Effect of intercropping on crop yield and chemical and microbiological properties in rhizosphere of wheat (Triticum aestivum L.), maize (Zea mays L.), and faba bean (Vicia faba L.)

In this study, we investigated crop yield and various chemical and microbiological properties in rhizosphere of wheat, maize, and faba bean grown in the field solely and intercropped (wheat/faba bean, wheat/maize, and maize/faba bean) in the second and third year after establishment of the cropping systems. In both years, intercropping increased crop yield, changed N and P availability, and affected the microbiological properties in rhizosphere of the three species compared to sole cropping. Generally, intercropping increased microbial biomass C, N, and P availability, whereas it reduced microbial biomass N in rhizosphere of wheat. The rhizosphere bacterial community composition was studied by denaturing gradient gel electrophoresis of 16S rRNA. In the third year of different cropping systems, intercropping significantly changed bacterial community composition in rhizosphere compared with sole cropping, and the effects were most pronounced in the wheat/faba bean intercropping system. The effects were less pronounced in the second year. The results show that intercropping has significant effects on microbiological and chemical properties in the rhizosphere, which may contribute to the yield enhancement by intercropping.