center for synthesis
and analysis of biodiversity

A centre created and developed by the FRB

Netseed Plus


NETSEED - Seed exchange networks
for agrobiodiversity conservation

The NETSEED research project (2011-2013) is funded by
the French Foundation for Research on Biodiversity (FRB)
through its Centre for Synthesis and Analysis of Biodiversity (CESAB)





  Group picture of the NETSEED meeting participants (October 2012). From left to right: Francois Massol, Oliver Coomes, Pascal Clouvel, Marco Pautasso, Guntra Aistara, Mathieu Thomas, Shawn McGuire, Sophie Caillon, Adeline Barnaud, Jean Wencelius, Chloe' Violon, Eric Garine, Doyle McKey, Selim Louafi & Pierre Martin


Contact: d_mckey(at) and sophie.caillon(at)

Please scroll down for:

1) a list of NETSEED project participants,

2) short summaries of the NETSEED project in English, Spanish, French and German,

2) a description of the two NETSEED-related sessions at the 13th Congress of the International Society for Ethnobiology (held in Montpellier, May 2012),

and 3) abstracts of literature on seed exchange networks by NETSEED participants.


NETSEED Project Participants, as of December 2012



Department of Environmental
Sciences and Policy
Central European University,
Budapest, Hungary

Adeline Barnaud

Plant Biodiversity
and Adaptation Research Group
French Institute for Research and Development (IRD), Montpellier, France

Sophie Caillon

  Centre for Functional
and Evolutionary Ecology
French National Centre for Scientific Research (CNRS), Montpellier, France

Pascal Clouvel

French Agricultural Research Centre for International Development (CIRAD), Montpellier, France

Kevin Coffey

International Research Center
for Climate & Society
Columbia University,
New York, USA


Oliver Coomes

Department of Geography,
McGill University,
Montreal, Canada

Marc Deletre

  Ecoanthropology & Ethniobiology Group, National Museum of
Natural History (MNHN),
Paris, France

Elise Demeulenaere

& Ethniobiology Group
National Museum of
Natural History (MNHN),
Paris, France

Ludivine Eloy

UMR 5281 "ART-Dev",
 University of Montpellier 3, France



Laure Emperaire

  IRD, Paris, France

 Eric Garine

Ethnobiology Group,
University of Paris 10
Nanterre, France

Isabelle Goldringer

Plant Genetics Research Group(Moulon), French National Institute for Agriculture (INRA), Versailles-Grignon, France
   Devra Jarvis


 Bioversity International,
Rome, Italy


   Francisco Laso


 University Montpellier 2,



Christian Leclerc

CIRAD, Montpellier, France

 Sélim Louafi

  CIRAD, Montpellier, France

Pierre Martin

CIRAD, Montpellier, France

François Massol

Montpellier, France

 Shawn McGuire

International Development,
University of East Anglia,
Norwich, UK

Doyle McKey

& University
of Montpellier 2

Christine Padoch

New York Botanical Garden,

Marco Pautasso


CEFE, CNRS (postdoc CESAB)
Montpellier, France


Benjavan Rerkasem


 Chiang Mai University, Thailand



Mathieu Thomas

 University of Groningen,
the Netherlands


Chloé Violon

 Ethnobiology Group,
University of Paris 10
Nanterre, France


Jean Wencelius

 Ethnobiology Group,
University of Paris 10
Nanterre, France


NETSEED project summary in English:

NETSEED: Seed exchange networks for agrobiodiversity conservation

Plant biodiversity within agricultural ecosystems is central for food security, dietary diversity, and sustainable farming. A key question is how the diversity of seeds can be maintained. As human activities have fragmented natural habitats, altered agricultural environments, and facilitated global-scale connections, understanding the diffusion of seed genetic resources has become particularly important.

The NETSEED research project aims to help farmers in the maintenance of seed flow networks, and thus enable human communities to adapt to the changing cultural, economic and environmental conditions.

More information can be found on the CESAB website:



Sinopsis del projecto NETSEED en espanol:

NETSEED: redes de circulation de semillas para la conservacion de la biodiversidad agricola

La biodiversidad vegetal en los ecosistemas agrícolas es fundamental para la seguridad, la diversidad alimentaria y la agricultura sostenible. Una cuestión clave es cómo puede mantenerse la diversidad de semillas. Dado que las actividades humanas han fragmentado los hábitats naturales, alterado ambientes agrícolas y facilitado conexiones a escala mundial, comprender la difusión de los recursos genéticos de las semillas se ha vuelto particularmente importante.

El proyecto de investigación NETSEED tiene como objetivo ayudar a los agricultores en el mantenimiento de redes de circulation de semillas, y así permitir a las comunidades humanas adaptarse a las cambiantes condiciones culturales, económicas y ambientales.

Se puede encontrar más información en el sitio web CESAB:



Resumé du projet NETSEED en francais:

NETSEED: Reseaux d'échange des semences pour la conservation de l'agrobiodiversité

La biodiversité des plantes cultivées est fondamentale pour la sécurité alimentaire des populations humaines, la diversification des nourritures et l’agriculture durable. Une question centrale est comment la diversité des semences peut etre preservée. Vu que les activités humaines ont fragmenté les habitats naturels, changé les environnements agricoles, et facilité des connections globales, c'est particulierement important de comprendre la diffusion des ressources genetiques des semences.

Le projet de recherche NETSEED a pour but de aider les agriculteurs à gerer les reseaux de diffusion des semences, et pourra ainsi aider le monde agricole à s’adapter aux changements environnementaux, culturels et économiques.

Vous pouvez trouver plus d'information sur le site web du CESAB:




Zusammenfassung vom NETSEED-Forschungsprojekt auf Deutsch:

NETSEED: Saatgutsaustauschnetzwerke fuer den Schutz der Agrobiodiversitaet

in landwirtschaftlichen Ökosystemen ist von zentraler Bedeutung für die Ernährungssicherheit, Nahrungsvielfalt und nachhaltige Landwirtschaft. Eine zentrale Frage ist, wie die Vielfalt von Saatgut aufrechterhalten werden kann. Da menschliche Aktivitäten natürliche Lebensräume fragmentieren, die landwirtschaftliche Umwelt
verändern und globale Verbindungen ermöglichen, ist das Verständnis der Diffusion von genetischer Saatgutsressourcen besonders wichtig geworden.

Das NETSEED-Forschungsprojekt zielt auf die Unterstützung der Landwirte in der Wartung von Saatgutsaustauschnetzwerke. Wir werden damit helfen, menschliche Gemeinschaften sich auf die sich ändernden kulturellen, wirtschaftlichen und ökologischen Bedingungen anzupassen.

Mehr Information kann auf der CESAB-Webseite gefunden werden:


Two NETSEED-related sessions at the 13th Congress of the ISE (Montpellier, May 2012)

We organized two NETSEED-related sessions at the 13th Congress of the International Society for Ethnobotany, Montpellier, May 2012


Session 10


Conservation through diffusion: Toward innovative models at the interface of formal and informal seed systems. May 24, 2012 (afternoon)

Co-chairs: G. Aistara & S. Caillon

In situ and ex situ approaches to the conservation of agricultural biodiversity offer complementary advantages and limitations. Consensus on this affirmation has guided research and application in breeding programs for over twenty years. Yet understanding the nature of agrobiodiversity, which includes dynamic processes and hybrid objects resulting from integration of traditional and scientific practices, may also require looking at familiar categories from an unfamiliar perspective. In this panel we will both evaluate concrete results and lessons learned from attempts to integrate in-situ and ex-situ systems, as well as explore innovations that push back frontiers. These may be new institutional arrangements that break down previously watertight categories, redefining domains without artificial boundaries. Questions include: How close are we to erasing the practical and legal dichotomies between formal and informal seed systems? What opportunities and pitfalls accompany the integration of formal and informal, ex situ and in situ? How do informal systems facilitate increased resilience that helps farmers respond to natural or manmade catastrophes? How do services of formal systems alter farmers’ capacity to adapt to dynamic and changing social, biological and physical environments? What role do landraces, whose evolution is dynamically managed by farmers, retain in this changing world? How might innovative farmer breeding techniques, such as the incorporation of “improved” material into landraces, influence future breeding models aimed at resilience and adaptation?

Oral presentations:

1. Introduction: “Conservation through diffusion” (Guntra Aistara, Central European University, Budapest, Hungary ; Sophie Caillon, CNRS, Montpellier)

2. Crop Community Genebanks: the missing link between ex situ and in situ conservation? The case of wheat and maize in France (Elise Demeulenaere, CNRS, Paris)

3. Gathering tradition, sowing the future! Some examples linking formal and informal seed systems from the North of Portugal (Ana Maria Barata, Filomena Rocha, Violeta Lopes, Banco Português de Germoplasma Vegetal/Instituto Nacional de Recursos Biológicos, Portugal; Jorge Miranda, Associação Regional de Desenvolvimento do Alto Lima, Portugal;  Margarida Telo Ramos, Ecomuseu Terra Mater, Portugal; Ana Maria Carvalho,Centro de Investigação de Montanha, Portugal)

4. Assessing farmers’ traditional vegetable seeds adoption and dissemination behavior in Kitui, Kenya (Toru Seki, Bioversity International, Nairobi, Kenya and Graduate School of International Development, Nagoya University, Nagoya, Japan; Yasuyuki Morimoto, Bioversity International, Nairobi, Kenya; Patrick Maundu, Bioversity International, Nairobi, Kenya and Graduate School of International Development, Nagoya University, Nagoya, Japan; Dominic Tumbo, Bioversity International, Nairobi, Kenya; Tomoya Matsumoto, National Graduate Institute for Policy Studies (GRIPS), Tokyo, Japan, and International Livestock Research Institute (ILRI), Nairobi, Kenya; Yoshiaki Nishikawa, Graduate School of International Development, Nagoya University, Nagoya, Japan; Pablo Eyzaguirre, Bioversity International, Nairobi, Kenya)

5. Understanding Crop Evolution: Unconscious Selection and the Diversification of Crop Species (Stephen Brush, University of California, Davis, USA)

6. Seed laws and their impact on agrobiodiversity in Brazil (Juliana Santilli, Ministério Público do Distrito Federal, Brazil)

7. Trans-situ memory and biodiversity conservation: Towards an out-of-place sense of place (Virginia D. Nazarea, University of Georgia, USA)





Session 28


Social networks of seed exchange and agrobiodiversity. An interdisciplinary method for analyzing how local seed systems impact the diversity of domesticated plants. May 24, 2012 (morning)

Co-chairs: D. McKey & M. Pautasso

Summary: The conservation of diversity, whether of wild or domesticated organisms, is a central issue in ethnobiology. Maintaining and managing agrobiodiversity is the key to achieving food security and well-being while using ecosystems sustainably. Effects of ‘seed’ flows can vary, from weakening locally adapted systems by introducing inappropriate material to strengthening these systems by increasing adaptability to global change or satisfying gastronomic curiosity. We will study seed exchange networks (SEENs) among farmers to assess how their structure – the signification, direction and intensity of seed fluxes among individuals or groups, and the distribution of genealogical, sociocultural or geographical distance among these individuals or social entities – impacts agrobiodiversity. Among these potential impacts, we are particularly interested in exploring:
(i)    the link between SEEN structure and the resiliency (i.e. speed of recovery after major modification) of agrobiodiversity;
(ii)    which SEEN structures favor the rapid dissemination of new varieties and associated knowledge or practices;
(iii)    sociocultural determinants of SEEN structure;
(iv)    which factors create different SEENs among plants grown by the same group of farmers (e.g. biological properties, end use, novelty, cultural values, social organization…);
(v)    how SEEN structure interacts with socio-economic factors (e.g. market integration, distribution of cultivars by national or international agricultural research centers, collective action institutions, geographical distance from original seed sources); (vi)    how SEEN structure explains current agrobiodiversity (not only in terms of named diversity, but also of genetic diversity, when data are available) and how a given SEEN can be modified to improve the social and ecological adaptability of local seed systems.

SEEN analysis lies at the intersection of natural and social sciences. As such, it is a hotspot for the development of new methods and concepts. Meta-analyses will combine datasets on exchanged seeds and on the social relationships between giver and recipient. We will compare visual representations of social network analysis softwares such as NetDraw (Borgatti 2003), NetVis (Cummings 2003), and Pajek (Batagelj and Mrvar 2003) with a model based on a semantic graph approach (Martin 2010). The goal is to give “sense” to our data among the heterogeneity of factors in order to predict certain aspects of SEEN functioning.

Oral presentations:

1. Genetic resources sourcing strategies and behavior of scientists: results from an international survey on researchers' use and exchange practices (Eric W. Welch & Selim Louafi) (cancelled due to a family emergency)

2. Farmers' social identity and crop genetic diversity. The G x E x S model (Christian Leclerc, Geo Coppens d'Eeckenbrugge)

3. What role do seed exchange networks play in recovering from a disaster? Evidence from seed
system security assessments (Shawn McGuire)

4. Sorghum, social links and genetic diversity in northern Cameroon (Adeline Barnaud, Hélène Joly, Monique Deu, Doyle McKey, Christine Raimond, Eric Garine)

5. How many seed systems are there in a Tupuri peasant community (Far-­‐North Region, Cameroon)? (Chloé Violon, Eric Garine, Olivier Kyburz)

6. Seed circulation networks in agrobiodiversity conservation: concepts, methods and challenges (Marco Pautasso)

7. Intercultural approach of sorghum folk taxonomy: how social network shapes knowledge exchanges in the Tharaka society (Kenya) (Vanesse Labeyrie, Christian Leclerc)

8. “The seeds of our fathers”: reproducing seeds across generations in Massa Society (Jean Wencelius, Eric Garine)

9. Context and semantics in exchange networks (Pierre Martin, Pascal Clouvel)






Literature on seed exchange networks from NETSEED project participants

(work on some of these papers had already been started
before the NETSEED project officially started)

Aistara G (2012) Privately public seeds: competing visions of property, personhood, and democracy in Costa Rica's entry into CAFTA and the Union for Plant Variety Protection (UPOV). Journal of Political Ecology 19: 127-144


Delêtre M, McKey DB & Hodkinson TR (2011) Marriage exchanges, seed exchanges and the dynamics of crop diversity. Proceedings of the National Academy of Sciences USA 108: 18249–18254

Abstract: The conservation of crop genetic resources requires understanding the different variables—cultural, social, and economic—that impinge on crop diversity. In small-scale farming systems, seed exchanges represent a key mechanism in the dynamics of crop genetic diversity, and analyzing the rules that structure social networks of seed exchange between farmer communities can help decipher patterns of crop genetic diversity. Using a combination of ethnobotanical and molecular genetic approaches, we investigated the relationships between regional patterns of manioc genetic diversity in Gabon and local networks of seed exchange. Spatially explicit Bayesian clustering methods showed that geographical discontinuities of manioc genetic diversity mirror major ethnolinguistic boundaries, with a southern matrilineal domain characterized by high levels of varietal diversity and a northern patrilineal domain characterized by low varietal diversity. Borrowing concepts from anthropology—kinship, bridewealth, and filiation—we analyzed the relationships between marriage exchanges and seed exchange networks in patrilineal and matrilineal societies. We demonstrate that, by defining marriage prohibitions, kinship systems structure social networks of exchange between farmer communities and influence the movement of seeds in metapopulations, shaping crop diversity at local and regional levels.

 Keywords: seed transmission - social reproduction - traditional economic systems

Döring TF, Pautasso M, Wolfe MS & Finckh MR (2012) Pest and disease management in organic farming: implications and inspirations for plant breeding. In: Lammerts Van Bueren ET & Myers JR (eds) Organic Crop Breeding. Wiley, pp. 39-60

Extract from the conclusions: From our review of plant breeding in the context of organic pest and disease management, four main messages emerge. The first is the tremendous importance of plant diversity for developing resilient agricultural production systems. [...] The second message is the importance of the economic dimension for plant breeding in plant protection contexts. [...] Third, plant protection in organic systems poses different challenges to plant breeding than does conventional agriculture. [...] Finally, breeding for plant protection needs to consider the dynamic and unpredictable nature of our constantly evolving agricultural systems.

Keywords: organic farming, pests and diseases, plant breeding, plant health, plant protection



Thomas F. Döring, Riccardo Bocci, Roger Hitchings, Sally Howlett, Edith T. Lammerts van Bueren,
Marco Pautasso, Maaike Raaijmakers, Frederic Rey, Anke Stubsgaard, Manfred Weinhappel, Klaus P. Wilbois, Louisa R. Winkler & Martin S. Wolfe (2012) The organic seed regulations framework in Europe — current status and recommendations for future development. Organic Agriculture, in press


Abstract: Organic agriculture regulations, in particular European regulation EC 889/2008, prescribe the use of organically produced seed. For many cultivated plants, however, organic seed is often not available. This is mainly because investment in organic plant breeding and seed production has been low in the past. To bridge the gap between organic seed supply and demand, national and European regulations define certain circumstances under which organic producers are permitted to use non-organically produced seed. While the organic sector currently depends on these concessions, they also threaten to impede a further increase in the demand for organic seed, thereby potentially restraining present and future investment in organic seed production and plant breeding. We review the current status of the organic seed regulations framework by analysing key issues such as the role of the national derogation regimes, the role of Expert Groups, databases and seed prices. Key points are that (a) the situation of the organic seed sector has improved over the last few years; however, (b) reporting on organic seed to the EU by different countries needs to be harmonised; (c) the success of the organic seed sector depends critically on the implementation and improvement of national Expert Groups; and (d) to protect genetic diversity, the use of local varieties and landraces should not be impeded by organic seed regulations.


Keywords: conservation varieties – Europe – organic – policy – regulation – seed


Leclerc C & Coppens d’ Eeckenbrugge G (2012) Social organization of crop genetic diversity. The G × E × S interaction model. Diversity 4: 1–32

Abstract: A better knowledge of factors organizing crop genetic diversity in situ increases the efficiency of diversity analyses and conservation strategies, and requires collaboration between social and biological disciplines. Four areas of anthropology may contribute to our understanding of the impact of social factors on crop diversity: ethnobotany, cultural, cognitive and social anthropology. So far, most collaborative studies have been based on ethnobotanical methods, focusing on farmers’ individual motivations and actions, and overlooking the effects of farmer’s social organization per se. After reviewing common shortcomings in studies on sorghum and maize, this article analyzes how social anthropology, through the analysis of intermarriage, residence and seed inheritance practices, can contribute to studies on crop genetic diversity in situ. Crop varieties are thus considered social objects and socially based sampling strategies can be developed. Such an approach is justified because seed exchange is built upon trust and as such seed systems are embedded in a pre-existing social structure and centripetally oriented as a function of farmers’ social identity. The strong analogy between farmers’ cultural differentiation and crop genetic differentiation, both submitted to the same vertical transmission processes, allows proposing a common methodological framework for social anthropology and crop population genetics, where the classical interaction between genetic and environmental factors, G × E, is replaced by a three-way interaction G × E × S, where “S” stands for the social differentiation factors.

Keywords: crop genetic resources - cultural transmission - in situ conservation - interdisciplinary approach - maize - seed exchange - social differentiation - social network - sorghum

Moslonka-Lefebvre M, Harwood T, Jeger MJ & Pautasso M (2012) SIS along a continuum epidemiological modelling and control of diseases on directed trade networks. Mathematical Biosciences 236: 44-52

Abstract: network theory has been applied to many aspects of biosciences, including epidemiology. Most epidemiological models in networks, however, have used the standard assumption of either susceptible or infected individuals. In some cases (e.g. the spread of Phytophthora ramorum in plant trade networks), a continuum in the infection status of nodes can better capture the reality of epidemics in networks. In this paper, a Susceptible-Infected-Susceptible model along a continuum in the infection status (SIS(c)) is presented, using as a case study directed networks and two parameters governing the epidemic process (probability of infection persistence (p(p)) and of infection transmission (p(t)). The previously empirically reported linear epidemic threshold in a plot of p(p) as a function of p(t) (Pautasso and Jeger, 2008) is derived analytically. Also the previously observed negative correlation between the epidemic threshold and the correlation between links in and out of nodes (Moslonka-Lefebvre et al., 2009) is justified analytically. A simple algorithm to calculate the threshold conditions is introduced. Additionally, a control strategy based on targeting market hierarchical categories such as producers, wholesalers and retailers is presented and applied to a realistic reconstruction of the UK horticultural trade network. Finally, various applications (e.g., seed exchange networks, food trade, spread of ideas) and potential refinements of the SIS(c) model are discussed.

Keywords: directed trade networks - epidemiology - hierarchical categories -
leading eigenvalue - metapopulation - SIS

Pautasso M, Aistara G, Barnaud A, Caillon S, Clouvel P, Coomes OT, Delêtre M, Demeulenaere E, De Santis P, Döring T, Eloy L, Emperaire L, Garine E, Goldringer I, Jarvis D, Joly HI, Leclerc C, Louafi S, Martin P, Massol F, McGuire S, McKey D, Padoch C, Soler C, Thomas M & Tramontini S (2013) Seed exchange networks for agrobiodiversity conservation. A review. Agronomy for Sustainable Development, in press


Abstract: The circulation of seed among farmers is central to agrobiodiversity conservation and dynamics. Agrobiodiversity, the diversity of agricultural systems from genes to varieties and crop species, from farming methods to landscape composition, is part of humanity’s cultural heritage. Whereas agrobiodiversity conservation has received much attention from researchers and policy makers over the last decades, the methods available to study the role of seed exchange networks in preserving crop biodiversity have only recently begun to be considered. In this overview, we present key concepts, methods, and challenges to better understand seed exchange networks so as to improve the chances that traditional crop varieties (landraces) will be preserved and used sustainably around the world. The available literature suggests that there is insufficient knowledge about the social, cultural, and methodological dimensions of environmental change, including how seed exchange networks will cope with changes in climates, socio-economic factors, and family structures that have supported seed exchange systems to date. Methods available to study the role of seed exchange networks in the preservation and adaptation of crop specific and genetic diversity range from meta-analysis to modelling, from participatory approaches to the development of bio-indicators, from genetic to biogeographical studies, from anthropological and ethnographic research to the use of network theory. We advocate a diversity of approaches, so as to foster the creation of robust and policy-relevant knowledge. Open challenges in the study of the role of seed exchange networks in biodiversity conservation include the development of methods to (i) enhance farmers’ participation to decision-making in agro-ecosystems, (ii) integrate ex situ and in situ approaches, (iii) achieve interdisciplinary research collaboration between social and natural scientists, and (iv) use network analysis as a conceptual framework to bridge boundaries among researchers, farmers and policy makers, as well as other stakeholders.


Keywords:  biodiversity – complex networks – global change – landscape genetics – methods in ecology and evolution – participatory approaches – review – scenarios – seeds – simulation models 



Pautasso M (2012) Challenges in the conservation and sustainable use of genetic resources. Biology Letters 23: 321-323



Abstract: The meeting on ‘Genetic Resources in the Face of New Environmental, Economic and Social Challenges’ held in Montpellier (France) from 20–22 September 2011 brought together about 200 participants active in research and management of the genetic diversity of plant, animal, fungal and microbial species. Attendees had the rare opportunity to hear about agronomy, botany, microbiology, mycology, the social sciences and zoology in the same conference. The research teams presented the results of about 50 projects funded by the French Foundation for Research on Biodiversity to preserve genetic diversity carried out in Africa, Asia, Europe and the Americas. These projects aimed to better understand and manage genetic resources in a rapidly changing world (e.g. structural changes in the agricultural industry, the need for climate change mitigation and adaptation, the challenge of achieving food security despite the growing world population and changing dietary habits, the opportunities provided by the many new molecular biology tools, the problems caused by widespread scientific budget cuts). The meeting also hosted some roundtables open to all participants which provided a forum to establish a much needed dialogue between policy-makers, managers and researchers.

Keywords: crop biodiversity - genetic tools - in situ conservation - intra-specific diversity -   population fragmentation - seed exchange networks





Louise Sperling & Shawn McGuire (2012) Fatal gaps in seed security strategy.
Food Security, in press


Abstract: Seed security initiatives are proliferating in both developmental and crisis contexts but the field as a whole is weak in critical thinking. Two gaps in particular are explored in this paper: the need to set explicit seed security goals and the need to ensure balance among the security elements of availability, access and quality. Differences in the planning and implementing of seed security initiatives are examined in some detail for programs that variously aim for: food production, nutritional enhancement, system resilience, and income generation. Results show that one seed security program is not like another and that features such as partner choice, product design, delivery and awareness-raising strategy need to be tailored to meet the overarching goals. The paper closes with five key policy and programming recommendations.

Keywords: climate change - food security – nutrition - resilience - seed security 







Thomas M, Demeulenaere E, Bonneuil C & Goldringer I (2012) On-farm conservation in industrialized countries: a way to promote dynamic management of biodiversity within agroecosystems. In: Maxted N, Dulloo ME, Ford-Lloyd BV, Frese L, Iriondo J, de Carvalho MAA Pinheiro (eds) Agrobiodiversity conservation: securing the diversity of crop wild relatives and landraces. CABI, Wallingford, pp 173–180




Abstract: In this chapter, we analyzed the role of social network as an actor in the sustainable management of crop genetic diversity, and we examined how this system is taken into account in the framework of the French policy for genetic resources. A brief description of folk varieties maintained in this social network is provided, results obtained on the folk variety named 'Rouge de Bordeaux' showing the link between genetic diversity and population structure and the social knowledge on farmers' practices and seed exchanges are summarized; and the stand taken by France on on-farm conservation (acknowledgement and policy) and the consequences for the sustainability of this conservation strategy are discussed.









Thomas M, Demeulenaere E, Dawson JC, Khan AR, Galic N, Jouanne-Pin S, Remoue C, Bonneuil C & Goldringer I (2012) On-farm dynamic management of genetic diversity: the impact of seed diffusions and seed saving practices on a population-variety of bread wheat. Evolutionary Applications, in press

Abstract: Since the domestication of crop species, humans have derived specific varieties for particular uses and shaped the genetic diversity of these varieties. Here, using an interdisciplinary approach combining ethnobotany and population genetics, we document the within-variety genetic structure of a population-variety of bread wheat (Triticum aestivum L.) in relation to farmers’ practices to decipher their contribution to crop species evolution. Using 19 microsatellites markers, we conducted two complementary graph theory-based methods to analyze population structure and gene flow among 19 sub-populations of a single population-variety [Rouge de Bordeaux (RDB)]. The ethnobotany approach allowed us to determine the RDB history including diffusion and reproduction events. We found that the complex genetic structure among the RDB sub-populations is highly consistent with the structure of the seed diffusion and reproduction network drawn based on the ethnobotanical study. This structure highlighted the key role of the farmer-led seed diffusion through founder effects, selection and genetic drift because of human practices. An important result is that the genetic diversity conserved on farm is complementary to that found in the genebank indicating that both systems are required for a more efficient crop diversity conservation.

Keywords: in situ conservation - interdisciplinary study - network theory - seed exchange network