Farmer seed exchange is essential for food security because seed exchange maintains crop biodiversity and, in turn, biodiverse crops survive better climate changes and pest infection. However, actually we do not understand exactly how seed exchange networks induce crop diversity. A study by Pautasso explains why individual farmers do not cultivate all varieties present in a region or a village.
Canola is a major crop for food as canola oil, and energy as biodiesel. Many factors control the yield of canola, but there is actually little knowledge on the influence of the spatial arrangement of canola plants. Gan et al. shows that uniform canola stands increase seed yield by up to 32% at low-yielding sites and by up to 20% at the high-yielding sites, compared to non-uniform plant stands. Yields can thus be increased by more uniformity, regardless of environmental conditions.
Food security is increased and poverty is reduced in sub-Saharan African by cultivation of fruits and vegetables. However, up to 100% yield losses are due to insects and diseases. Misuse, overuse and use of unauthorized pesticides are common among small farmers. De Bon et al. presents solutions based on agroecology and integrated pest management (IPM) to reduce pesticide use. In particular ecological methods and good pesticide management should be taught to farmers and other stakeholders.
Rice is a major food worlwide. The cost of rice fertilisation using mined fertilisers such as nitrogen (N), phosphorus (P), and potassium (K) amounts to 30-35% of the cropping cost, and is still increasing. This issue could be solved by replacing mined fertiliser by biofertilisers that contain microbes helping the plant to grow, so-called ‘plant growth-promoting microorganisms’. The report by Rose et al. indeed show that inoculant biofertilizers can replace up to 52% of mined nitrogen fertiliser without loss of yield.
Producing safe food could be achieved in a sustainable way by changing agricultural practices. However, there is actually a lack of suitable methods and indicators that measure sustainability. This lack of knowledge is particularly deep at the farm level in poor countries that represent most food production worldwide. In addition, actual indicators are defined only by scientists, thus not taking into account essential farmer knowledge. Using participatory indicators designed with farmers Yegbemey et al. reveal weaknesses of maize cropping in Benin. This knowledge can be used to set up sustainable cropping practices.
Industrial coffee production has increased greenhouse gas emissions because many forests have been converted to lightly shaded or full-sun crops. Indeed the huge amounts of carbon stored in forest trees and soil are decomposed then released into the atmosphere as carbon dioxide (CO2) upon deforestation. There is therefore a need for more ecological coffee production systems. Van Rikxoort et al. have compared the climate impact of four arabica coffee systems: unshaded monoculture, shaded monoculture, commercial polyculture and traditional polyculture. The authors provide advices for climate-friendly coffee production.
Strawberry is delicious and a high-value crop grown worldwide. Strawberry diseases are commonly controlled by soil fumigation with toxic chemicals. Alternative control techniques are thus needed. The article by Domínguez et al. presents a new technique, named biosolarisation, that combine soil biofumigation and soil solarization. Soils were biofumigated with fresh chicken manure with or without Trichoderma, Brassica juncea pellets, sugar beet vinasse, or dried olive pomace. Soils were then solarised 30 days by covering with clear plastic mulch, thus allowing the sun to warm up and kill pests. Results show that strawberry yields were similar to higher than yields using classical chemical treatments. Biosolarization with fresh chicken manure is therefore a promising sustainable option for clean strawberry production.
Today half of the world population would not be alive without the 68 million tons of nitrogen (N) fertiliser applied to agricultural soils yearly. However, synthetic N has become too much of a good thing because most applied N is not used by crop plants and escapes to pollute groundwater as nitrates and atmosphere as nitrogen oxides. An alternative and cheap solution is to return plant residues to the soil, thus producing ‘natural’ N by plant residue decomposition. Chen et al. reviewed the effects of crop residues on soil N behaviour to better understand the mechanisms of transformation, and to predict farming practices that optimise natural fertilisation.
Agroforestry is the growing of crops and trees together. Mutual benefits of crops and trees can increase crop yields and food security. Agroforestry is also a solution for climate change because agroforestry stores more carbon into the soil, and, in turn, decrease atmospheric CO2, a greenhouse gas. The review article by Lorenz and Lal analyses the actual knowledge on the potential of agroforestry to store carbon in soils
Flavescence dorée is a serious disease that causes major yield losses for European viticulture. Flavescence dorée is still spreading in Europe despite mandatory controls using insecticides. Vine infection by Flavescence dorée is done by the association of a phytoplasma – a bacterial parasite – and the leafhopper Scaphoideus titanus. The only actual solution to avoid the disease is to control the leafhopper. Chuche and Thiéry review the biology and ecology of the S. titanus leafhopper to highlight potential ecological remedies. Innovative techniques include symbionts, mating disruption and push-pull strategies including antifeedants