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.

Seeking farmer support to replace pesticides by mass trapping in Bangladesh

Picture copyright ICAR-NBAIR

The eggplant shoot and fruit borer is a major damaging pest in Asia. Most farmers control this pest by spraying insecticides every week. Researchers Nahar et al. observed from a participatory study that such a chemical method of control was not effective. In contrast, the use of pheromone traps reduced yield losses by 20-30% and cost less than conventional practice. The adoption of alternative techniques, however, is constrained by farmers’ knowledge of insect biology and ecology, and therefore requires support to farmers.

Cover crops with subterranean clover reduce the adoption of synthetic herbicides and fertilizers

Picture copyright Scavo et al.

Cover crops are gaining in popularity for their positive effects in agroecosystems, especially under organic farming and in low-input agriculture. Based on a 3-year field experiment, scientists Scavo et al. found that self-residing subterranean clover with the incorporation of dead mulches into the soil reduced weeds and increased the soil nitrogen. These results are useful for reducing the utilization of synthetic herbicides and mineral nitrogen fertilizers in Méditerranéenne orchards.

The key role of ley pastures in tomorrow’s cropping systems

Picture copyright Martin et al.

Diversification of cropping systems is a major way towards sustainable agriculture. Scientists Martin et al. recently reviewed the impacts of integrating ley pastures in cropping systems. Such pastures provide farmers with a wide range of services, including soil conservation, nutrient provision and recycling, soil water retention, and biological control of pests and weeds. Lay pastures contribute also other services to the society, such as water purification, climate regulation, habitat provision for conserving associated biodiversity, and forage production.

Estimating adoption and impacts of agricultural practices with satellite data

Picture copyright Iftikar, CIMMYT

New data sources improve the evaluation of agricultural management practices. Kubitza et al. reviewed the literature and found that satellite data have been used successfully to detect various agricultural practices in developing countries. However, only a few studies have used satellite data to estimate the yield impacts of agricultural practices and to estimate the impact beyond the biophysical sphere. Usage of satellite data in developing countries has yet produced technical studies but should now facilitate collaboration with economics.

Microbes help alleviating zinc and iron deficiencies in dietary food grains

Picture copyright Singh & Prasanna

Microorganisms play important roles in increasing micronutrient bioavailability to plants. Scientists Singh and Prasanna review the various strategies employed for the biofortification of Zn and Fe in dietary food grains. They emphasize the important role of soil-plant-microbe interactions in improving crop productivity, soil fertility, and translocation of micronutrients in crop plants. They reckon it is imperative to better integrate such microbial inputs into crop management practices.

A shared framework to use efficiently crop diversification benefits

Picture copyright Jenny Fischer, Thünen Institute of Organic Farming

Agricultural intensification has shaped uniform cropping systems and landscapes. Crop diversification may counteract such negative impacts and loss of biodiversity but presently, research lacks a shared understanding of diversification. Scientists Hufnagel et al. reckon that research approaches to crop diversification are too variable and inefficient. They propose a shared framework to compare, and profit from, crop diversification benefits.