Liu Chenxu, Li Wei, Zhong Yu, Dong Xin, Hu Haixiao, Tian Xiaolong, Wang Lele, Chen Baojian, Chen Chen, Melchinger Albrecht E, Chen Shaojiang
College of Agriculture and Biotechnology, China Agricultural University, No.2 Yuan Ming Yuan West Road, Haidian District, 100193, Beijing, China.
Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Fruwirthstr. 21, 70593, Stuttgart, Germany.
Theor Appl Genet. 2015 Dec;128(12):2507-15. doi: 10.1007/s00122-015-2605-y. Epub 2015 Oct 6.
The QTL qhir8 affecting in vivo haploid induction in maize was mapped to a 789 kb region, embryo abortion rate and segregation ratios were analyzed, linkage markers for MAS were developed. The doubled-haploid (DH) technology has become an important tool for line development in modern maize breeding. However, the genetic basis of haploid induction remains elusive. In previous QTL mapping research, qhir8 besides qhir1 significantly affected haploid induction rate (HIR). Our objective was to fine map qhir8 and assess its effect on HIR, segregation distortion (SD) and embryo abortion (EmA). A total of 3989 F2 plants from the cross of inducers CAUHOI and UH400 were screened for recombinants in the qhir8 region. F2 plants and F3 plants from selfing progenies of 34 recombinant F2 plants were evaluated for HIR, SD and EmA. In parallel, we developed 31 new markers providing good coverage of the qhir8 region. We confirmed that qhir8 has an increasing effect on HIR and EmA, but not on SD. Moreover, we successfully narrowed down the qhir8 locus to a 789 kb region flanked by markers 4292232 and umc1867.
影响玉米体内单倍体诱导的QTL qhir8被定位到一个789 kb的区域，分析了胚胎流产率和分离比例，开发了用于标记辅助选择（MAS）的连锁标记。双单倍体（DH）技术已成为现代玉米育种中品系培育的重要工具。然而，单倍体诱导的遗传基础仍不清楚。在先前的QTL定位研究中，除了qhir1外，qhir8显著影响单倍体诱导率（HIR）。我们的目标是精细定位qhir8并评估其对HIR、分离畸变（SD）和胚胎流产（EmA）的影响。从诱导系CAUHOI和UH400的杂交后代中筛选出3989株F2植株，用于qhir8区域的重组体筛选。对34株重组F2植株自交后代的F2植株和F3植株进行了HIR、SD和EmA评估。同时，我们开发了31个新标记，对qhir8区域有良好的覆盖。我们证实qhir8对HIR和EmA有增加作用，但对SD没有影响。此外，我们成功地将qhir8位点缩小到标记4292232和umc1867两侧的一个789 kb区域。
