Produire durablement des blés riches en protéines par la culture en association de blé d’hiver et de pois protéagineux d’hiver.

Crops in association cereals - legumes are integrated into the ecologically intensive agriculture approaches. Since December 2012, The Crop Production Unit of Gembloux Agro-Bio Tech (ULg, Belgium) study how to optimize the intercropping conduct of winter peas and winter wheat in temperate climate. The objective of the study is to optimize the cultivation conditions of the wheat-peas association for a reliable production of dry matter at least equivalent to that produced by both pure crops on the same surface by improving the protein yield while reducing nitrogen fertilizer required for this production.
Through the symbiotic Rhizobium activity, legumes have the advantage to be free of nitrogen fertilizers. The combination of legumes and cereals allows in a low input system a direct exploitation by the cereal of nitrogen released by the legume during the culture. This exchange especially present late in the culture provides cereal nutrition on a phenological development stages particularly important to grain quality. With this “natural” contribution of nitrogen, a superior quality of wheat is obtained, more important of a pure cropping. The association allow to obtain a protein levels greater than 16% with the Edgar wheat variety with only 80 kg N / ha of fertilizer against 11.4% in pure culture under the same growing conditions. This bonus is also obtained for Zeleny index, gluten index and hardness.