Productivity and stability of grasses in the Middle Balkan Mountains region

Natalia Georgieva, Valentin Kosev, Dimitar Mitev

Abstract: Perennial grasses have got greater attention in the past decade due to their potential to be productive over several years and their positive impacts on the environment. A great resource in this regard are the native species, which are well adapted to the specific conditions of the environment, but are often underestimated and irrationally used. The objects of study in the present research were 8 grasses (Festuca rubra, Lolium perenne, Dactilis glomerata, Arrhenatherum elatius, Festuca arundinacea, Briza maxima, Trisetum flavescens, Agrostis alba), typical for the Middle Balkan Mountains region, in order to assess their productivity and stability. The two-factor analysis of variance in terms of dry mass yield revealed significant influence of the factors of species, environment, and their interaction. During the 9-year experimental period, the highest yield was demonstrated by F. rubra (5.75 t ha-1), followed by F. arundinacea (5.54 t ha-1) and A. elatius (5.43 t ha-1). The stability parameters, calculated by the methods of regression analysis defined as stable the species of A. elatius and A. alba, and those, calculated by variance and non-parametric analyzes – F. rubra, D. glomerata and F. arundinacea. Differences in the stability assessment of the individual parameters are due to the fact that the different methods are based on different concepts of stability. The GGE biplot analysis, which integratedly assesses the species for their productivity and stability, identified F. arundinacea and A. elatius as the most favorable combining of these indicators. Trisetum flavescens was also characterized by good stability and average productivity. These species are suitable for cultivation in a wide range of environmental conditions.

Keywords: adaptability; grain mass yield; grasses; stability

Date published: 2023-10-20