The impact of wheat and faba bean intercrop on the competitive interactions, grain yield, biochemical parameters and mineral content of leaves

Various studies highlight the advantages of intercropping, including the improvement of plant growth, stabilization of yield and reduction of economic and environmental risks common in monoculture systems. The research was carried out over two cropping seasons with different N fertilisation levels to compare winter wheat (Triticum aestivum L.) cultivar 'Wafia' and faba bean (Vicia faba L.) cultivar 'Alfia' cultivated as sole crops or intercropped. The aim of the current study was to evaluate intercrop efficiency using indices such as the land equivalent ratio (LER) and the interspecific (IE) and intraspecific (IA) interaction indices, and to verify whether the wheat and faba bean intercropping improves grain yield, biochemical properties and macronutrient uptake of two cultivars in the systems with low levels of nitrogen (N) inputs. The research results showed that without N input the LER > 1 indicates the most efficient use of environmental resources by intercropping. Without fertilisation, in the 2nd experiment, the IE of soft wheat was equal to 1 indicating that the presence of legume in the intercropping did not affect wheat plant productivity compared to sole crops in half density. However, in the 1st experiment, the presence of the legume was associated with a greater facilitation effect on wheat intercrop (IE > 1) inducing an increase in yield compared to half density. For both experiments, IA of wheat was less than 1 revealing that the wheat yield in half density was higher than that in sole crops in full density. Eventually, the intercrops for both experiments without any N fertiliser increased the protein, sugar, chlorophyll content and nitrate reductase activity of both intercropped species compared to the untreated and treated sole crops. Likewise, the uptake of macronutrients P and K was increased in faba bean intercropped in the 1st and 2nd experiment, respectively, when these elements were less available in the soil. However, Ca content did not show any significant effect. This allows us to conclude that intercropping of soft wheat and faba bean is a relevant way to reduce chemical inputs.