Joséphine Peigné

Agroecological practices for sustainable agriculture. A review

The forecasted 9.1 billion population in 2050 will require an increase in food production for an additional two billion people. There is thus an active debate on new farming practices that could produce more food in a sustainable way. Here, we list agroecological cropping practices in temperate areas. We classify practices according to efficiency, substitution, and redesign. We analyse their advantages and drawbacks with emphasis on diversification. We evaluate the potential use of the practices for future agriculture. Our major findings are: (1) we distinguish 15 categories of agroecological practices (7 practices involve increasing efficiency or substitution, and 8 practices need a redesign often based on diversification). (2) The following agroecological practices are so far poorly integrated in actual agriculture: biofertilisers; natural pesticides; crop choice and rotations; intercropping and relay intercropping; agroforestry with timber, fruit, or nut trees; allelopathic plants; direct seeding into living cover crops or mulch; and integration of semi-natural landscape elements at field and farm or their management at landscape scale. These agroecological practices have only a moderate potential to be broadly implemented in the next decade. (3) By contrast, the following practices are already well integrated: organic fertilisation, split fertilisation, reduced tillage, drip irrigation, biological pest control, and cultivar choice.

How organic farmers practice conservation agriculture in Europe

The interest of organic farmers in adopting conservation agriculture principles, including minimal soil disturbance, permanent soil cover and crop rotation has been growing since the early 2000s. However, currently there is no network for organic farmers practicing conservation agriculture, and a lack of knowledge on how organic farmers implement conservation agriculture in practice. Consequently, few technical references are available for organic farmers when they start applying conservation agriculture practices, in particular on controlling weeds without the use of herbicides. The main objectives of this study were: (1) to explore the diversity of conservation agriculture techniques (i.e., reduced tillage, no-tillage and green manures) practiced among European farmers, and (2) to identify farmers’ main strategies for implementing conservation agriculture and the agronomic and environmental factors that determine these strategies. Strategies were identified by analyzing survey results on: (1) the type and degree of use of conservation agriculture practices by farmers, and (2) the effects it produces in terms of soil disturbance and soil cover (low, medium and high). We carried out a survey of 159 European organic farmers and collected 125 data sets on management of winter-sown crops. Among the conservation agriculture practices, reduced tillage was used by 89%, no-tillage by 27% and green manure by 74% of the 159 interviewed farmers. Green manures were more frequently used in northern Europe than in the south (below 45°N). Most of the farmers used crop rotations, with a mean duration of 6 years. A wide diversity of conservation agriculture practices were used, with farmers rarely using all three techniques (no-till, reduced till and green manures) within one system. The range of practices was grouped into five strategies ranging from intensive non-inversion tillage without soil cover to very innovative techniques with no-tillage and intercrops. The five strategies for conservation agriculture could be grouped into two larger categories based on weed control approach: (1) intensification of the mechanical work without soil inversion or (2) biological regulation of weeds with cover crops. The diversity of strategies identified in this study shows that organic farmers use innovative approaches to implement conservation agriculture without herbicides. This studys findings will help organic farmers to experiment with innovative practices based on conservation agriculture principles and also benefit conventional farmers who use conservation agriculture practices and would like to reduce or eliminate the use of herbicides.

Farmers and agronomists design new biological agricultural practices for organic cropping systems in France

New organic cropping systems are needed to keep pace with the growing demand for organic food. Those systems should ideally give more yield and safe for the environment. Current innovations such as non-inversion tillage with cover crops are promising, but investigations usually do not take farmers view into account. Therefore, research work should include farmer participation to maximize success. We present here a method to help farmers in designing innovative cropping systems. This method involves several design workshops with farmers. The first steps of the method foster creativity by changing ways in which farmers thought and worked. The final steps of the method facilitated learning. Participatory tools are used to exchange views and knowledge. System prototypes were developed. The method was applied using groups of six and seven farmers from two French regions. The farmers generated 14 system prototypes. We found that system prototypes differed radically from current practices because prototypes are based on biological rather than mechanical methods. Indeed, cover crop use was almost four times more frequent in prototypes than in current systems. Moldboard plowing and mechanical weeding frequencies were, respectively, two and eight times lower. The main benefits of our method are (1) the involvement of volunteer farmers in the design process, (2) the combination of farmer knowledge and scientific knowledge, and (3) the use of various methodological supports.

Wheat yield and quality as influenced by reduced tillage in organic farming

Organic farmers are interested in soil conservation by reduced tillage, techniques well known in conventional agriculture to protect soil quality and limit labor time and energy costs. However, organic farming and reduced tillage can modify weeds, soil structure, and thus soil nitrogen (N) mineralization which strongly influences wheat yield and quality. The main objectives of this study were to analyze how reduced tillage applied to organic wheat influenced (1) grain yield, protein concentration, and weed infestation; (2) deoxynivalenol (DON) contamination on grain; (3) technological quality parameters such as dry gluten, zeleny index, falling number, and gluten index; (4) protein composition (F1, F2, F3, F4, and F5 fractions, and UPP, gliadin/glutenin ratio); and (5) baking test. For this purpose, we analyzed five site-years of data from winter wheat crops where mouldboard ploughing and reduced tillage were compared in three experimental trials (two in France and one in Switzerland). Main results concern wheat yields: the effect of reduced tillage on wheat yield was influenced by several factors such as weed competition. No significant increase in mycotoxin content (DON) due to reduced tillage was detected. Contamination with DON was always below the European threshold for human consumption. The technological quality parameters were less affected by the tillage treatments than grain yield: protein content, gluten index, zeleny index, and falling number showed on average no significant difference between treatments although the protein composition was slightly different. The main results of this study are that the effect of reduced tillage on grain yield depends very much on soil type, weather conditions, and time after conversion, whereas there is only minor impact on wheat quality. This is in contrast to the hypothesis that reduced tillage under organic farming will cause problems in baking quality.

Organic Bread Wheat Production and Market in Europe

This chapter is a first attempt to analyse bottlenecks and challenges of European organic bread wheat sector involving technical, political and market issues. From 2000, the organic grain market has largely increased in Western Europe. To balance higher consumer demand there is a need to increase organic production by a new transition and technical improvement. Bread wheat is grown in a variety of crop rotations and farming systems where four basic organic crop production systems have been defined. Weeds and nitrogen deficiency are considered to be the most serious threat inducing lowest grain yield under organic production. The choice of cultivar, green manure, fertilization and intercropping legumes – grain or forage – are efficient ways to obtain high grain quality and quantity.

Organic farmers’ motivations and challenges for adopting conservation agriculture in Europe

Conservation agriculture and organic farming are considered as promising sustainable agricultural system for producing food, while minimizing environmental impacts. Despite an increasing number of experimental data on organic conservation practices and various studies dealing with the adoption of conservation agriculture by farmers, none of those studies have specifically addressed conservation agriculture adoption under organic conditions in Europe. We carried out a survey with 159 farmers located in 10 European countries. These farmers had applied at least two of the following conservation practices: (i) no-tillage, (ii) reduced tillage and (iii) green manures. Each farmer assessed socio-economic, agronomic and environmental motivations and problems for each conservation practice, using a Likert scale. For each conservation practice, we ranked motivations and problems and carried out a principal component analysis, followed by clustering to identify groups of farmers. Independent of the conservation practices, the most important motivations were related to soil fertility preservation and challenges were mainly linked to crop management, machinery and yield performances. For all conservation practices, we identify three groups of farmers that shared the same type of motivations and challenges across Europe: “soil conservationists,” “agro-technically challenged farmers,” and “indifferent farmers.” Soil conservationist farmers were strongly motivated by soil preservation and minimizing environmental impacts. Agro-technically challenged farmers mainly expressed agronomic problems and challenges. There were no clear effects of location or farm characteristics explaining these attitudes, but they depended on farmers’ environmental concerns and beliefs. The study demonstrated that research priorities should address agronomic problems caused by the adoption of conservation practices in organic farming, weed control in particular.

Organic farmers in Europe: motivations and problems for using conservation agriculture practices

The interest of organic farmers for adopting conservation agriculture practices is currently growing. But, there are few technical and scientific references available for organic farmers when they start applying conservation agriculture practices. The main objectives of this study are (1) to explore the diversity of crop management practices using conservation agriculture methods among European farmers, and (2) to identify main farmers’ strategies. We carried out a survey of 159 farmers located in 10 European countries. Data were analysis to identify groups of farmers that share the same type of spring and winter crop managements. Organic farmers in Europe show very diverse crop management. The high diversity of crop management can be described by two main strategies: ‘low soil cover’ and ‘soil conservation’ strategy. Distinct geographical distribution of both strategies suggests that applicability of conservation agriculture practices is strongly context oriented.Conserving and improving the fertility and quality of the limited soil resource to produce food, feed and fibre has always been the key to organic farmers’ management practices. This issue is also addressed in conservation agriculture systems that give up on soil tillage (no-tillage) or reduce tillage intensity, but often build on the extensive use of herbicides and mineral fertilizers. Both systems show advantages for soil quality (Holland, 2004; Mader et al., 2002) and therefore their combination is promising and may provide better soil quality. Challenges of introducing noor reduced tillage systems into organic farming are increased weed pressure, retarded mineralization of nutrients that both may lead to reduced crop yield (Peigne et al., 2007). Pioneer farmers have developed solutions and new machinery to be applicable in organic farming systems. Comparisons of reduced tillage to the traditional plough system have started on farms and systematic research started a decade ago. It was the aim of our research activities, accomplished within the frame of the European network TILMAN-ORG (www.tilman-org.net), to evaluate changes in soil carbon stocks and biological soil fertility parameters in soils from European field trials that compared reduced primary soil tillage options with standard procedures (mainly plough). The selected sites represent a geoclimatic gradient from the North-East to the South-West. The hypothesis was that reduced tillage is enhancing the stratification of soil organic matter, soil microbial biomass and activity, and is changing microbial community structure and microbial functions.Conservation agriculture and organic farming are currently considered as environmentally friendly options for producing food. This study explores the motivations and problems of organic European farmers that apply at least two conservation techniques: (i) no-tillage, (ii) reduced tillage and/or (iii) green manure. We carried out a survey with 159 farmers located in 10 European countries. Data were analysed with a principal component analysis followed by clustering to identify groups of farmers with similar motivations and problems. The most important motivations are related to soil preservation and problems are mainly linked to agronomic conditions and crop management. There are three groups of farmers that share the same type of attitude: “atypical farmers”, “soil conservationists” and “agro-technically challenged farmers”. Further research may address in priority agronomic problems, such as weed infestation, caused by adoption of conservation agriculture in organic agriculture.Environmental concerns are pushing organic farmers to substitute ploughing with reduced tillage but weed management under reduced tillage can be troublesome. One objective of the TILMAN-ORG Project is to improve weed management with reduced tillage ± cover crops without reducing weed community diversity. This paper reports results obtained in 2012 in 13 long-, mid-, and short-term trials scattered across Europe including winter cereals, maize, grain pea, potato, sunflower and grass/clover or legume leys. Longand midterm experiments showed higher weed abundance under reduced tillage but usually without reduced crop yield. Short-term trials showed that reduced tillage system may be troublesome to manage right after the conversion from ploughing, due to higher abundance of weeds and volunteer crops and reduced yield. Interestingly, there was no overall consistent relationship between weed diversity, always higher under reduced tillage, and crop yield.

Diversity of Conservation Agriculture Practices Among European Organic farmers

The interest of organic farmers for adopting conservation agriculture practices is currently growing. But, there are few technical and scientific references available for organic farmers when they start applying conservation agriculture practices. The main objectives of this study are (1) to explore the diversity of crop management practices using conservation agriculture methods among European farmers, and (2) to identify main farmers’ strategies. We carried out a survey of 159 farmers located in 10 European countries. Data were analysis to identify groups of farmers that share the same type of spring and winter crop managements. Organic farmers in Europe show very diverse crop management. The high diversity of crop management can be described by two main strategies: ‘low soil cover’ and ‘soil conservation’ strategy. Distinct geographical distribution of both strategies suggests that applicability of conservation agriculture practices is strongly context oriented.Conserving and improving the fertility and quality of the limited soil resource to produce food, feed and fibre has always been the key to organic farmers’ management practices. This issue is also addressed in conservation agriculture systems that give up on soil tillage (no-tillage) or reduce tillage intensity, but often build on the extensive use of herbicides and mineral fertilizers. Both systems show advantages for soil quality (Holland, 2004; Mader et al., 2002) and therefore their combination is promising and may provide better soil quality. Challenges of introducing noor reduced tillage systems into organic farming are increased weed pressure, retarded mineralization of nutrients that both may lead to reduced crop yield (Peigne et al., 2007). Pioneer farmers have developed solutions and new machinery to be applicable in organic farming systems. Comparisons of reduced tillage to the traditional plough system have started on farms and systematic research started a decade ago. It was the aim of our research activities, accomplished within the frame of the European network TILMAN-ORG (www.tilman-org.net), to evaluate changes in soil carbon stocks and biological soil fertility parameters in soils from European field trials that compared reduced primary soil tillage options with standard procedures (mainly plough). The selected sites represent a geoclimatic gradient from the North-East to the South-West. The hypothesis was that reduced tillage is enhancing the stratification of soil organic matter, soil microbial biomass and activity, and is changing microbial community structure and microbial functions.Conservation agriculture and organic farming are currently considered as environmentally friendly options for producing food. This study explores the motivations and problems of organic European farmers that apply at least two conservation techniques: (i) no-tillage, (ii) reduced tillage and/or (iii) green manure. We carried out a survey with 159 farmers located in 10 European countries. Data were analysed with a principal component analysis followed by clustering to identify groups of farmers with similar motivations and problems. The most important motivations are related to soil preservation and problems are mainly linked to agronomic conditions and crop management. There are three groups of farmers that share the same type of attitude: “atypical farmers”, “soil conservationists” and “agro-technically challenged farmers”. Further research may address in priority agronomic problems, such as weed infestation, caused by adoption of conservation agriculture in organic agriculture.Environmental concerns are pushing organic farmers to substitute ploughing with reduced tillage but weed management under reduced tillage can be troublesome. One objective of the TILMAN-ORG Project is to improve weed management with reduced tillage ± cover crops without reducing weed community diversity. This paper reports results obtained in 2012 in 13 long-, mid-, and short-term trials scattered across Europe including winter cereals, maize, grain pea, potato, sunflower and grass/clover or legume leys. Longand midterm experiments showed higher weed abundance under reduced tillage but usually without reduced crop yield. Short-term trials showed that reduced tillage system may be troublesome to manage right after the conversion from ploughing, due to higher abundance of weeds and volunteer crops and reduced yield. Interestingly, there was no overall consistent relationship between weed diversity, always higher under reduced tillage, and crop yield.