Marc Tchamitchian

French National Institute for Agriculture, Food, and Environment (INRAE) | INRAE · Unité de Recherche Écodéveloppement

Les bénéfices de la biodiversité fonctionnelle, notamment en terme de lutte contre les ravageurs, font l'objet de débats entre les praticiens et on sait peu de choses sur les pratiques et les motivations des agriculteurs pour favoriser cette biodiversité. Nous avons supposé que l'utilisation de méthodes de suivi aiderait les agriculteurs à mieux ap...

Crop losses from pests threaten global food security and safety. In the last six decades, pest control using chemical pesticides has resulted in important yield gains per unit area, worldwide. However, the long-term sustainability of chemical pest control has been increasingly thrown into doubt due to the negative impact on human health, biodiversi...

En novembre 2018, l'ITAB (Institut de l’agriculture et de l’alimentation biologiques) et l’INRA (Institut national de la recherche agronomique) ont organisé un séminaire transdisciplinaire pour : i) partager les enjeux associés à la gestion des sols dans les systèmes en Agriculture Biologique (AB), ii) définir collectivement les principales questio...

In response to the sustainability issues that agriculture faces in advanced economies, agroecology has gained increasing relevance in scientific, political, and social debates. This has promoted discussion about transitions to agroecology, which represents a significant advancement. Accordingly, it has become a growing field of research. We reviewe...

Crop losses from pests threaten global food security and safety. In the last six decades, pest control using chemical pesticides has resulted in important yield gains per unit area, worldwide. However, the long-term sustainability of chemical pest control has been increasingly thrown into doubt due to the negative impact on human health, biodiversi...

The role of functional biodiversity for favouring natural regulation and reducing pesticide use in fruit production is generally acknowledged. Although a number of farmers attempt to favour biodiversity through different strategies (e.g. diversified hedges, nesting boxes), they often lack means to evaluate how their actions contribute in practice t...

The scientific roots of organic systems are anchored in the four principles of IFOAM – Organics International: ecology, health, fairness, and care. Scientific skills are needed for the continuous improvement of organic food, systems, and culture. The Forum invited researchers to share their work in the following five themes, with a special focus on...

Variabilité du contexte de production, pertes de colonies d'abeilles : les exploitations apicoles font aujourd'hui face à différentes problématiques environnementales comme socio-économiques. Dans ce contexte, le projet DURAPI a visé à élaborer un cadre d'évaluation de la durabilité de ces exploitations, à travers une démarche participative qui a i...

Mixed fruit tree and vegetable (MFV) farms correspond to the joint production of fruit trees and vegetable crops. In temperate regions, this emerging farming system is a potentially attractive land use to foster the diversification of agricultural systems. However, these systems combine two productive and labor-intensive enterprises (orchard and ma...

Facing the challenge of the ecological transition of agriculture, biodiversity opens new avenues to enhance ecological interactions and reduce chemical input dependency. Designing biodiversity-based agrosystems requires an agroecological approach that combines key principles: exploring a wide range of concepts and solutions, adopting systemic reaso...

The need to redesign more sustainable agricultural systems able of producing more, especially through inter-cropping or agroforestry, cannot be achieved without taking into account the essential aspect of production variability. Yet, although many studies have focused on the effect of intercropping on overall production, the particular issue of pro...

Keywords: Apiculture Beekeeping Forage resource management Adaptive capacity Participatory design Multicriteria assessment A B S T R A C T Beekeeping is a long-standing production of livestock, which currently faces several technical and economic challenges such as high colony losses and highly variable honey yields. While the sustainability of cur...

Co-design and experiment of two fruit agroforestry systems grown in organic farming The VERtiCAL research project focused from 2013 to 2018 on the spatial and temporal diversification of fruit tree systems as a relevant mean for reducing pesticide use. The project resulted in the design and assessment of two fruit agroforestry systems (AFS), called...

Description of the subject. A system approach based on co-design and experimental field evaluation of cropping systems (CSs), combining technical and varietal innovations, has been implemented for sustainable management of root-knot nematodes (RKN) in Mediterranean sheltered vegetable systems. Objectives. Cropping systems combining genetic resistan...

À l'échelle d'une exploitation apicole, la capacité d'adaptation est liée à différents aspects du fonctionnement : aux pratiques de gestion du cheptel, à des choix de commercialisation ou d'organisation. Cette capacité d'adaptation contribue à la durabilité de l'exploitation en lui permettant de composer avec un contexte variable, mais constitue ég...

In agricultural sciences, it is frequently stated that diversified systems are more likely to cope with risks, but rarely demonstrated in a quantitative way. On the theoretical perspective, risk reduction based on asset diversification is a well studied mechanism in economics that has been formalized in the Modern Portfolio Theory (MPT). In this pa...

The concept of sustainability in agriculture has been translated into a range of operational evaluation frameworks at territory, farm or production system level. However, these frameworks are not adapted to beekeeping farms: what then can be called "sustainability" in the case of beekeeping farms? Which components of the apicultural system manageme...

In a context of a redefinition of farming system, innovative cropping systems have arose in the recent decades. Among them, diversified horticultural systems show a growing interest in Europe, especially among new entrants into farming. One of the main motivations for farmers to grow simultaneously a variety of vegetables and fruits is to reduce th...

The Organic market, cultivated surfaces and numbers of operators are growing fast (though surfaces grow more slowly). Organic products are based on agricultural and processing practices that avoid chemicals and that emphasize mechanical and biological operation. A strict regulation and independent certification bodies oversee those practices and th...

While much research has been devoted to analyze the benefits of intercropping and agroforestry systems on yield, through the concept of Land Equivalent Ratio, little literature is available on the benefits of such systems for reducing yield variability. In the present study, we intend to introduce the notion of yield variability in the Land Equival...

Résumé Le marché, les surfaces (plus lentement) et le nombre d’opérateurs Bio sont en forte croissance. Les produits Bio sont issus de pratiques agricoles et de transformation évitant les intrants chimiques et privilégiant les interventions mécaniques ou biologiques. Ces pratiques, tout comme la commercialisation, sont strictement encadrées par une...

Heuristic is one of the important techniques designed to find quickly good feasible solutions for hard integer programs. Most heuristics depend on a solution of the relaxed linear program. Another approach, Lagrangian relaxation offers a number of important advantages over linear programming [4], namely it is extremely fast for solving large proble...

To most effectively integrate research across scales and disciplines, long-term system experiments (LTSE) can serve as a valuable tool in agroecological studies. In this paper, we discuss the role of LTSE in understanding agroecosystem function, as well as components to effective design these studies to further the implementation of agroecological...

(Français) Pour concevoir et mettre en oeuvre des systèmes de production agroécologiques, les agriculteurs s’appuient sur un panel de connaissances (scientifiques, locales, expertes …) relatives à leurs milieux naturels et leurs fonctionnalités. Ils mobilisent un ensemble de pratiques, produits, méthodes et technologies qui valorisent la biodiversi...

This paper reviews the recent development of the scientific, legislative, economic and environmental aspects of plant organic farming. The impact of organic farming on biodiversity and soil fertility is discussed in comparison with conventional systems. A significant barrier for wide application and future development of organic farming is the exis...

Ce numéro est constitué d'articles issus du colloque CIAg "Une approche agro-écologique de la production végétale en Guyane", organisé le 23 octobre 2017 à Macouria en Guyane. Présentations et Vidéos du colloque disponibles (cf. "session 3 partie 2" pour cette communication).

L’humanité est confrontée à des défis d’envergure face auxquels l’agriculture va jouer un rôle essentiel. L’Agriculture Biologique (AB), souvent présentée comme un modèle de mise en œuvre des principes de l’agroécologie, peut-elle avoir une place prépondérante dans ce contexte ? Ce texte vise à répondre à la question des performances globales de l’...

Mixed fruit-vegetable cropping systems are a promising way of ensuring environmentally sustainable agricultural production systems in response to the challenge of being able to fulfill local market requirements. Indeed, they combine productions and they make a better use of biodiversity. These agroforestry systems are based on a complex set of inte...

Experimental Systems and Co-Desig

Combinations of varietal and technical innovations for the sustainable and integrated management of root-knot nematodes: the GEDUNEM project

Fresh produce has been a growing cause of food borne outbreaks world-wide prompting the need for safer production practices. Yet fresh produce agrifood systems are diverse and under constraints for more sustainability. We analyze how measures taken to guarantee safety interact with other objectives for sustainability, in light of the diversity of f...

The web-based platform "EBIO-Network" (European Biodiversity Orchards Network), created within the framework of the CoreOrganic plus project EcoOrchard, will provide an interactive communication tool between stakeholders in European organic fruit production at different levels (practice, science, advisory etc.). The we bsite will offer the opportun...

In the second half of the twentieth century, the agricultural production of the occidental world has rapidly increased, thanks to an integrated R&D scheme based mainly on three pillars, genetic improvement, adequate if not excessive nutrient supply, pest and disease control, the two last pillars being achieved by an important input of chemicals. Th...

This paper details this evolution of the French R&D system devoted to Organic Farming highlighting its differences to the system in place for conventional agriculture. It shows how integration in this knowledge system has increased, and analyzes under which pressures and initiatives this integration happened. Finally, the links between this system...

Plant protection spray treatments may expose non-target organisms to pesticides. In the pesticide registration procedure, the honey bee represents one of the non-target model species for which the risk posed by pesticides must be assessed on the basis of the hazard quotient (HQ). The HQ is defined as the ratio between environmental exposure and tox...

Feeding a growing population and ensuring food security whilst protecting ecosystems and natural resources are crucial priorities in times of global changes. Agroecology promotes innovative drivers of change for a smart agriculture that meets the specifications of ecological transition. Managing soil interactions offer largely unexplored potential...

The current restrictions on the use of chemical nematicides have contributed to increased root-knot nematodes (Meloidogyne spp.) problems in horticultural crops. In this context, plant resistance (R) appears as the most effective method of control, but the restricted number of cultivated vegetable species with root-knot nematode R-genes available (...

The aim of this work was to study case studies of a modified biological simulator (TOMGRO) in greenhouse tomato crop during winter period. The modified biological simulator (TOMGRO) that was used for case studies of the experiment has been developed and validated according the cultivation technique and the needs of the Mediterranean growers and the...

Feeding a growing population and ensuring food security whilst protecting ecosystems and natural resources are crucial priorities in times of global changes. Agroecology promotes innovative drivers of change for a smart agriculture that meets the specifications of ecological transition. Managing soil interactions offer largely unexplored potential...

Agricultural intensification has increased crop productivity but decreased agroecosystem services. Agricultural intensification is occurring notably for horticultural crops such as lettuce. In conventional agriculture, lettuce protection is achieved mostly by preventive applications of pesticides with about eight treatments for a 60–90-day-long cyc...

Vegetable production makes an intensive use of pesticides, and a major challenge is to build alternative cropping systems that can control pests and diseases with fewer uses of chemical products. An on-farm analysis was conducted in Southeast France to assess the efficacy of several cropping systems in simultaneously controlling two major pests: ro...

The aim of this work was to perform a sensitivity analysis of a modified biological simulator (TOMGRO) in tomato crop during winter period. The modified biological simulator (TOMGRO) that used for case studies of the experiment has been developed and validated according short cropping period, cultivation techniques and climate conditions of countri...

A combined greenhouse climate and crop model is crucial to predict the effect of global climate change on greenhouse production. Studying the consequences of climate change on crop production needs associating several sub-models dealing with: (i) greenhouse actuators control, (ii) greenhouse climate and (iii) tomato plant growth models. We have use...

Root-knot nematodes are a growing concern for vegetable producers, because chemical nematicides are gradually disappearing. Alternative techniques based on agronomic practices are needed to solve the problem. This review analyzes the most recent studies related to these techniques and their combinations and identifies the most effective ones. Based...

Grafting is an easier and faster approach than plant breeding to take advantage of both existing resistant plants, especially wild cultivars, and high-bred cultivars. The aim of this study was to investigate the changes in leaf photosynthetic capacity of a hybrid eggplant Solanum melongena L., cv. Rima (R), widely used in Greece] when grafted on to...

Agriculture is facing up to an increasing number of challenges, including the need to ensure various ecosystem services and to resolve apparent conflicts between them. One of the ways forward for agriculture currently being debated is a set of principles grouped together under the umbrella term “ecological intensification”. In published studies, ec...

The aim of this work was the development and validation of a biophysical model (BioSiGreT) by coupling a crop growth model and a greenhouse climate model. The crop growth model is a modification of TOMGRO to simulate topping, a short term cropping technique, current practice in Mediterranean greenhouses. The climate model consists of five sub-simul...

Cropping systems in in-soil protected cultivation are often very intensive and are characterized by a very low number of crops in the rotation. They are therefore very fragile with respect to soil-borne pests and diseases, and depend on pesticides. These cropping systems must be redesigned to exploit pesticide free techniques to control these soil-...

Les systèmes horticoles (arboriculture et maraîchage) sont parmi les plus intensifs en main d'oeuvre et en intrants ; la production conventionnelle repose sur un usage intense des produits phytosanitaires, pour satisfaire les critères d'accès aux circuits commerciaux des grandes et moyennes surfaces, et en particulier le "zéro défaut visuel".

Voir Article paru dans Innovations Agronomiques 9, 67-84

Market-gardening cropping systems in protected cultivation are very sensitive to soil-borne pests and diseases. Their productivity used to rely on pesticides, but alternative systems have now to be found for environmental, societal and health reasons. Many cultural techniques are known to provide some control of soilborne diseases, but are only par...

Market-gardening cropping systems in protected cultivation are very sensitive to soil-borne pests and diseases. Their productivity used to rely on pesticides, but alternative systems have now to be found for environmental, societal and health reasons. Many cultural techniques are known to provide some control of soilborne diseases, but are only par...

Cet article aborde les relations entre systèmes de culture sous abri et quelques aspects de la qualité des salades (qualité sanitaire liée à l’usage de produits phytosanitaires et aux résidus azotés). Il présente d’abord l’influence de quelques techniques et combinaisons de techniques alternatives, en se centrant sur le contrôle des maladies et en...

The aim of this work is to calibrate and validate the adaptation of TOMGRO (TOMato GRowth), a crop growth simulation model for tomato, to the short-term cropping technique and to conditions in Greece. Current practice in plastic greenhouses in Mediterranean regions is to stop the indeterminate development of the plant after a limited number of trus...