Toward Unifying Global Hotspots of Wild and Domesticated Biodiversity

Abstract

Global biodiversity hotspots are areas containing high levels of species richness, endemism and threat. Similarly, regions of agriculturally relevant diversity have been identified where many domesticated plants and animals originated, and co-occurred with their wild ancestors and relatives. The agro-biodiversity in these regions has, likewise, often been considered threatened. Biodiversity and agro-biodiversity hotspots partly overlap, but their geographic intricacies have rarely been investigated together. Here we review the history of these two concepts and explore their geographic relationship by analysing global distribution and human use data for all plants, and for major crops and associated wild relatives. We highlight a geographic continuum between agro-biodiversity hotspots that contain high richness in species that are intensively used and well known by humanity (i.e., major crops and most viewed species on Wikipedia) and biodiversity hotspots encompassing species that are less heavily used and documented (i.e., crop wild relatives and species lacking information on Wikipedia). Our contribution highlights the key considerations needed for further developing a unifying concept of agro-biodiversity hotspots that encompasses multiple facets of diversity (including genetic and phylogenetic) and the linkage with overall biodiversity. This integration will ultimately enhance our understanding of the geography of human-plant interactions and help guide the preservation of nature and its contributions to people.

Plant Biodiversity and Genetic Resources Matter!

“…While biodiversity hotspots are mainly defined by species richness, agrobiodiversity hotspots refer to the centers of origin and diversity of (major) crops and their wild relatives, harboring genetic resources that are of high and increasing relevance for plant breeding. Pironon et al [8] observed spatial congruence between biodiversity and agrobiodiversity hotspots and proposed a unifying concept, taking into consideration not only species richness but also the multiple benefits plants offer to humankind in terms of ecosystem and agro-ecosystem functions, the inter-and intra-specific diversity of the chemical properties of plants for human nutrition and medicinal use, as well as the provision of gene sources for plant breeding. Rather than considering only major global food crops, agrobiodiversity conservation and use strategies should explicitly include the huge number of edible plants, which are currently underutilized and/or only of regional or often local importance, including wild food plants harvested in the wild that provide significant food and other benefits to humanity [19,20].…”

“…Several papers in this Special Issue have addressed genetic erosion aspects and provided suggestions and experiences regarding how this erosion can be stemmed for wild and cultivated biodiversity [8], CWR [3,21], wild food plants [19,20], vegetables [25], and forages [17].…”

“…However, public sector breeders in developing countries are still confronted with obstacles such as accessing germplasm across national borders and the lack of appropriate technologies and skills to exploit sets of germplasm accessions composed of landraces and CWR [41]. It has been proposed that the commonly used estimated breeding value (EBV) of a parent in a cross could be expanded from individuals to species and populations, and in this case go beyond mere heritability values to additionally include crossing considerations (e.g., ploidy, mating system), evolutionary factors (e.g., phylogenetic relationship), and ecological factors (e.g., environment the species is thriving in) [8]. This multi-pronged approach of an expanded EBV could be used to produce a ranking of species for an individual breeding program, based on the traits required for a desired phenotype.…”

“…encountered in Brazil. If we are serious about slowing down the on-going genetic erosion and saving those species which are threatened or close to extinction, as well as those currently still being discovered by science, whose potential is still unknown, it is mandatory to conserve the genetic diversity found especially in biodiversity hotspots of wild and domesticated biodiversity [8]. This will benefit current and future generations.…”

“…We encouraged contributions to this Special Issue on plant biodiversity and genetic resources in the form of original research and review papers with the aim to disseminate and promote knowledge on a wide array of aspects in this important field, which underpins sustainable agriculture and food and nutrition security in a globalized world, facing multiple challenges. This Special Issue comprises 32 papers covering a wide array of aspects from the definition and identification of hotspots of wild and domesticated plant biodiversity [8] to the specifics of the conservation of crop germplasm and their wild relatives in situ and ex situ, including germplasm and genebank management and genebank phenomics, to enhance the value and utilization of crop germplasm in breeding. The various modes of ex situ germplasm conservation in the form of orthodox seeds, as in vitro collections and/or in liquid nitrogen, have been described [5], and special attention has been drawn to the importance of seed physiology for the successful long-term conservation of orthodox seeds [4].…”