Conservation Of Crop Genetic Resources Research Articles

High Public Good Values for Ecosystem Service Attributes of on-farm Quinoa Diversity Conservation in Peru

Agrobiodiversity is associated with a range of important but poorly quantified public good ecosystem services, the conservation of which requires public support. With a view to determining the general public’s willingness to pay (WTP) for such conservation, we organised interviews with 491 adult Peruvian residents in three regions a stated preference choice experiment (CE) to elicit the value they place on crop genetic resources conservation, using quinoa cultivation as a case study. Responses revealed strong support for the conservation of quinoa diversity particularly when conservation was framed in terms of conserving national cultural identity or food security. Respondents were willing to make a one-off donation of US$31.79 to an in situ on-farm quinoa crop diversity conservation programme, placing the highest values on programme attributes related to securing bequest/existence and option values, followed closely by stable landscape conservation. WTP was higher when the public was reminded that conservation also contributed to national cultural identify or food security. A conservative aggregation of the WTP estimates to the population of the three regions results in an estimated total WTP for quinoa conservation of US$24.18 m and a benefit-cost ratio of 1.22. Findings demonstrate the significant and frequently ignored social welfare benefits associated with non-market agrobiodiversity-related public good ecosystem services, in this case equivalent to just over a quarter of market production values. Such information can be used to design and prioritise quinoa genetic diversity conservation programmes with an emphasis on such attributes.

The history of seed banking and the hazards of backup.

Seeds and other plant materials in seed and gene bank collections are rarely considered adequately conserved today unless genetically identical duplicate samples have been created and safely stored elsewhere. This paper explores the history of seed banking to understand how, why and with what consequences copying collections came to occupy this central place. It highlights a shift in the guiding metaphor for long-term preservation of seed collections, from banking to backup. To understand the causes and consequences of this shift in metaphor, the paper traces the intertwined histories of the central long-term seed storage facility of the United States (opened in 1958) and the international seed conservation system into which that facility was integrated in the 1970s. This account reveals how changing conceptions of security, linked to changing economic, political and technological circumstances, transformed both the guiding metaphors and the practices of seed conservation in these institutions. Early instantiations of long-term cold storage facilities vested security in robust infrastructures and the capacities of professional staff; between the 1960s and 1990s, this configuration gave way to one in which security was situated in copies rather than capacities. This observation ultimately raises questions about the security promised and achieved through present-day infrastructures for crop genetic resources conservation.

Challenges and Prospects for the Conservation of Crop Genetic Resources in Field Genebanks, in In Vitro Collections and/or in Liquid Nitrogen.

The conservation of crop genetic resources, including their wild relatives, is of utmost importance for the future of mankind. Most crops produce orthodox seeds and can, therefore, be stored in seed genebanks. However, this is not an option for crops and species that produce recalcitrant (non-storable) seeds such as cacao, coffee and avocado, for crops that do not produce seeds at all; therefore, they are inevitably vegetatively propagated such as bananas, or crops that are predominantly clonally propagated as their seeds are not true to type, such as potato, cassava and many fruit trees. Field, in vitro and cryopreserved collections provide an alternative in such cases. In this paper, an overview is given on how to manage and setup a field, in vitro and cryopreserved collections, as well as advantages and associated problems taking into account the practical, financial and safety issues in the long-term. In addition, the need for identification of unique accessions and elimination of duplicates is discussed. The different conservation methods are illustrated with practical examples and experiences from national and international genebanks. Finally, the importance of establishing safe and long-term conservation methods and associated backup possibilities is highlighted in the frame of the global COVID-19 pandemic.

Institutions and Mechanism Linking Conservation of Crop Genetic Resources and Seed Sovereignty

Institutions and Mechanism Linking Conservation of Crop Genetic Resources and Seed Sovereignty

Conservation of crop genetic resources in Brazil in the context of the target 9 of the Global Strategy for Plant Conservation

Abstract Cultivated species, on which humankind depends for survival, have been created by farmers that have crossed and selected wild plants and developed landraces. Early in 20th century, the theory of Centers of Origin of Cultivated Plants was proposed by Vavilov. He also warned the world about the loss of plant genetic diversity due to the dominance of a small number of genetically similar crops, a fact that help starting a movement for the conservation of plant genetic resources. From this time, several strategies and institutions were established around the world to act in plant genetic resources (PGR) conservation. In Brazil, a remarkable player in PGR conservation, some institutions conserve several crop species as well as their wild relatives and other socio-economically valuable plant species. In this paper we present the status of PGR conservation in Brazil as well as initiatives and laws aiming at respecting, preserving and maintaining associated indigenous and local knowledge, in the context of the target 9 of the Global Strategy for Plant Conservation.

Conservation of Crop Genetic Resources in Italy with a Focus on Vegetables and a Case Study of a Neglected Race of Brassica Oleracea

This study attempts, above all, to provide a summary, on a strictly scientific basis, about the strategies of conservation of autochthonous agrobiodiversity followed in Italy. A special focus is dedicated to vegetables and, therefore, could represent a contribution to improve the national strategy for the safeguarding of its agrobiodiversity in general. The paper offers also an outlook on the most critical factors of ex situ conservation and actions which need to be taken. Some examples of ‘novel’ recovered neglected crops are also given. Finally a case study is proposed on ‘Mugnolicchio’, a neglected race of Brassica oleracea L., cultivated in Altamura (Ba) in southern Italy, that might be considered as an early step in the evolution of broccoli (B. oleracea L. var. italica Plenck) like ‘Mugnoli’ another neglected race described from Salento (Apulia).

Is It Still Necessary to Continue to Collect Crop Genetic Resources in the Mediterranean Area? A Case Study in Catalonia

Crop genetic resources have been extensively collected in Europe in the last century, creating large, publicly available ex situ collections. While this huge genetic diversity is often underutilized, in recent decades, several initiatives have emerged at the local level to collect germplasm cultivated on farm. Uncoordinated actors often carry out these collecting missions without considering previously collected data. To explore whether new collecting missions are likely to be worthwhile, we studied the crop genetic resources conservation network in Catalonia by analyzing the passport data and geographical distribution of germplasm stored in seed banks. Moreover, to determine whether this germplasm was representative of the diversity cultivated on farm, we performed new collecting missions in four randomly selected areas in the European Union’s Natura 2000 network and compared the results with the ex situ databases. Seed banks currently hold a large germplasm collection (2931 accessions), although most materials are conserved in private collections without regulated systems for seed regeneration and are not present as duplicates in the National Inventory. One important shortcoming of the ex situ network is that the germplasm conserved ex situ shows a low geographical coverage, representing only 35.3% of the municipalities in Catalonia. Our new missions allowed us to collect 234 accessions, mostly tomatoes (17.5%) and beans (16.2%). The ecological indicators’ richness (both at species (S) and variety (V) levels), total abundance (A), and the Shannon-Weaver diversity index calculated at species (H2, considering the different accessions of each variety as a single population) and variety levels (H3, considering the intra-varietal genetic diversity) were higher in the newly collected germplasm than in the ex situ collections, suggesting that seed banks do not accurately represent the genetic diversity still cultivated on farm. Moreover, some important landraces from each area were absent or underrepresented in the ex situ collections. Thus, it is necessary to continue to devote efforts to collecting germplasm; better organization between actors and targeting specific species/varieties can increase the efficiency of new collecting missions. As a conclusion, we propose different criteria to guide new missions and to improve the network’s conservation activities.

Old Crop, New Society: Persistence and Change of Tartary Buckwheat Farming in Yunnan, China

Traditional agricultural systems are important for crop genetic resources conservation. Many scholars have addressed the problem of traditional cultivar replacement by modern varieties, but few have investigated the entire loss of traditional crops from farming systems. Our prior research suggested that tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) agriculture is rapidly decreasing in Yunnan China, the center of the crop’s origin and an important repository of on-farm genetic diversity. Using interdisciplinary methodology to determine whether the crop is indeed in decline and evaluate reasons behind planting trends, we found a combination of interacting agroecological, socio-cultural, and institutional factors influence tartary buckwheat planting in Yunnan. Farmer ethnicity, presence of a commercial market for the crop, and government agricultural policy were particularly important. Low commercial value of the crop compared to other alternatives, reduction of available farmland, and labor shortages were major reasons cited for crop abandonment. Despite an overall reduction in tartary buckwheat planting across a wide spectrum of farms, we also found the crop retains subsistence, rotational and cultural value for many Yunnan farmers. We conclude that although Yunnan farms are increasingly managed commercially rather than for subsistence, tartary buckwheat will continue to occupy a niche in the agricultural landscape.

Unexpected pattern of pearl millet genetic diversity among ethno-linguistic groups in the Lake Chad Basin

Despite of a growing interest in considering the role of sociological factors in seed exchanges and their consequences on the evolutionary dynamics of agro-biodiversity, very few studies assessed the link between ethno-linguistic diversity and genetic diversity patterns in small-holder farming systems. This is key for optimal improvement and conservation of crop genetic resources. Here, we investigated genetic diversity at 17 SSR markers of pearl millet landraces (varieties named by farmers) in the Lake Chad Basin. 69 pearl millet populations, representing 27 landraces collected in eight ethno-linguistic farmer groups, were analyzed. We found that the farmers’ local taxonomy was not a good proxy for population’s genetic differentiation as previously shown at smaller scales. Our results show the existence of a genetic structure of pearl millet mainly associated with ethno-linguistic diversity in the western side of the lake Chad. It suggests there is a limit to gene flow between landraces grown by different ethno-linguistic groups. This result was rather unexpected, because of the highly outcrossing mating system of pearl millet, the high density of pearl millet fields all along the green belt of this Sahelian area and the fact that seed exchanges among ethno-linguistic groups are known to occur. In the eastern side of the Lake, the pattern of genetic diversity suggests a larger efficient circulation of pearl millet genes between ethno-linguistic groups that are less numerous, spatially intermixed and, for some of them, more prone to exogamy. Finally, other historical and environmental factors which may contribute to the observed diversity patterns are discussed.

Past and present dynamics of sorghum and pearl millet diversity in Mount Kenya region.

Crop populations in smallholder farming systems are shaped by the interaction of biological, ecological, and social processes, occurring on different spatiotemporal scales. Understanding these dynamics is fundamental for the conservation of crop genetic resources. In this study, we investigated the processes involved in sorghum and pearl millet diversity dynamics on Mount Kenya. Surveys were conducted in ten sites distributed along two elevation transects and occupied by six ethnolinguistic groups. Varieties of both species grown in each site were inventoried and characterized using SSR markers. Genetic diversity was analyzed using both individual‐ and population‐based approaches. Surveys of seed lot sources allowed characterizing seed‐mediated gene flow. Past sorghum diffusion dynamics were explored by comparing Mount Kenya sorghum diversity with that of the African continent. The absence of structure in pearl millet genetic diversity indicated common ancestry and/or important pollen‐ and seed‐mediated gene flow. On the contrary, sorghum varietal and genetic diversity showed geographic patterns, pointing to different ancestry of varieties, limited pollen‐mediated gene flow, and geographic patterns in seed‐mediated gene flow. Social and ecological processes involved in shaping seed‐mediated gene flow are further discussed.

Root crops diversity and agricultural resilience: a case study of traditional agrosystems in Vanuatu (Oceania)

In Vanuatu (Oceania), small-scale farmers’ subsistence still largely relies on the sustainable use and maintenance of a wide-ranging biodiversity out of which root and tuber crops provide the bulk of daily subsistence. In neighboring countries, foreign influence since the first European contacts, further associated changes and the introduction of new crop species have induced a loss of cultivated diversity. This paper presents a baseline study of the diversity of root and tuber crops in ten communities throughout Vanuatu. In a context where the smallholders’ agrosystems are increasingly considered as key components for the global conservation of crop genetic resources, this study provides clues to better understand the effective roles of biodiversity in traditional agrosystems. It also provides insights on the rationale behind the constitution of agricultural portfolios and discusses how the cultivated diversity allows communities to cope with changes and pressures. The paper also shows that recently introduced crops neither seem to have compromised agricultural diversity nor drastically changed the agrosystems in Vanuatu. On the contrary, such crops are used by farmers to strengthen the resilience of their agrosystems. A discussion then presents the idea of continuity through change and novelty as a critical factor for resilience. The paper concludes by discussing the role of indigenous agriculture and culture in ensuring food security and in development strategies in a larger context.

Assessing Genetic Diversity in Landraces of Cucurbita spp. Using a Morphological and Molecular Approaches

Agriculture can only be considered as sustainable if it includes a suitable system of plant genetic resources conservation. Crop genetic resources conservation is an insurance against risks to food security. The landraces stand important genetic resources for plant breeders due to its genotypic variability. In Portugal, the production of Cucurbita is based in old local cultivars and is mainly for self-consumption (human food or feed) and is sale on local markets. To evaluate the diversity of 54C. pepo, 32C. maxima and 21C. moschata populations collected in Northern and inner center of Portugal, 20 morphological traits from the Minimum Descriptors for Cucurbita spp. and six microsatellites were used. The traits that registered the highest mean values were the fruit length, the skin thickness and the seed weight, in C. pepo, the fruit width and 100 seed weight in C. maxima and the fruit weight and flesh thickness in C. moschata populations. The ANOVA revealed significant differences (P<0.05) for all traits, with exception of skin thickness parameter. The PCA showed that the three most informative PC explained 52.5% of the total variation and a clear separation of the three species. The molecular analysis with SSR markers revealed a polymorphism of 100%. The Ho and He average were 0.316 and 0.447, respectively. The PIC showed an average of 0.688. The hierarchical analysis revealed a clear separation of the three Curcubita species. The PCoA showed that the three most informative PC explained 66.3% of the total variation and clearly separated the three species studied. The high genetic diversity found in this Portuguese collection of Cucurbita spp. provides relevant information for the diversity conservation and can be useful for breeding programs.

Local–Global Linkages in Environmental Governance: The Case of Crop Genetic Resources

The loss of biodiversity is a global environmental problem that poses important governance challenges. Effective governance of crop genetic resources as a component of biodiversity is essential, given that such resources are the building blocks of today's modern agriculture. This article examines the formal governance framework in place for crop genetic resources, as embodied in the Convention on Biological Diversity and the International Treaty on Plant Genetic Resources for Food and Agriculture, and compares this to alternative modes of governance proposed by peasants' organizations such as Via Campesina. The author argues that the existing formal governance framework falls short of providing an effective mechanism for the conservation of crop genetic resources. Alternative governance mechanisms may more effectively connect the local and the global in a way that recognizes the contributions of local communities to conserving genetic resources in centers of diversity, and re-embeds their control over agricultural production processes.

Genetic Composition and Spatial Distribution of Farmer‐managed Phaseolus Bean Plantings: An Example from a Village in Oaxaca, Mexico

ABSTRACTIn situ conservation of crop genetic resources is an important complement to ex situ conservation, yet little is known about how small‐scale farmers perceive diversity in their own fields. In this study, we investigated the role of farmers from a community in the Sierra Juárez, Oaxaca, Mexico, in managing Phaseolus bean diversity in their fields. We collected seeds from 287 plants in 10 fields in the village of Santa María Jaltianguis and evaluated the diversity present in the collection at 10 nuclear and three chloroplast DNA (cpDNA) microsatellite markers. Following a Structure analysis, three core population clusters were identified in the collection, a finding corroborated by morphological observations, principal coordinate analysis, and neighbor‐joining tree construction using molecular data. The first two populations were identified as Phaseolus vulgaris L. ecogeographic races Mesoamerica and Jalisco and the third population as related species Phaseolus coccineus L. and Phaseolus dumosus Macfad. Each of the fields sampled consisted predominantly of a single Phaseolus species or ecogeographic race, but there was also evidence of low levels of gene flow between races Jalisco and Mesoamerica. Our data suggest farmers in Santa María Jaltianguis recognize existing inter‐ and intraspecies diversity in Phaseolus, its differential adaptation, its capacity to exploit a broad range of growing environments, and its potential to buffer the community against socioeconomic and climatic changes.

The original features of rice (Oryza sativa L.) genetic diversity and the importance of within-variety diversity in the highlands of Madagascar build a strong case for in situ conservation

In situ conservation of crop genetic resources is widely recommended but, as yet, no methods have been developed to rank the genetic entities to preserve and the social organisations to involve. The highlands of Madagascar have been identified as a key site for rice, Oryza sativa, genetic diversity. To define conservation strategies, we performed multidisciplinary analysis of rice genetic diversity and factors shaping its distribution in the target region. Along with the indica and japonica rice subspecies of O. sativa, we confirmed the presence of an atypical rice group with a preferential habitat of 1,250–1,750 m. Spatial distribution of genetic diversity was uneven. The most determining factor of this unevenness was the altitude authorising or not the presence of different rice cropping systems and the associated types of varieties. Village and individual farmer’s wealth also had a determining role on the amount of rice diversity they hosted. While molecular variance between villages in a given interval of altitude represented 16 % of the total variance, within-village variance represented more than 75 % of the total, and within-farm variance 70 % of within-village variance. This hierarchical distribution of molecular variance suggests that a small number of samples per scale (altitude interval, village and farm) could allow to capture most of the genetic diversity observed. However, within-variety diversity was also important making ex situ conservation strategies impractical and costly. Implications of the within-variety diversity are discussed in terms of adaptive advantages, evolutionary processes, and need for in situ conservation.

Marriage exchanges, seed exchanges, and the dynamics of manioc diversity

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.

Evolutionary response of landraces to climate change in centers of crop diversity.

Landraces cultivated in centers of crop diversity result from past and contemporary patterns of natural and farmer-mediated evolutionary forces. Successful in situ conservation of crop genetic resources depends on continuity of these evolutionary processes. Climate change is projected to affect agricultural production, yet analyses of impacts on in situ conservation of crop genetic diversity and farmers who conserve it have been absent. How will crop landraces respond to alterations in climate? We review the roles that phenotypic plasticity, evolution, and gene flow might play in sustaining production, although we might expect erosion of genetic diversity if landrace populations or entire races lose productivity. For example, highland maize landraces in southern Mexico do not express the plasticity necessary to sustain productivity under climate change, but may evolve in response to altered conditions. The outcome for any given crop in a given region will depend on the distribution of genetic variation that affects fitness and patterns of climate change. Understanding patterns of neutral and adaptive diversity from the population to the landscape scale is essential to clarify how landraces conserved in situ will continue to evolve and how to minimize genetic erosion of this essential natural resource.

Shifts in African crop climates by 2050, and the implications for crop improvement and genetic resources conservation

Increased understanding of the substantial threat climate change poses to agriculture has not been met with a similarly improved understanding of how best to respond. Here we examine likely shifts in crop climates in Sub-Saharan Africa under climate change to 2050, and explore the implications for agricultural adaptation, with particular focus on identifying priorities in crop breeding and the conservation of crop genetic resources. We find that for three of Africa's primary cereal crops – maize, millet, and sorghum – expected changes in growing season temperature are considerable and dwarf changes projected for precipitation, with the warmest recent temperatures on average cooler than almost 9 out of 10 expected observations by 2050. For the “novel” crop climates currently unrepresented in each country but likely extant there in 2050, we identify current analogs across the continent. The majority of African countries will have novel climates over at least half of their current crop area by 2050. Of these countries, 75% will have novel climates with analogs in the current climate of at least five other countries, suggesting that international movement of germplasm will be necessary for adaptation. A more troubling set of countries – largely the hotter Sahelian countries – will have climates with few analogs for any crop. Finally, we identify countries, such as Sudan, Cameroon, and Nigeria, whose current crop areas are analogs to many future climates but that are poorly represented in major genebanks – promising locations in which to focus future genetic resource conservation efforts.

Collection and characterization of maize and upland rice populations cropped by poor farmers in the uplands of Panama's Azuero region

The conservation of crop genetic resources is an international priority and requires the continued collection and characterization of farmer varieties. We collected and characterized maize and upland rice populations cropped by farmers in Panama's Azuero region. The objective of our study was to evaluate the crop genetic diversity of farmer varieties of maize and upland rice grown by poor farmers in Panama. We found that: (1) farmers' naming practices only partially corresponded to genetic relationships and were the strongest for rice populations; (2) farmers' classification of populations as ‘modern’ or ‘traditional’ was reflected in phenotypic differences; (3) Panamanian maize populations were molecularly distinct from populations collected elsewhere in Latin America; and (4) heterogeneous rice populations were common and heterogeneity was often due to admixture of recognized farmer varieties. Our results indicate that poor farmers in Panama continue to farm ‘traditional’ varieties that harbour genetic diversity of interest. There has, however, been substantial adoption of ‘modern’ varieties.

Asymmetrical local adaptation of maize landraces along an altitudinal gradient.

Crop landraces are managed populations that evolve in response to gene flow and selection. Cross-pollination among fields, seed sharing by farmers, and selection by management and environmental conditions play roles in shaping crop characteristics. We used common gardens to explore the local adaptation of maize (Zea mays ssp. mays) landrace populations from Chiapas, Mexico to altitude. We sowed seeds of 21 populations from three altitudinal ranges in two common gardens and measured two characteristics that estimate fitness: likelihood of producing good quality seed and the total mass of good quality seed per plant. The probability of lowland plants producing good quality seed was invariably high regardless of garden, while highland landraces were especially sensitive to altitude. Their likelihood of producing good seed quadrupled in the highland site. The mass of good quality seed showed a different pattern, with lowland landraces producing 25% less seed mass than the other types at high elevations. Combining these two measures of fitness revealed that the highland landraces were clearly adapted to highland sites, while lowland and midland landraces appear more adapted to the midland site. We discuss this asymmetry in local adaptation in light of climate change and in situ conservation of crop genetic resources.