In our days the problem of maintenance and identification of plant genetic recourses which some authors mention about (MacKenzie, 1998; Steiner et al., 1997), become the main problem for several gene banks. Most of them were founded in the middle of 60-70-s and now some of them have a problem of multiplication of accessions after maintaining this material during 20-30 years (Diederichsen et al., 1999). Despite of it some of them have no precise criteria of seed samples identification at the species level, don't mention about conservation of intra-specific diversity.

In that time Vavilov Institute of Plant Industry (Russia) during several decades has been used precise system of multiplication and identification of any plant materials which are maintained in the base and working collections. This system is based on detailed and carefully developed specific and intra-specific taxonomic systems of each genus as a whole. The foundation of this classification was formed by distinctly visible and clearly discernible morphological characteristics. Most of these taxonomic systems were developed under supervising by N.I.Vavilov in 20-30-s, further after evaluation new specific and intra-specific plants diversity the classifications were added and changed. The main principle of these taxonomic systems is that natural intra-specific classification should, in our opinion, be based on a complex approach to the concept of the rank of botanical variety as an objective unit in complicated polymorph specific systems.

The taxonomic system (Mordvinkina, 1936) supplemented by genetic, karyological and morphological data with the addition of newly described species served as a foundation for the development of a new classification of Avena L. (Rodionova et al., 1994). Keys for the identification of all species within this genus together with accepted additions (Loskutov, 1998a) are used for maintenance collection of oats. After many years of studying morphological diversity of wild oat collection (Loskutov, 1998b) with detailed analysis of existing taxonomic systems, an intra-specific system of species was developed. This system represents the whole spectrum of intra-specific polymorphism. Value of detailed systems of species explicitly developed up to the botanical variety and form levels lies in the fact that these systems involve a variety of traits and, first of all, morphological ones, which have been used for a long time to identify and, consequently, to preserve and study the whole diversity of oat species.

Specific and, especially, intra-specific classification presently becomes more and more important not only in botanical, breeding and plant science research and genebank activities related to preservation of integrity in viable seed materials. If such material has been incorrectly identified with inaccuracies in attributing it to a certain species, the results of such research could be erroneously transferred onto other closely related species and genera.

Thus, development and, primarily, practical application of complex taxonomic systems of natural polymorphism within a species and within the entire genus provide for better understanding, more detailed study and safer conservation of the whole global diversity of plant genetic resources.

References

1. Diederichsen A., Kessler D., Williams D. Germplasm of the genus Avena at Plant Gene Resources of Canada (PGRC). Oat Newsletter, 1999, v.45.
2. Loskutov, I.G. 1998a. Database and taxonomy of VIR's world collection of the genus Avena L. Report of a Working Group on Avena. Fifth meeting, Vilnius, Lithuania. IPGRI, Rome, Italy, 26-31.
3. Loskutov, I.G. 1998b. The collection of wild species of CIS as a source of diversity in agricultural traits. Genetic Resources and Crop Evolution, v.45, 4, 291-295.
4. MacKenzie D. Growing problems in seed banks. New Scientist., 1998, 157: 2121.
5. Mordvinkina, A.I. 1936. Oves – Avena. In: Kulturnaya flora SSSR. Khlebnye zlaki. Rozh, Yachmen, Oves. (Cultivated flora of the USSR. Grain cereals. Rye, Barley, Oats). v.2., M.-L., 333-438 p. (russ.).
6. Rodionova, N.A., Soldatov V.N., Merezhko V.E., Yarosh N.P. & V.D. Kobylyansky, 1994. Kulturnaya flora SSSR. Oves. (Cultivated flora of the USSR. Oat). v.2, part.3, 1994, Kolos, M., 367 p. (russ.).
7. Steiner A.M., Ruckenbauer P., Goecke E. Maintenance in genebanks, a case study: contaminations observed in the Nurnberg oats of 1831. Genetic Resources and Crop Evolution. 1997, 44: 6, 533-538.

The problems of maintenance of plant genetic recourses and intraspecific taxonomy of plants