Scholz Margret, Pendinen Galina
Institute for Breeding Research on Agricultural Crops, Julius Kühn-Institut, Federal Research Centre for Cultivated Plants, Sanitz, Germany.
Cytogenet Genome Res. 2016;150(2):139-149. doi: 10.1159/000455141. Epub 2017 Jan 21.
The pairing behaviour of the individual chromosome arms of Hordeum vulgare (Hv) with their homoeologous arms of H. bulbosum (Hb) at metaphase I of meiosis in tetraploid Hb × Hv hybrids and the frequencies of recombined Hv chromosome arms in selfed offspring were studied on differentially visualized chromosomes after fluorescent in situ hybridisation. The frequencies of paired Hv-Hb arms in the F2 and F3 hybrids were correlated with the frequencies of recombined Hv chromosomes in progenies. Self-generation of hybrids, the number of Hv and Hb chromosomes, and the number of recombined Hv chromosomes of the hybrids strongly influenced the Hv-Hb pairing frequency in meiosis. Within the offspring of F2 and F3 hybrids both Hv plants and hybrids were detected. In contrast, all progenies of the F4 hybrid were hybrids which exhibited centromere misdivisions. The highest frequencies of homoeologous pairing in hybrids and most recombinants were obtained for the barley chromosome 1HL. Recombinants for 4HL, 5HS, 6HS, and 7HS were rarely found. Meiotic pairing and recombinants involving chromosome 1HS were never observed. The results of this study demonstrate that fertile tetraploid interspecific hybrids with a high intergenomic pairing at meiosis are valuable basic material for introgression breeding in barley.
利用荧光原位杂交后差异可视化的染色体，研究了四倍体球茎大麦（Hb）×大麦（Hv）杂种减数分裂中期I时，Hv的各个染色体臂与其Hb的同源臂的配对行为，以及自交后代中重组Hv染色体臂的频率。F2和F3杂种中配对的Hv-Hb臂的频率与后代中重组Hv染色体的频率相关。杂种的自交、Hv和Hb染色体的数量以及杂种中重组Hv染色体的数量强烈影响减数分裂中Hv-Hb的配对频率。在F2和F3杂种的后代中，检测到了Hv植株和杂种。相比之下，F4杂种的所有后代都是表现出着丝粒错分的杂种。在杂种中，大麦染色体1HL的同源配对频率最高，重组体最多。很少发现4HL、5HS、6HS和7HS的重组体。从未观察到涉及染色体1HS的减数分裂配对和重组体。本研究结果表明，减数分裂时具有高基因组间配对的可育四倍体种间杂种是大麦渐渗育种的宝贵基础材料。
