BIOLOGICAL RESOURCES OF FESTUCA ARUNDINACEA SCHREB. FROM THE SOUTH OF THE CENTRAL RUSSIAN UPLAND AS A SOURCE MATERIAL FOR BREEDING

The modern cultivar of reed fescue (Festuca arundinacea Schreb.) don’t have sufficient stability in a number of regions of Russia. So the study and mobilization of the genetic resources of this crop is an important area of breeding work. The south of the Central Russian Upland, due to its landscape conditions, has a high diversity of forms of economically valuable plant species. Landscape complexes with chalk outcrops are of particular interest. In habitats with chalk outcrops and river floodplains, populations of F. arundinacea with breeding value were selected. In two bookmarks of collection experiments (2014-2017 and 2020-2023), their comparative testing was carried out using the standard method. Soil: leached sandy loam chernozem (first bookmark of the experiment), typical light clayey chernozem (second bookmark of the experiment). The observations were carried out in accordance with the methodology of research on distinctiveness, homogeneity, stability of the F. arundinacea species UPOV TG/39/6. It was found that the habitat factor has a strong effect on most morphobiological features that are stably preserved under cultural conditions. It was revealed that the populations of chalk outcrops significantly differed from the populations of floodplains: by leaf width (50.4 % narrower), by grass height (33.6 % less). Negative Spearman correlations were revealed between dry matter yield and the number of shoots (rs = -0.849), the number of productive stems (rs = -0.894), the intensity of anthocyanin coloration of nodes (rs = -0.692), the number of productive stems (rs=-0.660). Positive relationships were established between the dry matter yield and leaf length (rs = 0.574), leaf width (rs = 0.822), flag leaf length (rs = 0.601), flag leaf width (rs = 0.523), and stem height (rs = 0.701). It was concluded that under chalk outcrops, F. arundinacea populations with low grass cover, narrow leaves, high shoot formation, and low dry matter yield are formed, which are sources for lawn varieties. Under floodplain conditions, tall broadleaf populations with high dry matter yield are formed, which are materials for forage varieties.