Forage legumes and grasses. Which is better: pure stands or mixture?

摘要

Intercropping of grasses and legumes could represent a viable alternative to rotation due to the ready availability of nitrogen as well as their complementary development. The present data have allowed an accurate assessment of convenience for the cultivation in pure stands or mixture some legumes (berseem and squarrose clover, hairy vetch and burr medic) and grasses (ryegrass and oat), commonly used in the Mediterranean environments. In a 5-year trial, the average annual dry matter yield was 4.56 Mgha~(-1). Annual and seasonal yield were very variable, due to weather variability that determined a different timing of growing. The drought in the last year caused a reduction in the average production. Protein content analyses have allowed a further assessment of the protein production of pure stands and mixtures. Land Equivalent Ratio (LER) was calculated, for every season and year, both for forage and protein production.