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.

Travno-leguminozne smeše predstavljaju složene zajednice trava i leguminoza koje bolje koriste prirodne resurse i imaju niz pozitivnih osobina u odnosu na monokulturu. Cilj našeg istraživanja je bio da se ispita konkurentna sposobnost engleskog ljulja u smešama sa lucerkom i crvenom detelinom (50/50, 70/30) u uslovima đubrenja sa tri različita nivoa azota (0, 50, 100 kg ha-1). Prinos suve materije engleskog ljulja u smeši sa crvenom detelinom bio je veći u poređenju sa smešom sa lucerkom. Azot je imao značajan uticaj na prinos engleskog ljulja. Dodati azot je značajno povećao prinos engleskog ljulja, naročito doze od 100 kgN ha-1. Vrednosti relativnog prinosa iznad 1 (RI> 1), indeksa agresivnosti i indeksa konkurentske ravnoteže iznad 0 (Ag> Cbg> 0) ukazuju na veću konkurentsku sposobnost engleskog ljulja u odnosu na mahunarke. Кonkurentna sposobnost engleskog ljulja bila je veća kod 70/30 smeša i smeša sa lucerkom. N djubrenje povećava konkurentsku sposobnost ljulja i smanjuje konkurentsku sposobnost leguminoza.