Yields of organic and conventional agriculture have the same variability

Picture copyright Lesur-Dumoulin et al.

Organic agriculture seeks to reduce our reliance on non-renewable resources and to affect positively human health. However, its capacity to feed the growing world population is questioned. Scientists Lesur-Dumoulin et al. analysed an extensive dataset of yields from organic vs conventional horticulture and showed that in organic agriculture, yields are on average 10 to 32% lower than in conventional agriculture. Extreme yield reductions (>50%) are very unlikely and there is no evidence that organic agriculture gives more variable yields than conventional one.

Converting to organic viticulture makes management complex

Picture copyright Merot and Wery

Conversion to organic farming is a great challenge in vineyard systems, causing major changes in system structure and management. Agronomists Merot and Wery proposed six complexity indicators to assess modifications to cropping system structure and management during conversion. They demonstrate that conversion to organic viticulture increase the complexity of vineyard structure and management. These indicators can be extended to all agricultural systems to diagnose the impact of organic farming conversion.

Organic chocolate production saves energy

Picture copyright PEREZ NEIRA

The industrialization of agriculture has often led to lower efficiency, pollution and greater dependence on non-renewable energy. Organic agriculture and traditional agriculture are thus potential alternatives. Agronomist Pérez Neira studied the energetic and economic behavior of cacao in traditional, semi-intensive traditional, technified and organic farms in Ecuador. Results show that well-managed organic farms improve energy efficiency by comparison with technified or semi-intensive management strategies, and also improves the economic performance.

Less plough same yield in organic farms

Picture copyright COOPER et al.

Conservation agriculture embraces the three principles of minimal soil disturbance, maximum residue cover and diverse crop rotations. However, organic farmers are reluctant to give up their ploughs due to concerns about weeds, crop disease and nutrient supply. Agronomists Cooper et al. review data from organic experiments and found that yields were not as negatively affected by reduced tillage intensity as expected.

Rice-duck farming, a win-win strategy

Picture copyright PIRDASHTI et al.
Picture copyright PIRDASHTI et al.

Organic farming aims at reducing the use of mineral fertilisers and pesticides, and producing safe and tasty food. Agronomists Pirdashti et al. explain that growing ducks in rice field has many benefits such as weed control and fertilisation by ducks and high quality rice and duck meat.


Organic farming of cereal-legume intercrops for food security

Agriculture faces two major issues worldwide, producing safe food without the use of toxic pesticides, and producing more food to meet the projected population increase of 9 billion by 2050. Ecological intensification is a promising solution because ecosystem services such as the use of natural enemies to kill undesired pests is a safe alternative to pesticides. Agonomists Bedoussac et al. reviewed the results of 58 organic farming experiments of cereal-grain legume intercropping in Europe. They found that intercropping gives higher yields, protein and money that sole crops.


Four strategies to grow organic apples

Organic farming should provide safe food without using harmful pesticides. As a consequence farmers need alternative techniques to control pests. A survey of 24 organic apple farms in France by agronomists Marliac et al. reveals four control techniques: 1) the ecologically intensive technique that favours natural enemies of pests, 2) the substitution technique using pesticides, 3) the technological technique using for instance exclusion nets, and 4) the integrated techniques using a variety of previous techniques.


Cover crops and mulching decrease greenhouse gas emissions of fruit tree orchards

Fruit tree orchards should be climate friendly because atmospheric carbon is stored during long periods of time in trees. Orchards also produce woody renewable energy. However orchard soils, which store carbon, are often eroded under the Mediterranean climate. Agronomists Aguilera et al. show that organig farming techniques such as cover cropping and pruning mulching should offset greenhouse gas emissions, thus leading to carbon neutral crop products.


Organic farming of herbaceous crops produces less greenhouse gas emissions

Organic farming recycles local plant residues and compost to fertilize soils, whereas conventional agriculture uses mineral fertilizers that are mined then transported over long-distances. Therefore organic farming should emit less greenhouse gases. However the lower yields of organic farming may compromise the emission balance on a product basis. Agronomists Aguilera et al. observed that emissions from herbaceous crops in Spain were lower under organic farming both on an area basis and on a product basis, with the exception of rice due to higher methane emissions.