Evaluation of competitive ability of perennial ryegrass in mixtures with red clover and lucerne subjected to different levels of N

Abstract

Grass-legume mixtures represent complex communities of grasses and legumes that make better use of resources and have a number of positive traits in comparison to monoculture. The aim of our research was to examine competitive ability of perennial ryegrass in mixtures with lucerne and red clover (50/50, 70/30) in condition of fertilization with three different nitrogen levels (0, 50, 100 kg ha-1). Dry matter yield of perennial ryegrass in mixtures with red clover was higher compared to mixtures with lucerne. Nitrogen had a very significant impact on perennial ryegrass production. Added N significantly increase DM production of grass treatment with 100 kgN ha-1. The values, of relative yield above 1 (RY >1), aggressivity index and competitive balance index, above 0 (Ag > Cbg > 0) indicated higher competitive ability of perennial ryegrass in relation to legumes. Competitive ability of ryegrass was higher in 70/30 mixtures and mixtures with lucerne. N fertilization increases competitive ability of ryegrass and decreases competitive ability of legumes.

Keywords

• aggressivity
• competition
• grass-legume mixtures
• species balance
• yield