Yield performance and weed control efficiency of organically managed silage maize double cropping systems

Maize is among the three most important crops worldwide, while its multifunctional nature allows a diversified use. However, the traditional (silage) maize production often has negative side-effects related to the unprotected soil surface — e.g., erosion, weed pressure and related mechanical weed control. There are several alternative management systems to enhance the sustainability of (silage) maize production. However, the means and strength of influence are still unclear in some cases. Therefore, the current thesis evaluated 18 alternative silage maize production systems — double cropping systems (DCS) and double cropped, mulch systems (DCMS) — to a traditionally managed control (SCS) under organic conditions. Factors comprised of location (n = 3), year (n = 3), system (n = 2), first crop (group) (FC (group) — winter pea, hairy vetch (pure legumes), and their mixtures with rye, control), management — incorporating FC use and tillage (DCS no-till (NT), DCS reduced till (RT), DCMS terminated with roller-crimper (Roll), SCS control), fertilization and mechanical weed control — and row width (75 cm, 50 cm). Measured parameters were yield quantity (FC, silage maize and total harvested biomass — FC and maize), yield quality (dry matter content, stability), and weed pressure (weed cover, dominant weed species community composition). Posterior orthogonal subsets (foci) of modelled results for hypotheses testing, as well as the visual presentation of these differences with confidence intervals allowed a detailed, yet comprehensive report of the findings.