Phenotypic and genetic collections are new sources of biodiversity of cultivated wheat species: their establishment, reproduction, preservation and description in the gcd database

Institute of Cytology and Genetics, SB RAS, Novosibirsk

Head of the Institute:

Vladimir K.Shumny, Academician of the RAS,Professor
10 Lavrentyev Ave., Novosibirsk, 630090, Russia
Fax +(3832)331278
email: shumny@bionet.nsc.ru

Principal researchers:

E.B.Budashkina, Ph.D., Head of the cytogenetics laboratory
N.P.Goncharov, Ph.D., Head of the wheat genetics laboratory
S.F.Koval, Ph.D., Head of the laboratory of Genetic Basis of Plant Breeding
L.A.Pershina, Doctor of Sciences,
Head of the Sector of Wide Hybridisation and Tissue Culture
A.I.Shchapova, Doctor of Sciences, Principal Researcher

Project objectives

A database for collections of wheat genetic stocks (GCD) that have been developed and maintained at the Institute of Cytology and Genetics since 1970 will be established. During Project implementation, a strategy will be developed, and a search for ways and means for establishment and preservation of the “secondary” gene pool of cultivated plants will be conducted. For this purpose, collections of phenotypes and genotypes of wheats differing in ploidy levels (2n=14, 28, and 42) will be used.

Background and significance of objectives

Low genetic variability in most agricultural crops, including common wheat, makes their breeding very difficult to do. It is suggested to circumvent this problem by involving wild related species (forms with introgressed characters (Fig. 1), artificially developed wheat amphidiploids (re-synthetics)) and also by developing mutes (Fig. 2) and aberrants, i.e. by producing a “secondary” gene pool. However, the reduction of the natural distribution areas of wild endangered wheat species as well as of their polymorphism due to their reproduction in small populations in the gene banks results not only in gene pool erosion, but also decreases the potential biodiversity of the cultivated wheat species. To knowledgeably preserve the biodiversity of samples maintained as small-size populations, the sample should be fuller genetically characterised. This will allow goal-oriented preservation of the natural gene pool of the samples.

Clearly, it is important to improve methods aimed at preservation of the “secondary” gene pool, to develop strategies specifically designed for the “secondary” gene pool, which is frequently genetically unstable at the early stages of plant development and reproduction. Plant forms composing the “secondary” gene pool have not yet reached a formal botanical status and, therefore, they can disappear at any time, and a flexible mechanism is needed to maintain them. The participants of the proposed project possess unique collections of numerous phenotypic and genotypic characters of wheats at different ploidy levels as bases. The retention of forms resulting from re-synthesis of polyploid wheats also demands at the first step their classification and assignment to definite botanical categories. For this reason, the problem of re-synthesis and/or improvement of the existing biodiversity may be resolved/achieved not only by setting up a “secondary” gene pool, but also by defining ways and means for its preservation and use. The authors of the proposed project have set up phenotypic and genetic collections of wheats at different ploidy levels (2n=14, 28 and 42) as a result of breeding at the Institute of Cytology and Genetics (Novosibirsk) for many years. A comprehensive list of samples only in an isogenic lines collection has been published (Koval, 1997). The first step of the retention of forms re-synthesised from polyploid wheat is their classification and assignment to correct biological categories. Therefore, the existing biodiversity may be re-synthesised and/or improved provided that appropriate material is developed and the mechanisms for its registration, maintenance, preservation, and use are defined.

A major goal of the proposal is to derive lines with known genetic control from rare, wild, and cultivated wheat species. It is expected that in the process of the derivation of the lines, the gene pool of wheats will be ensured.

Research plan: approaches and methods

The team of the Institute has collected and established phenotypic and genotypic collections of morphological (Fig. 3), physiological and biochemical characters of di-, tetra- and hexaploid wheats (including isogenic lines, Fig. 4). A number of genes have been introgressed from other wheat species. Introgressed forms of common wheat (2n=42) containing identified genetic material of endemic tetraploid and diploid wheats have been developed for the first time. Thus, a large number of genes in the collections have been introgressed from related species. Introgressed forms of common wheat (2n=42) have been developed for the first time (fig. 5). These introgresed wheats contain identified genetic material from endemic tetraploid and diploid wheat species, they are isogenic for genes controlling spring vs winter growth habit. A genetic collection of diploid wheat and goat grasses (2n=14) has been set up. The collection is under study.

The authors of the project are competent in application of the methods needed to analyse, develop and maintain the plant material.

Expected results

Further development and maintenance of the established genetic collections at three different ploidy levels will make it possible to:

Furthermore, a strategy for the preservation and use of the gene pool of wild wheat relatives as a “secondary” gene pool will be suggested.

A methodical basis for the maintenance of phenotypic and genotypic collections, including isogenic wheat lines at different ploidy levels will be provided.

Ways and means for the production of new forms that may be used in programs for biodiversity will be elaborated.

A database of identified genes of wheats at different ploidy levels (2n=14, 28 è 42) will be set up.

List of publications of participants related to the project

image13.jpg (23568 bytes)

Fig. 1. Spikes:

  1. wild barley (Hordeum geniculatum) -

  2. wheat (T.aestivum) -

  3. F1 barleys-wheat hybrids obtained by backcrossing the hybrid with wheat.

image14.jpg (11156 bytes)

Fig. 2. Liguleless mute and normal Aegilops squarrosa L. The mute does not occur in nature.

image15.jpg (26023 bytes)

Fig. 3. A genetic collection of awnless (controlled by a single gene) and awned forms of di- (T.monococcum L.), tetra- (T.dicoccum (Shuebl.) Schrank.) and hexaploid (T.aestivum L.) wheat.

image16.jpg (20658 bytes)

Fig. 4. Cv. novosibirskaja 67 (left) and the derived lines isogenic for the hybrid chlorosis genes.

image17.jpg (11015 bytes)

Fig. 5. Resistant to fungi introgressed common wheat line containing T.timopheevii Zhuk. genetic material (right) and the fungus sensitive initial cv. (left).