Sowing ratio, NS fertilisation and interactions of Lolium sp. and Festulolium grown in mixtures with Trifolium repens

Abstract

Current ecological trends for production of forage for livestock indicate a need for small usage of fertilisers while increasing productivity. The study aimed to assess yield and interactions of selected Lolium and Festulolium species grown in mixtures with Trifolium repens and fertilised with NS, regarding mutual interactions based on available indicators. A two-year field study (2016–2017) was carried out in southern Poland and the research objects were designed on degraded chernozems. The highest yield was observed for mixtures: L. multiflorum + T. repens and L. × boucheanum + T. repens sown in the proportion 50 : 50, fertilised with N₅₀S₁₅. The mean dry matter yield was higher in the 1^st year of the study, in all variants of fertilisation and types of mixtures. The land equivalent ratio differed for species in individual objects, for individual cuts and study years, and was most often higher than 1.0, which points to a positive interference between species in mixtures. Also, the competitive ratio index was often higher than 1.0, which means that grass species were more competitive than white clover. However, in the second year of study T. repens was dominant in multiple objects.