Changes in botanical composition of alfalfa mixtures depending on the species and N fertilization

Abstract

Alfalfa is the most important forage plant in our country. It is mainly grown as pure crop for livestock nutrition, although it gives very good results when grown in mixture with other plant species. By growing in mixtures many advantages are achieved, the most important are: possibility for alfalfa to be used in grazing and reduced need for fertilization of grassland. In two year trial (2003-2004), changes in botanical composition of alfalfa mixtures depending on the present species in the mixture, i.e. their competitive abilities and fertilization with N, were monitored. Investigations showed that by ageing of crops the share of grasses increases and share of legumes and weeds decreases. Fertilization showed positive effect on strengthening of competitive abilities of grass in relation to leguminous species and increased share of weeds in forage mixtures.

Lucerka je najvažnija krmna biljka kod nas. Uglavnom se gaji kao čist usev za ishranu stoke, mada veoma dobre rezultate daje gajenjem u smeši sa drugim biljnim vrstama. Gajenjem u smešama ostvaruje se čitav niz prednosti od kojih su najvažnije: mogućnost korišćenja lucerke u ispaši i smanjenje potrebe đubrenja travnjaka. U dvogodišnjem ogledu (2003-2004) praćene su promene u botaničkom sastavu lucerkinih smeša u zavisnosti od prisutnih vrsta u smeši odnosno njihovih kompeticionih sposobnosti i đubrenja N. Ispitivanja su pokazala da sa starenjem useva dolazi do povećanja udela trava, a smanjenja udela leguminoza i korova. Đubrenje je pokazalo pozitivan efekat na jačanje kompeticionih sposobnosti travnih u odnosu na leguminozne vrste i povećan udeo korova u krmi smeša.