Kynast R G, Davis D W, Phillips R L, Rines H W
Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK.
Sex Plant Reprod. 2012 Jun;25(2):111-22. doi: 10.1007/s00497-012-0182-7. Epub 2012 Feb 25.
Hybrid (oat×maize) zygotes developed into euhaploid plants with complete oat chromosome complements without maize chromosomes and into aneuhaploid plants with complete oat chromosome complements and different numbers of retained individual maize chromosomes. The elimination of maize chromosomes in the hybrid embryo is caused by uniparental genome loss during early steps of embryogenesis. Some of these haploid plants set seed in up to 50% of their self-pollinated spikelets. The high fertility was found to be mainly caused by formation of numerically unreduced female and male gametes (nunreduced=3x+0…3=21…24 chromosomes). Gamete formation involves meiotic nuclear restitution. The restitution process is caused by an alternative type of meiosis. It follows the model of levigatum-type semi-heterotypic divisions, but with a formation of the nuclear membrane at the transition from telophase I to interkinesis, which resembles the model of pygaera-type pseudo-homotypic divisions. We propose the name haploid meiotic restitution for this particular process combination. We discuss the use and implications of the specific process of gamete formation in F1 (oat×maize) plants.
杂种（燕麦×玉米）合子发育成具有完整燕麦染色体组且不含玉米染色体的整单倍体植物，以及具有完整燕麦染色体组和不同数量单个保留玉米染色体的非整单倍体植物。杂种胚中玉米染色体的消除是由胚胎发生早期单亲本基因组丢失引起的。这些单倍体植物中，高达50%的自花授粉小穗结籽。发现高育性主要是由数量未减数的雌配子和雄配子（未减数=3x+0…3=21…24条染色体）的形成所致。配子形成涉及减数分裂核 restitution。该 restitution 过程由一种另类减数分裂引起。它遵循 levigatum 型半异型分裂模式，但在从末期 I 到胞质分裂间期的转变过程中形成核膜，这类似于 pygaera 型假同型分裂模式。我们为这种特定的过程组合提出“单倍体减数分裂 restitution”这一名称。我们讨论了 F1（燕麦×玉米）植物中配子形成特定过程的用途及影响。
