kr2)以及中国春(kr1,kr2)的加倍了的单倍体种子。小麦×玉米杂交可用于产生小麦单倍体,并且也能使玉米的DNA转移到小麦中。
When pollinating hexaploid wheat with corn, embryos, endosperm or embryos and endosperm are produced in 20-30% of the florets. Zygotic cell metaphase has the expected F1 chromosome combination, that is, 21 wheat and 10 maize chromosomes, which proves that the embryos are derived from interspecific hybridization. However, the hybrids are very labile on the karyotype and all of the maize chromosomes are haploid wheat germ in the first cycle of a few cell divisions. Most fertilizers only produce embryos that retain unfertilized nuclei, and endosperm development is often abnormal. Perhaps because of the lack of sufficient endosperm, it is very difficult to develop plants using conventional embryo rescue methods on wheat × maize hybrid embryos. If spikelets containing cross-pollination florets were cultured ex-vivo for two weeks after pollination for two days, viable embryos developed higher frequency (more than 100-fold) of haploid wheat plants. Maize can affect the fertilization of wheat bearing the dominant allele at the Kr mashing site and generally reduce the fertilization rate of wheat and heterologous species and obtain Hope 5A (kr1, Kr2) and HopPe (Kr1, Kr2) and Chinese Spring (kr1, kr2) doubled haploid seeds. Wheat × maize hybrids can be used to produce wheat haploid, and can also transfer maize DNA into wheat.