ARS | Publication request: THE IDENTIFICATION OF DUPLICATE ACCESSIONS WITHIN A GRASS GERMPLASM COLLECTION USING RAPD ANALYSIS.

Submitted to: Agronomy Abstracts
Publication Type: Other
Publication Acceptance Date: November 13, 2002
Publication Date: November 13, 2002
Citation: Bradley, V.L., Kisha, T.J., Johnson, R.C. 2002. The identification of duplicate accessions within a grass germplasm collection using rapd analysis [abstract]. Crop Science Society of America. p. 131923.

Interpretive Summary: There are almost 18,000 accessions in the Western Regional Plant Introduction Station (WRPIS) temperate grass collection. Germplasm managers at the station have suspected for many years that some grass accessions are duplicates of others. Although the original source of these suspected duplicates may have been the same, it is possible that subsequent cultural practices have altered the genetic make-up of the seed maintained at the WRPIS, thus making these accessions unique from one another. A field comparison of morphological traits in suspected duplicate accessions is possible but usually not practical on a large scale. A minimum of two years of growth is required before data may be gathered on perennial grasses, and much of the data is influenced by environment. Therefore, the WRPIS grass germplasm managers are developing procedures to identify duplicate accessions more quickly using molecular markers. Three populations (A, B, and C) of Elymus trachycaulus 'Primar', a self-pollinated grass, were planted and twenty-four plants of each population were sampled. Using Random Amplified Polymorphic DNA (RAPD) analysis, it was found that these populations were significantly different from one another. However, population B appeared to have the most genetic richness.

Technical Abstract: Germplasm managers at the Western Regional Plant Introduction Station (WRPIS) have suspected for many years that some grass accessions are duplicates of others. A field comparison of morphological traits in suspected duplicate accessions is possible but usually not practical on a large scale. Therefore, the WRPIS grass germplasm managers are developing procedures to identify duplicate accessions more quickly using RAPD analysis. Twenty-four plants of each of three populations (A,B, and C) of Elymus trachycaulus 'Primar', a self-pollinated grass, were grown in the greenhouse. When plants reached the three to four leaf stage the top two centimeters of new leaves were removed and DNA was extracted. The DNA was amplified and fragments were separated on agarose gels and stained with ethidium bromide. Eight of the 11 RAPD primers used produced legible polymorphic markers, and 54 were scored. Although all three populations differed in allelic frequency, population B appeared to have the highest allelic richness.