PRODUCTION AND CYTOGENETICS OF INTERGENERIC HYBRIDS OF TRITICUMAESTIVUM WITH Aegilops variabilis and Ae.vavilovi.

Abstract

Intergeneric hybrids between Triticum aestivum L, and Karnah bunt (Neovassia indica) resistant accessions of two Aegilops species were produced in different frequencies. Aegilops variabilis was hybridized with Genaro 81, Mri- Buc-Pvn *S* and Chinese Spring at frequencies of 5.0 to 29.0%. The endosperm formation was normal, mature seeds were slightly shrivelled but germinated normally. The T. aestivum x Ace variabilis hybrids, genomica\ky represented as ABDUS, were cytologically normal, with 2n=5X=35 chromosomes. The mean meiotic associations at metaphase-I were categorized as pairing and expressed as 33.96 univalents + 0.52 rod bivalents over 56 meiocytes analyzed with a 0.52 mean Chaismata frequency. Hybrid production frequencies of T. aestivum cultivars Sind 81, ZA-77, Buc"S", Chinese Spring with Aa vavilcvi ranged between 1.7 to 313% Meiotic associations were 33.31 univalents + 0.19 ring bivalents + 2.94 rod bivalents + 0.81 trivalents over 32 meiocytes characteristic of 2n=6x=42 chromosomes that genomically were ABDDMS with a 4.94 mean chiasmata frequencyo The germplasm offers avenues of alien addition line development or Ph locus manipulation; events currently lacking for applied objective exploitation of these two species.