Abstract:

Chromosome 3C of Aegilops triuncialis are of the ability to be transferred preferentially in the case of its monosomic status in wheat background. Whereas, those gametes without 3C would result in chromosome structural changes including deletion and translocation. Haynaldia villosa is reported to be resistant to several wheat diseases, such as powdery mildew, rust, take-all, eyespot and wheat spindle streak mosaic viruses. Chromosome disomic addition lines involving all seven H. villosa chromosomes, disomic substitution lines involving chromosomes 4V have been developed and characterized. Eyespot and take-all resistance gene is mapped on chromosome 4VL. The objectives of this study were to develop more translocation lines involving chromosome 4V, and supply new germplasm for wheat breeding. Triticum aestivum-Haynaldia villosa 4V disomic addition line was crossed to T. aestivum “Norin 26”-Ae. triuncialis 3C disomic addition line , and the hybrids F1 were then self pollinated. Both chromosome C-banding and fluorescent in situ hybridization (FISH) were applied to screen chromosome variations of 4V. In this case, total genomic DNA of H. villosa was labelled by fluoresceint-12-dUTP as probes and total genomic DNA of Chinese Spring as the block. One heterozygous translocation line involved in 4V and 4A (J176-33) was identified from F₂, and a homozygous translocation line (CQZ55) was selected from the offspring of J176-33 and confirmed by chromosome pairing analysis at meiosisⅠof pollen mother cells (PMC). The results of simple sequence repeat（SSR）and restriction fragment length polymorphism (RFLP) analyses indicated that CQZ55 is consisted of 4VS, a part of 4VL near the centromere and distal part of 4AL, and designated as T4VS·4VL-4AL. This translocation line showed high resistance to wheat spindle streak mosaic virus.

Key words: Triticum aestivum, Haynaldia villosa, T4VS·4VL-4AL Translocation, C-banding, Fluorescent in situ hybridization, Molecular marker