Production of Various Ploidy Hybrids from Wide Crosses Between Hordeum vulgare (2x) and H. Bulbosum (2x, 4x).

Domestic barley (Hordeum vulgare L.) is one of the oldest field crops and is one of the most widely cultivated cereal crops in the world. Salinity and drought are the most important problems facing crop productivity around the world. Also, intensive cultivation of barley has led to a narrowing of its genetic base, but traits lost in domestic barley can still be found in wild species. Consequently, the wild species are an important genetic resource for breeding programs. Two species were used in this study; domestic barley (H. vulgare subsp. spontaneum), an annual with some salinity tolerance (five accessions), and bulbous barley (H. bulbosum), a perennial with strong tolerance to salinity (six accessions). Accessions were obtained from GRIN. H. bulbosum germplasm was screened for saline tolerance at germination and seedling growth. Crosses were made with H. vulgare to transfer that tolerance. This interspecific hybridization required embryo rescue and diploidization with colchicine. Parents/progeny were screened for ploidy level using flow cytometry. Comparison between the hybrid progeny and their parents, were compared with their salinity tolerance. Crosses between H. vulgare (2x) x H. bulbosum (2x) were produced haploid progeny, while crosses between H. vulgare (2x) x H. bulbosum (4x) were produced triploid hybrids as well as aneuploids. Parental crosses gave varying percentages of: seed set, viable, abnormal, and inviable seed. Seed set ranged from 33.3 to 89.8%. Progeny germination ranged from 0 to 28.6%. These hybrids may have tolerance to other biotic or abiotic stress conditions. They need to screen their tolerance to other stresses.