B. HADZHIIVANOVA, V. BOZHANOVA and D. DECHEV
Field Crops Institute, BG - 6200 Chirpan, Bulgaria
HADZHIIVANOVA, B., V. BOZHANOVA and D. DECHEV, 2012. Interspecific hybridization between durum wheat and Aegilops umbellulata (Zhuk.). Bulg. J. Agric. Sci., 18: 713-721
The possibility for obtaining of interspecific hybrids between three durum wheat genotypes (Triticum durum, 2n = 4x = 28, AABB genomes) and one accession of Aegilops umbellulata (2n = 2x = 18, UU genome) during two different seasons has been studied. A low crossability rate of 3% average for all genotypes over two years was achieved. The observed variation of crossability is due to a greatest extent to the genotype of durum wheat parent with 82.91% from total variation. Hybrid plants were obtained only by means of embryo rescue method. The ability for in vitro regeneration was still independent of crossability of used durum wheat genotypes. All received F1 hybrids plants were identical they exhibited good tillering ability and manifested traits from both parents. In spite of the observed partially fertility in F1 hybrids between durum wheat and Aegilops umbellulata no germination of the hybrid seeds was ascertained. BC1 seeds were obtained from F1 hybrids of hybrid combination Beloslava × Aegilops umbellulata after backcrossing to the durum wheat parent. An increase of crossability with advancing of backcross progenies – from 1.6% in BC1 hybrids to 26.2% in BC2 hybrids has been found. Meiotic abnormalities including dyads and triads at the end of microsporogenesis as well as uninucleate microspores with a different shape and size were observed suggesting production of unreduced gametes in this cross.