Walnut trees strongly depend on arbuscular mycorrhizae for their mineral nutrition. In return, these fungi obtain from the trees, sugars and lipids to sustain their growth and reproduction. Scientists Mortier et al. surveyed 40 years of scientific literature on the relationships between arbuscular mycorrhizae and walnut tree roots. The root colonization process leads to enhanced seedling survival and quality. The knowledge of positive and negative feedbacks between walnut planting and the fungi allows developing sustainable walnut agroforestry systems.
Integrated Crop-Livestock Systems are nature-inspired food production systems, seeking sustainable intensification. They count on diversity and nutrient cycling to deliver ecosystem services, although their current fertilization practices follow a conventional per crop basis. Scientists Farias et al. evaluated several systems growing soybean in rotation with pastures for sheep. They showed that adopting a system fertilization strategy and integrating crops with livestock saved on fertilization, thereby decreasing costs and pollution while retrieving autonomy at the farm level.
Persistent malnutrition and rural poverty, environmental degradation, and loss of biodiversity are global challenges for food systems, aggravated by the growing consequences of climate change. Agroecological principles, when applied in context, generate transition pathways that transform agricultural and food systems to address these issues. Scientists Wezel et al. identified among these principles, four key entry points for systems transformation: diversity, circular and solidarity economy, co-creation and sharing of knowledge, and responsible governance.
Soil erosion rates are high in rainfed olive mountain plantations applying conventional practices, compromising, therefore, their long-term sustainability. Implementing sustainable soil management strategies is essential for hillslopes and low-fertility soils where plantations cover vast tracts of land. Researchers Durán et al. revealed potential environmental benefits of the organic system in controlling water erosion and improving soil health restoration compared to the conventional system.
Coffee plantation productivity is threatened by both climate change and decreasing revenues of growers. Scientists Piato et al. analyzed how growing robusta coffee under shade trees impacts coffee growth, yield, and quality. They found that the effects depend on tree age and the robusta clone tested. Whereas moderate shade can increase growth and yield, excessive shade may alter cup quality.
Citizen science promises an innovative approach to participation in research but its potential in agricultural research has not been systematically examined. Scientists van de Gevel et al. reviewed the literature and found that citizen science opens up four opportunities for creatively reshaping research: (i) new possibilities for interdisciplinary collaboration, (ii) rethinking configurations of socio-computational systems, (iii) democratization of science, and (iv) new accountabilities.
Legumes have a key role to play in agriculture transition towards greater sustainability, due to their ability to provide ecosystem services. However, choosing the right grain legumes to provide specific ecosystem services remains difficult because references are lacking for a diversity of species. Guinet et al. characterized and distinguished ten-grain legumes according to their ability to deliver contrasted nitrogen-related ecosystem services. Their study provides a rationale for choosing legumes species according to intended objectives and for adjusting N management in cropping systems.
Food security and environmental protection require optimizing crop N fertilization. Scientists Wang et al. reviewed studies on Chinese potato production to determine the optimal N-fertilization rate at a regional scale. The recommended rate improved N use efficiency and agronomic efficiency without sacrificing potato yield. These practices establish a reasonable trade-off between potato production and N-fertilizer management for the development of more sustainable agricultural systems.
It is a challenge to understand how on-farm diversity can be mobilized to design sustainable agricultural systems. Scientists Lurette et al. used a model to represents the diversity in the organization of several farms composing a territory in the South of France. They showed how diversity impacted farm performances, and how external inputs or subsidies impacted their sustainability. Pairing territory composition diversity with on-farm diversity will help in designing sustainable agricultural systems.
Improved tropical forages include annual/perennial grasses, herbaceous/dual-purpose legumes, and multipurpose trees/shrubs. They have been promoted in Sub-Saharan Africa to address food scarcity limiting smallholder livestock productivity. Scientists Paul et al. reviewed 72 studies, demonstrating tropical forages’ multiple benefits on livestock and food crop productivity, household income, and soil quality.