Molecular Cytogenetic Characterization Of The Derivatives From Wheat-Thinopyrum Intermedium-Psathyrostachys Huashanica Hybrids With Resistance To Stripe Rust

The relatives of wheat possess a large number of useful genes, which can be used to improve the yield and quality of wheat. In order to broaden the genetic base and rich the genetic diversity of wheat, an efficient strategy is introgression some useful genes of relatives in the tertiary gene pool into wheat through distant crosses and chromosome engineering. Currently, people have made great achievements on distant hybridization of wheat. Many new types of material including alien addition lines, substitution lines and translocation lines were developed. Trigeneric hybrids can convene relatives of triticeae’s excellent genes. Creating trigeneric hybrids by hybridization between two amphiploids is an important way for inherited improvement. Moreover, different amphiploids have prolific genetic base, more separation types and variation types of trigeneric hybrids by the cross of amphiploids can be obtained. So a variety of materials with excellent characteristics of species can be created. The hybrid plants between T. aestivum cv. J-11 and Psa. huashanica were treated with colchicines in 2005, obtaining a new intergeneric amphiploid (PHW-SA,2n=8x=56, AABBDDNsNs). The amphidiploid has many good features, such as high resistance to stripe rust and stability on cytology. Wheat-Thinopyrum intermedium amphiploid Zhong 3, (2n=8x=56) was susceptible to stripe rust. In this study, Four F6 lines derived from the cross of PHW-SA×Zhong 3 were identified using agronomic traits investigation, cytogenetics, GISH and SDS-PAGE. The results are as follows:1. Cytogenetic analysis showed that all lines had 42 chromosomes with average of 0.83 univalents,20.57 bivalents and 0.01 trivalents. Lines K-13-649-3 and K-13-663-2 had 0.54 and 0.24 univalent, respectively, suggesting that these lines were stability on the cytogenetics. Lines K-13-656-3 and K-13-728-4 had 0.90 and 1.65 univalent, respectively, suggesting that these two lines were instability on the cytogenetics.2. Genomic in situ hybridization (GISH) revealed that these 4 lines were wheat-Th. intermedium translocation lines. The translocations were observed at the end of single chromosome, respectively.3. SDS-PAGE analysis showed that the K-13-649-3 and K-13-728-4 expressed specific glutenin bands consistent with their parent Zhong 3. K-13-656-3 and K-13-663-2 only expressed three bands, one specific glutenin band was disappeared in these two lines.4. In the field, all lines showed high resistance to stripe rust.