A report of the work in National Bioresource Project-Wheat in Tottori University: Wheat lines with alien chromosome

Hisashi Tsujimoto, Masahiro Kishii¹, Quanwen Dou² and Hiroyuki Tanaka

Laboratory of Plant Genetics and Breeding Science, Faculty of Agriculture, Tottori University, Tottori 680-8553 Japan

Present addresses: ¹CIMMYT, ²Northwest Plateau Institute of Biology, Chinese Academy of Science, China

Corresponding author: Hisashi Tsujimoto

E-mail: tsujim@muses.tottori-u.ac.jp

In long history of genetical studies of wheat, researchers have produced many interspecific or intergeneric hybrids and amphidiploids (Maan and Gordon 1988). These plants were further used as the source of wheat lines with a pair of alien chromosomes called ‘alien chromosome addition lines’ (Shepherd and Islam 1988). These plants are valuable to introduce useful genes to wheat from the other species (Friebe et al. 1996). Many of the lines have been incorporated in practical breeding programs. These lines are also interesting for basic genetical studies. For example, cytological analysis with genomic in situ hybridization (GISH) reveals the behavior of the chromosomes in interphase nuclei (Fig. 1).

In 2003 we joined the National Bioresource Project-Wheat. We re-evaluated the chromosomes, propagated fresh seeds and stored them in cold and dry room (Fig. 2, Table 1). Some of the seeds were distributed to researchers. The lines were classified into several groups to make users access easily to the appropriate lines in the database (Table 2). We could successfully propagate many of the lines. However, we failed to do in some strains because of severe sterility, no germination, or instability or absence of expected alien chromosomes. This year the stocks were transferred from Tottori University to Kyoto University for centralized control following advice by the government. The service of material distribution will be continued from Kyoto University.

Most of the present common wheat is the derivatives of a single or a limited numbers of interspecific hybrids between tetraploid wheat and Aegilops tauschii that appeared mere 8,000 years ago. All variations in common wheat are thus those accumulated in such short period of the evolution. To expand variation of common wheat for future demand, genes of the other species are indispensable. However, other species, especially wild species, are not able to be evaluated as ‘wheat’ because of great morphological difference from wheat. Once promising gene is discovered in such species by molecular survey, the wheat line carrying the chromosome with the gene would have great value to demonstrate the phenotype. Connection of the genetical studies to breeding programs will have an impact on world agriculture.

References

Friebe B, Jiang J, Raupp WJ, McIntosh RA, Gill BS (1996) Characterization of wheat-alien translocations conferring resistance to diseases and pests: current status. Euphytica 91: 59-87.

Maan SS, Gordon J (1988) Compendium of alloplasmic lines and amphiploids in the Triticeae. Proc 7th Int Wheat Genet. Symp 1325-1371.

Shepherd KW, Islam AKMR (1988) Fourth compendium of wheat-alien chromosome lines. Proc 7th Int Wheat Genet Symp 1373-1398.