Baobab (Adansonia digitata)

Conservation and sustainable use of genetic resources of priority food tree species in sub-Saharan AfricaConservation et utilisation durable des ressources génétiques des espèces ligneuses alimentaires prioritaires de l'Afrique subsaharienneLa publicación de esta hoja divulgativa ha sido financiada con la acción complementaria nº AC-2008-00050-00-00, titulada "Publicación de hojas divulgativas: Uso y gestión sostenible y conservación de especies forestales para la alimentación (ELA) en Africa Subsahariana" solicitada por el Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), investigador responsable: Eduardo Notivo

Geographic Variation in Specific Gravity Among Japanese Larch From Different Provenances

Genetic variation in wood specific gravity is reported for Japanese larch from twenty seed sources at age 17 years from planting in central New Brunswick, Canada. Information on native tamarack and European larch is also presented. Differences in mean specific gravity among provenances of Japanese larch (range 0.385 to 0.417) are highly significant. Specific gravity is not correlated with 12-year height, specific gravity of trees of the same provenances growing in Michigan, or with latitude, or elevation of the provenances. There is a weak but significant negative correlation between specific gravity and tree diameter at 1.3 m. Provenance x environment interaction in respect to specific gravity is high, making it difficult to identify provenances that will be superior over a wide area

Néré (Parkia biglobosa)

Conservation and sustainable use of genetic resources of priority food tree species in sub-Saharan AfricaConservation et utilisation durable des ressources génétiques des espèces ligneuses alimentaires prioritaires de l'Afrique subsaharienneLa publicación de esta hoja divulgativa ha sido financiada con la acción complementaria nº AC-2008-00050-00-00, titulada "Publicación de hojas divulgativas: Uso y gestión sostenible y conservación de especies forestales para la alimentación (ELA) en Africa Subsahariana" solicitada por el Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), investigador responsable: Eduardo Notivo

Conservation priorities for Prunus africana defined with the aid of spatial analysis of genetic data and climatic variables

Conservation priorities for Prunus africana, a tree species found across Afromontane regions, which is of great commercial interest internationally and of local value for rural communities, were defined with the aid of spatial analyses applied to a set of georeferenced molecular marker data (chloroplast and nuclear microsatellites) from 32 populations in 9 African countries. Two approaches for the selection of priority populations for conservation were used differing in the way they optimize representation of intra-specific diversity of P. africana across a minimum number of populations. The first method (Si) was aimed at maximizing genetic diversity of the conservation units and their distinctiveness with regard to climatic conditions, the second method (S2) at optimizing representativeness of the genetic diversity found throughout the species' range. Populations in East African countries (especially Kenya and Tanzania) were found to be of great conservation value, as suggested by previous findings. These populations are complemented by those in Madagascar and Cameroon. The combination of the two methods for prioritization led to the identification of a set of 6 priority populations. The potential distribution of P. africana was then modeled based on a dataset of 1,500 georeferenced observations. This enabled an assessment of whether the priority populations identified are exposed to threats from agricultural expansion and climate change, and whether they are located within the boundaries of protected areas. The range of the species has been affected by past climate change and the modeled distribution of P. africana indicates that the species is likely to be negatively affected in future, with an expected decrease in distribution by 2050. Based on these insights, further research at the regional and national scale is recommended, in order to strengthen P. africana conservation efforts

Present spatial diversity patterns of Theobroma cacao L. in the neotropics reflect genetic differentiation in Pleistocene refugia followed by human-influenced dispersal

Cacao (Theobroma cacao L.) is indigenous to the Amazon basin, but is generally believed to have been domesticated in Mesoamerica for the production of chocolate beverage. However, cacao's distribution of genetic diversity in South America is also likely to reflect pre-Columbian human influences that were superimposed on natural processes of genetic differentiation. Here we present the results of a spatial analysis of the intra-specific diversity of cacao in Latin America, drawing on a dataset of 939 cacao trees genotypically characterized by means of 96 SSR markers. To assess continental diversity patterns we performed grid-based calculations of allelic richness, Shannon diversity and Nei gene diversity, and distinguished different spatially coherent genetic groups by means of cluster analysis. The highest levels of genetic diversity were observed in the Upper Amazon areas from southern Peru to the Ecuadorian Amazon and the border areas between Colombia, Peru and Brazil. On the assumption that the last glaciation (22,000-13,000 BP) had the greatest pre-human impact on the current distribution and diversity of cacao, we modeled the species' Pleistocene niche suitability and overlaid this with present-day diversity maps. The results suggest that cacao was already widely distributed in the Western Amazon before the onset of glaciation. During glaciations, cacao populations were likely to have been restricted to several refugia where they probably underwent genetic differentiation, resulting in a number of genetic clusters which are representative for, or closest related to, the original wild cacao populations. The analyses also suggested that genetic differentiation and geographical distribution of a number of other clusters seem to have been significantly affected by processes of human management and accompanying genetic bottlenecks. We discuss the implications of these results for future germplasm collection and in situ, on farm and ex situ conservation of cacao

Genetic considerations in ecosystem restoration using native tree species

Rehabilitation and restoration of forest ecosystems are in growing demand to tackle climate change, biodiversity loss and desertification—major environmental problems of our time. Interest in restoration of ecosystems is increasingly translated into strong political commitment to large-scale tree planting projects. Along with this new impetus and the enormous scale of planned projects come both opportunities and risks: opportunities to significantly increase the use of native species, and risks of failure associated with the use of inadequate or mismatched reproductive material, which though it may provide forest cover in the short term, will not likely establish a self-sustaining ecosystem. The value of using native tree species in ecosystem restoration is receiving growing recognition both among restoration practitioners and policy makers. However, insufficient attention has been given to genetic variation within and among native tree species, their life histories and the consequences of their interactions with each other and with their environment. Also restoration practitioners have often neglected to build in safeguards against the anticipated effects of anthropogenic climate change. Measurement of restoration success has tended to be assessments of hectares covered or seedling survival in a short timeframe, neither of which is an indicator of ecosystem establishment in the long term. In this article, we review current practices in ecosystem restoration using native tree species, with a particular focus on genetic considerations. Our discussion is organised across three themes: (i) species selection and the sourcing of forest reproductive material; (ii) increasing resilience by fostering natural selection, ecological connectivity and species associations; and (iii) measuring the success of restoration activities. We present a number of practical recommendations for researchers, policymakers and restoration practitioners to increase the potential for successful interventions. We recommend the development and adoption of decision-support tools for: (i) collecting and propagating germplasm in a way that ensures a broad genetic base of restored tree populations, including planning the sourcing of propagation material of desired species well before the intended planting time; (ii) matching species and provenances to restoration sites based on current and future site conditions, predicted or known patterns of variation in adaptive traits and availability of seed sources; and (iii) landscape-level planning in restoration projects

Is local best? Examining the evidence for local adaptation in trees and its scale

Background: Although the importance of using local provenance planting stock for woodland production, habitat conservation and restoration remains contentious, the concept is easy to understand, attractive and easy to ‘sell’. With limited information about the extent and scale of adaptive variation in native trees, discussion about suitable seed sources often emphasises “local” in a very narrow sense or within political boundaries, rather than being based on sound evidence of the scale over which adaptation occurs. Concerns exist over the actual scale (magnitude and spatial scale) of adaptation in trees and the relative dangers of incorrect seed source or restricted seed collection, leading to the establishment of trees with restricted genetic diversity and limited adaptive potential. Tree provenance and progeny field trials in many parts of the world have shown the existence of genotype by environment interaction in many tree species, but have not necessarily looked at whether this is expressed as a home site advantage (i.e. whether provenance performance is unstable across sites, and there is better performance of a local seed source). Methods/design: This review will examine the evidence for local adaptation and its scale in a number of native tree species from different trial sites across the globe (e.g. tropical, Mediterranean, temperate). These trials have been measured and in some cases results published in a range of formats. The data have, however, usually been presented in the form of which provenances grow best at which sites. The review will examine existing data (published and unpublished) in the context of the scale of local adaptation, with the results being presented in two formats: (a) relating survival, performance of provenances (classified by seed zone/provenance region of origin) to seed zone/provenance region of the planting site; (b) plotting survival, performance provenances against the distance (Euclidean/ecological) between the provenance and the trial site.EEA BarilocheFil: Boshier, David. University of Oxford. Department of Plant Sciences; Reino UnidoFil: Broadhurst, Linda. CSIRO National Research Collections Australia (NRCA). Centre for Australian National Biodiversity Research (CANBR); AustraliaFil: Cornelius, Jonathan. International Center for Research in Agroforestry. World Agroforestry Centre; PerúFil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Koskela, Jarkko. FAO; ItaliaFil: Loo, Judy. Bioversity International; ItaliaFil: Petrokofsky, Gillian. University of Oxford. Department of Zoology; Reino UnidosFil: St Clair, Bradley. US Forest Service. Pacific Northwest Research Station; Estados Unido

Is local best? Examining the evidence for local adaptation in trees and its scale

Background: Although the importance of using local provenance planting stock for woodland production, habitat conservation and restoration remains contentious, the concept is easy to understand, attractive and easy to ‘sell’. With limited information about the extent and scale of adaptive variation in native trees, discussion about suitable seed sources often emphasises “local” in a very narrow sense or within political boundaries, rather than being based on sound evidence of the scale over which adaptation occurs. Concerns exist over the actual scale (magnitude and spatial scale) of adaptation in trees and the relative dangers of incorrect seed source or restricted seed collection, leading to the establishment of trees with restricted genetic diversity and limited adaptive potential. Tree provenance and progeny field trials in many parts of the world have shown the existence of genotype by environment interaction in many tree species, but have not necessarily looked at whether this is expressed as a home site advantage (i.e. whether provenance performance is unstable across sites, and there is better performance of a local seed source). Methods/design: This review will examine the evidence for local adaptation and its scale in a number of native tree species from different trial sites across the globe (e.g. tropical, Mediterranean, temperate). These trials have been measured and in some cases results published in a range of formats. The data have, however, usually been presented in the form of which provenances grow best at which sites. The review will examine existing data (published and unpublished) in the context of the scale of local adaptation, with the results being presented in two formats: (a) relating survival, performance of provenances (classified by seed zone/provenance region of origin) to seed zone/provenance region of the planting site; (b) plotting survival, performance provenances against the distance (Euclidean/ecological) between the provenance and the trial site.EEA BarilocheFil: Boshier, David. University of Oxford. Department of Plant Sciences; Reino UnidoFil: Broadhurst, Linda. CSIRO National Research Collections Australia (NRCA). Centre for Australian National Biodiversity Research (CANBR); AustraliaFil: Cornelius, Jonathan. International Center for Research in Agroforestry. World Agroforestry Centre; PerúFil: Gallo, Leonardo Ariel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Koskela, Jarkko. FAO; ItaliaFil: Loo, Judy. Bioversity International; ItaliaFil: Petrokofsky, Gillian. University of Oxford. Department of Zoology; Reino UnidosFil: St Clair, Bradley. US Forest Service. Pacific Northwest Research Station; Estados Unido

Utilization and transfer of forest genetic resources: A global review

AbstractOver the last 200years, genetic resources of forest trees have been increasingly transferred, within and outside of species’ native distribution ranges, for forestry and for research and development (R&D). Transferred germplasm has been deployed to grow trees for numerous purposes, ranging from the production of wood and non-wood products to the provision of ecosystem services such as the restoration of forests for biodiversity conservation. The oldest form of R&D, provenance trials, revealed early on that seed origin has a major influence on the performance of planted trees. International provenance trials have been essential for selecting seed sources for reforestation and for improving tree germplasm through breeding. Many tree breeding programmes were initiated in the 1950s, but as one round of testing and selection typically takes decades, the most advanced of them are only in their third cycle. Recent advances in forest genomics have increased the understanding of the genetic basis of different traits, but it is unlikely that molecular marker-assisted approaches will quickly replace traditional tree breeding methods. Furthermore, provenance trials and progeny tests are still needed to complement new research approaches. Currently, seed of boreal and temperate trees for reforestation purposes are largely obtained from improved sources. The situation is similar for fast growing tropical and subtropical trees grown in plantations, but in the case of tropical hardwoods and many agroforestry trees, only limited tested or improved seed sources are available. Transfers of tree germplasm involve some risks of spreading pests and diseases, of introducing invasive tree species and of polluting the genetic make-up of already present tree populations. Many of these risks have been underestimated in the past, but they are now better understood and managed. Relatively few tree species used for forestry have become invasive, and the risk of spreading pests and diseases while transferring seed is considerably lower than when moving live plants. The implementation of the Nagoya Protocol on access to genetic resources and benefit sharing (ABS) may significantly change current transfer practices in the forestry sector by increasing transaction costs and the time needed to lawfully obtain forest genetic resources for R&D purposes. Many countries are likely to struggle to establish a well-functioning ABS regulatory system, slowing down the process of obtaining the necessary documentation for exchange. This is unfortunate, as climate change, outbreaks of pests and diseases, and continual pressure to support productivity, increase the need for transferring tree germplasm and accelerating R&D