Published in Scientific Papers. Series A. Agonomy., Vol. LVI
Written by Hristo STOYANOV
Hybrids resulting from the wide hybridization in Poaceae, posses valuable qualities such as resistance to biotic and abiotic stress factors and are important for breeding programs of wheat culture. Six different second generation hybrid accessions resulting from wide hybridization between different types of wheat (Triticum aestivum, Triticum dicoccon) and Aegilops cylindrica were examined. Three of the accessions are obtained after self-pollination of the colchicined initial hybrids (a, e, f), and the other three (b, c, d)-through backcross of colchicined hybrids with bread wheat (Triticum aestivum) pollen. Only six of all hybrid seeds germinated and five survived to adult plants. Each accession exhibits a heterogeneous morphology and/or physiology, depending on the participating parental components. While in the first hybrid generation, a partial fertility in colchicined plants and complete sterility in non-colchicined plants was observed, in the examined second generation, all tested plants are fully sterile. The complete sterility was proven by the determined heterogeneous karyotype in an observation of metaphase chromosomes during the mitotic cell division. The number of chromosomes was often uneven and varies depending on the type of hybrids (selfed, backcross) and maternal component (Triticum aestivum, Triticum dicoccon). All plant hybrid accessions of the second generation that reached maturity were completely resistant to the pathogens of powdery mildew (Erysiphe graminis) and brown rust (Puccinia recondita). This makes the hybrids involving Aegilops cylindrica valuable plant resources of resistance which could be introduced into the genome of bread wheat.
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Aegilops cylindrica
