Maize–common bean intercropping has a long tradition in Mesoamerican agriculture, where the two crops were domesticated. The practice was introduced and maintained in certain regions of Europe, such as Transylvania where it remains valued in small-scale farms for its agronomic and nutritional complementarity.
To investigate the mechanisms underlying species interactions in this system, we established an intercropping experiment involving 200 European climbing bean lines grown with three maize landraces in France and Romania over two years. The three maize landraces were considered as distinct biotic environments (E) for bean growth. We analyzed bean phenotypic responses in both above-ground and root traits across these biotic environments. Direct and indirect genetic effects were assessed by mapping bean and maize phenotypic traits, respectively, onto the bean genome (G), and G×E interactions were tested using contrasts among maize landraces. This study aims to improve our understanding of partner effects, mixture performance and the genetic architecture of species interactions in maize–bean intercropping.
