Maize Performances as Influenced by Winter Cover Crop Green Manuring

BACKGROUND. Accumulation of organic matter and nitrogen in the soil, weed suppression and yield in-crease of the following main crop are the most rele-vant benefits that can be achieved by incorporating selected cover crops in the soil as green manure. This study aims at evaluating the effect of green manur-ing by different cover crops on yield and weed sup-pression of a grain maize crop which was fertilised with mineral nitrogen at different rates. METHODS. This study was conducted over two years (1992/93 and 1993/94) in Central Italy. Each year maize (Zea mays L.) was planted after green ma-nuring of four different cover crops [Ryegrass (Loli-um multiflorum Lam.), subclover (Trifolium subter