Cereal-cowpea intercropping for sustainable intensification in sub-Saharan Africa

Picture copyright CIMMYT

Intercropping is a common sustainable practice that improves land productivity in smallholder farms in sub-Saharan Africa. Namatsheve et al. reviewed the main cereal-cowpea intercropping systems, comprising maize, sorghum, and pearl millet. Intercropping increased land productivity by 25-40% compared to monocropping systems, with cowpea intercropped being able to contribute significant amounts of nitrogen to the system. The authors suggest several ways to improve these systems.

Energy flow analysis in farm systems

Energy plays a key role in farm systems and many approaches are available to compute energy flows in these systems. Hercher-Pasteur et al. recently analyzed ten approaches and evaluated their ability to address sustainability issues. They showed that a systemic/circular perspective helps to assess farm systems as an agro-ecosystem. They highlighted the importance of managing the internal circulation of flows, the reuse of biomass, and the soil organic matter in this assessment.

Silphium domestication benefits from multiple crop improvement methods

Picture copyright INRAE and Springer-Verlag France SAS, part of Springer Nature

Silphium species are perennials able to optimize water use, reduce erosion, and deposit more carbon than annual crops while producing food. Their domestication is often slowed by inflexibility in how plants mate to produce seeds. Scientists Reinert et al. revealed that Silphium species self-pollinate and cross-pollinate, even among closely related species. This provides breeders with the flexibility to introduce new genes and enhance their expression.

Improving rice quality along the value chain

Scientists Prom-u-Thai and Rerkasem recently reviewed opportunities and limits in rice quality and value improvements. They showed that quality improvement through breeding differentiated mega-modern high-yielding rice varieties from others. Rice value has increased with grain breakage reduction at harvest and postharvest. They reckoned that sorting paddy from Asia’s small farms into quality- and price-differentiated segments of the value chain is a useful guideline for rice quality upgrading.

A farmer participatory approach to improve groundwater quality

French and EU policies struggle to promote the restoration of groundwater quality by encouraging farmers to change their practices. Scientists Richard et al. developed a farmer-to-farmer suggestion-based method for improving farm management from economic, social, and environmental viewpoints. Such a method proves interesting and viable to promote sustainable farming practice and implement groundwater-friendly farm management.

Valuating big data provided by crop trials

Picture copyright Bioversity International/L. Machida

Crop scientists spend much of their time and resources on field trials, growing and measuring crop plants. But these expensive data are often used only once and then forgotten. A review by Brown et al. identifies a number of constraints, including heterogeneous data formats and a lack of standardized methods across trials. They outline how new methods could help data synthesis and gain new insights about patterns of variety suitability and interactions with growing environments.

Control rather than eradicate weeds

Picture copyright Rothamsted Research

The intensive use of herbicides and tillage to eradicate weeds from fields leads over time to biodiversity loss, soil erosion, health risks, and herbicide resistance. In a recent review, researchers MacLaren et al. suggest to regulate rather than eradicate weeds, in order to suppress problematic weeds while fostering weed diversity, able to sustain ecosystem services. This could be achieved by reducing the intensity of weed control, but increasing the strategic use of the crop, livestock, nutrient, and management diversity on farms.

Exploiting the potential of vegetable grafting in sub-Saharan Africa

Picture copyright Elias Shem, The World Vegetable Center (Arusha, Tanzania)

Grafting, i.e. joining a scion (plant upper part) and a rootstock (plant lower part) is a worldwide developing horticultural technique useful to overcome various soilborne diseases and stresses. In sub-Saharan Africa, grafting is widely used nowadays, in commercial orchards (avocado, mango, or citrus) but for vegetables, it remains largely unknown. Scientists Nordey et al. explored the potential of vegetable grafting to increase and secure crop productions in the challenging environments of sub-Saharan Africa and attempted to identify factors hindering such practice.

Planting date, landscape composition and field management alter potyvirus infection in maize

Picture copyright Clemente-Orta et al.

Viruses limit maize production around the world. Scientists Clemente-Orta et al. developed predictive models at variable spatial scales for explaining the incidence of two closely related potyviruses: maize dwarf mosaic virus and sugarcane mosaic virus at three different landscape scale. They showed that early planting, the management of edges, and the presence of non-crop habitats are key factors of virus incidence.

Assessing agroforestry interventions in Northwest Vietnam

Picture copyright Do et al.

Agroforestry can reduce poverty and improve food security while addressing land degradation and delivering ecosystem services. Agroforestry systems, however, are highly complex rendering their long-term performance difficult to anticipate. Do et al. assessed several agroforestry options in the highlands of Northwest Vietnam, using decision analysis and probabilistic modeling. They calculated the benefits of these agroforestry systems but forecast important uncertainties in the decision-making process.