Weed control by cover crop residues of sunflower (Helianthus annuus) and buckwheat (Fagopyrum esculentum) in organic winter faba bean

Abstract

A two-factorial field trial with winter faba bean was carried out at the experimental farm for Organic Agriculture ‘Wiesengut’ close to Bonn, Germany, in 2007 and 2008 respectively. The objective of the experiments was to quantify and evaluate the influence of the factors variety (Hiverna and Diva) and cover crop species (sunflower, buckwheat, green fallow) on a range of growth, yield and weed parameters of organically grown winter faba bean. Data were subjected to ANOVA with subsequent Tukey-Test. Crop height of winter faba bean was significantly lower after cover crop sunflower compared with buckwheat. In a joint two-year analysis grain yield of winter faba bean after cover crop sunflower was significantly lower (3.09 t DM ha^–1) compared with buckwheat (3.48 t DM ha^–1). Weed ground cover and biomass were significantly lower after cover crop sunflower and buckwheat compared with green fallow at several assessment dates of both trials. Results have shown that under the climatic conditions of the Rhineland area the production of organic winter faba bean can be realized with economic yields. The practical use of cover crops such as sunflower known to feature allelopathic effects against weeds still deserves further research.

DOI: 10.5073/JfK.2012.07.01, https://doi.org/10.5073/JfK.2012.07.01