Increasing crop trait diversity in oilseed rape (OR, Brassica napus L.) cropping systems by introducing frost-sensitive legume species could improve weed suppression and crop productivity. Intercrops and sole crops were compared over two years in the field in Western France. Winter OR was intercropped simultaneously with either spring faba bean (Vicia faba L.) or common vetch (Vicia sativa L.) in a row replacement design without herbicides. Each species was sown at 50% of the recommended sole crop density in alternate rows. Due to the high values of faba bean aboveground traits (height, leaf area, and biomass) and the strong competitive ability for soil N of OR, both species appeared complementary in resource utilization, and thus less soil N and light were available for weeds. The OR–faba bean intercrop was able to reduce weed biomass by 41% compared to the OR–common vetch intercrop. Furthermore, growth and competitive ability of OR for soil N were increased when intercropped with faba bean. Both grain yield and number per plant were three times higher in OR–faba bean intercrops compared to OR sole crops. Under high weed infestation, the presence of faba bean with OR reduced weed aboveground biomass by 35% and weed N accumulation by 11% compared to the OR sole crop. No change was observed in the weed community composition. We observed that a level of aboveground biomass greater than 2 t ha⁻¹ and a soil N uptake at approximately 80 kg ha⁻¹ was needed to reduce biomass and N content of weeds.

Soybean (Glycine max (L.) Merr.) may contribute to the agro-ecological transition of cropping systems in Europe, but its productivity is severely affected by summer drought. The crop is mainly grown in southern and continental parts of Europe, whereby increasing drought and heat waves are expected in the near future. Agronomic strategies, such as early sowing, require cultivars with enhanced early plant growth traits under suboptimal conditions. Moreover, efficient water uptake by root delays dehydration and promotes drought avoidance. In general, changes in root morphology and root architecture are important pathways for plant adaptation to water stress conditions. This paper reviews the cultivar differences in soybean for root morphological and architectural traits especially during early growth stage. Previous works reported cultivar differences for root traits in soybean but they did not deal with cultivars commonly grown in Europe on which little information is available to date. Genotypic differences in available early-stage root traits can be used as a framework to design soybean ideotypes less vulnerable to drought. To this aim, high-throughput phenotyping supported by digital methods and crop modelling offer new avenues for the exploration of target root traits involved in drought avoidance.

Cover crops, sown between cash crops to provide ecosystem services, contribute to sustainability but present challenges related to the use of environmental resources out of the main cropping season. This dataset gathers the results of 37 field experiments related to cover crops, whether grown in sole crops or in mixtures, conducted in France over 19 years. It compiles quantitative data from field measurements and laboratory analyses on 33 species among five botanical families, along with information on technical management and climate conditions, providing a valuable resource for assessing cover crops performance.

Accroître la compétitivité des cultures vis-à-vis des adventices est un levier essentiel pour concevoir des systèmes de culture moins dépendants des herbicides. Les légumineuses sont des espèces majeures pour diversifier les systèmes mais elles sont réputées peu compétitives vis-à-vis des adventices. Cependant la variabilité entre espèces en particulier pendant la phase précoce a été peu explorée. Ce travail vise à i) étudier, via deux expérimentations en rhizotrons en serre, les traits impliqués dans la croissance et l’acquisition d’azote (N) en début de cycle chez une gamme d’espèces de légumineuse et les conséquences sur la compétition légumineuse-adventice et à ii) quantifier au champ l’intérêt d’associations légumineuse-non légumineuse (colzalégumineuses, maïs-légumineuses pérennes, la légumineuse étant plante de service) sur la croissance et la composition de la flore adventice. Nous montrons qu’il existe une variabilité entre espèces de capture d’N en début de cycle en lien avec les réserves azotées de la semence et l’exploration racinaire. La croissance et l’acquisition d’N de l’adventice sont impactées différemment selon l’espèce de légumineuse pendant la phase précoce. Les essais au champ montrent l’intérêt de combiner des espèces aux traits complémentaires pour l’utilisation des ressources conduisant à un meilleur contrôle des adventices tout en maintenant la productivité de la culture. Cette étude montre aussi que la composition de la flore est modifiée en fonction de la légumineuse insérée dans le système en lien à la fois avec les traits des légumineuses et les traits de réponse des adventices.