|Almouslem, A. - FULBRIGHT SCHOLAR, SYRIA|
|Peterson, Terrance - PLNT SCI, NDSU, FARGO, ND|
Submitted to: International Crop Science Congress Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: July 22, 1996
Publication Date: N/A
Technical Abstract: Durum wheat (Triticum turgidum L.) is an allotetraploid (2n = 4x = 28) with AA and BB genomes. Although the homoeologous relationships between chromosomes of the A and B genomes have been known for almost four decades, the degree of pairing relationship between the two chromosome sets is not known. Euhaploids (2n = 2x = 14; AB) with and without the homoeologous pairing suppressor Ph1 provide excellent tools for studying intergenomic chromosome pairing relationships. Euhaploids with Ph1 were generated from eight durum cultivars, and euhaploids without Ph1 were produced from the disomic mutant ph1c ph1c of Cappelli, and a durum substitution line LDN5D(5B), where chromosome 5B was substituted by 5D. All these cultivars were crossed with maize and 16 days after pollination the embryos were recovered on MS medium. A total of 134 haploid seedlings were obtained from 14272 florets pollinated. Recovery percentages of haploid seedlings from pollinated florets were 1.3% (Durox), 0.2% (Langdon), 1.2% (Lloyd), 4.3% (Medora), 0.8% (Monroe), 2.9% (Renville), 0.8% (Vic), 0.1% (Cappelli), and 1.1% [LDN5D(5B)]. Whereas there was very little pairing in the presence of Ph1, substantial intergenomic pairing occurred in the absence of Ph1. Data on chromosome pairing will be presented and the intergenomic relationship discussed.