David E Williams | Independent Researcher (original) (raw)
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Papers by David E Williams
Bonplandia, 2009
Bolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación únic... more Bolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación único en el mundo, lo que señala a Bolivia como una importante fuente de materiales para el mejoramiento de este cultivo de importancia mundial. En este estudio para maní se diferencian para Bolivia 62 razas de maní cultivado de las cuales, 42 pertenecen a Arachis hypogaea L subsp. hypogaea var. hypogaea, 17 a A. hypogaea susbp. fastigiata Waldron var. fastigiata, 1 a A. hypogaea susbp. fastigiata var. vulgaris y 2 a A. hypogaea subsp. fastigiata var. peruviana Krapov. & W. C. Gregory. Bolivia constituye un centro de variación independiente pues sus razas son exclusivas de su territorio, salvo muy pocas excepciones. Bolivia como unidad, se caracteriza por las razas "Crema", "Colorado San Simón", "Bayo americano", "Overo" y "Overo carenado", que se cultivan en todo el país. Se pueden delimitar algunas regiones de mayor diversidad: la región de...
WCHR - World Conference on Horticultural Research, 1999
Plant Genetic Resources Newsletter, 2002
Domesticated crop plants and their related wild species represent the biological foundation upon ... more Domesticated crop plants and their related wild species represent the biological foundation upon which world food security is based, yet these important components of biological diversity are imminently threatened by genetic erosion in situ. Spatial analyses are used to assess three key issues for the conservation and use of wild peanut genetic resources:(1) spatial analyses at the genomic level to elucidate the geographic origin of the cultivated peanut,(2) climatic adaptation analysis for each species, and (3) prioritization modeling for ...
Biodiversity and Conservation, 2005
Geographic Information System (GIS) tools are applied to a comprehensive database of 3514 records... more Geographic Information System (GIS) tools are applied to a comprehensive database of 3514 records of wild Arachis species to assist in the conservation and utilisation of the species by: (a) determining the distributional range of species and their abundance; (b) characterising species environments; (c) determining the geographical distribution of species richness; and (d) determining the extent to which species are associated with river basins. Distributional ranges, climatic variables and indices of endemism for each species are tabulated. A. duranensis Krapov. & W.C. Gregory, the most probable donor of the A genome to the cultivated peanut, is distributed in close proximity to both the proposed donor of the B genome, A. ipae¨nsis, and the closest wild relative of the cultigen, A. monticola Krapov. & Rigoni. This region in the eastern foothills of the Andes and the adjoining chaco regions of Argentina, Bolivia and Paraguay, is a key area for further exploration for wild Arachis. An area of particularly high species richness occurs in the State of Mato Grosso, close to the Gran Pantanal in southwest Brazil. Seventy-one percent of the species were found to have some degree of association with water catchment areas, although in most cases it was difficult to determine whether this was due to climatic adaptation reasons, restricted dispersal due to geocarpic habit, or the role of watercourses as a principal dispersal agent. In only two cases could climatic adaptation be eliminated as the reason for species distribution.
Economic Botany, 1993
... Very little eth-nobotanical information regarding this species has been published, with the p... more ... Very little eth-nobotanical information regarding this species has been published, with the possible exception of the works of Francisco Hern/mdez (1651, 1790) and Martin de la Cruz (de la Cruz 1964; Emmart 1940; Gates 1939) which will be discussed later. ...
plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Oth... more plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Other estimates The conservation status of wild Arachis spp. is not well charactersuggest that 25 to 35% of plant genetic diversity could ized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives be lost in the next 20 yr. Those taxa that include crop were to use 2175 georeferenced observations of wild peanut (Arachis species and their wild relatives (crop gene pools) are of spp.) to assess the conservation status of the genus and to prioritize particular concern from a conservation perspective. The biologically and geographically future conservation actions. Species economic and social consequences of such an irredeemdistribution predictions were made on the basis of 36 climate variables, able loss of plant diversity, combined with rapid human and these data were synthesized with land-use data to map the potenpopulation growth, could be potentially disastrous. The tial distribution of each species, and hence the species richness of the conservation of plant diversity, particularly of those spewhole genus, excluding A. hypogea. hotspots of species richness were cies essential for human nutrition and crop improvefound in Mato Grosso around Cuiabá and Campo Grande in Brazil ment, is of critical importance. One of the most pressing and around the Serra Geral de Goias, northeast of Brasilia. The challenges facing biologists today is the description of current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. biological diversity at the ecosystem, species, and ge-Several species were identified as being under threat of extinction. netic level.
Brittonia, 1992
He played a significant role, not only in the founding of NYBG in 1891, but also in establishing ... more He played a significant role, not only in the founding of NYBG in 1891, but also in establishing a strong precedent of research and exploration in the field of economic botany at the new institution. As a result of Rusby's influence and activity, the study of useful plants formed an important part of NYBG's original mandate, an institutional commitment that was rejuvenated nearly a century later, with the formation of the Institute of Economic Botany. An indefatigable researcher both in the field and in the herbarium, Rusby left behind a voluminous corpus of published work in systematic and economic botany that is a legacy for modem botanists and pharmacologists.
PloS one, 2015
For most crops, like Capsicum, their diversity remains under-researched for traits of interest fo... more For most crops, like Capsicum, their diversity remains under-researched for traits of interest for food, nutrition and other purposes. A small investment in screening this diversity for a wide range of traits is likely to reveal many traditional varieties with distinguished values. One objective of this study was to demonstrate, with Capsicum as model crop, the application of indicators of phenotypic and geographic diversity as effective criteria for selecting promising genebank accessions for multiple uses from crop centers of diversity. A second objective was to evaluate the expression of biochemical and agromorphological properties of the selected Capsicum accessions in different conditions. Four steps were involved: 1) Develop the necessary diversity by expanding genebank collections in Bolivia and Peru; 2) Establish representative subsets of ~100 accessions for biochemical screening of Capsicum fruits; 3) Select promising accessions for different uses after screening; and 4) Ex...
Crop Science, 2003
plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Oth... more plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Other estimates The conservation status of wild Arachis spp. is not well charactersuggest that 25 to 35% of plant genetic diversity could ized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives be lost in the next 20 yr. Those taxa that include crop were to use 2175 georeferenced observations of wild peanut (Arachis species and their wild relatives (crop gene pools) are of spp.) to assess the conservation status of the genus and to prioritize particular concern from a conservation perspective. The biologically and geographically future conservation actions. Species economic and social consequences of such an irredeemdistribution predictions were made on the basis of 36 climate variables, able loss of plant diversity, combined with rapid human and these data were synthesized with land-use data to map the potenpopulation growth, could be potentially disastrous. The tial distribution of each species, and hence the species richness of the conservation of plant diversity, particularly of those spewhole genus, excluding A. hypogea. hotspots of species richness were cies essential for human nutrition and crop improvefound in Mato Grosso around Cuiabá and Campo Grande in Brazil ment, is of critical importance. One of the most pressing and around the Serra Geral de Goias, northeast of Brasilia. The challenges facing biologists today is the description of current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. biological diversity at the ecosystem, species, and ge-Several species were identified as being under threat of extinction. netic level.
Bonplandia, 2009
Bolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación únic... more Bolivia se destaca como probable lugar de origen del maní cultivado y un centro de variación único en el mundo, lo que señala a Bolivia como una importante fuente de materiales para el mejoramiento de este cultivo de importancia mundial. En este estudio para maní se diferencian para Bolivia 62 razas de maní cultivado de las cuales, 42 pertenecen a Arachis hypogaea L subsp. hypogaea var. hypogaea, 17 a A. hypogaea susbp. fastigiata Waldron var. fastigiata, 1 a A. hypogaea susbp. fastigiata var. vulgaris y 2 a A. hypogaea subsp. fastigiata var. peruviana Krapov. & W. C. Gregory. Bolivia constituye un centro de variación independiente pues sus razas son exclusivas de su territorio, salvo muy pocas excepciones. Bolivia como unidad, se caracteriza por las razas "Crema", "Colorado San Simón", "Bayo americano", "Overo" y "Overo carenado", que se cultivan en todo el país. Se pueden delimitar algunas regiones de mayor diversidad: la región de...
WCHR - World Conference on Horticultural Research, 1999
Plant Genetic Resources Newsletter, 2002
Domesticated crop plants and their related wild species represent the biological foundation upon ... more Domesticated crop plants and their related wild species represent the biological foundation upon which world food security is based, yet these important components of biological diversity are imminently threatened by genetic erosion in situ. Spatial analyses are used to assess three key issues for the conservation and use of wild peanut genetic resources:(1) spatial analyses at the genomic level to elucidate the geographic origin of the cultivated peanut,(2) climatic adaptation analysis for each species, and (3) prioritization modeling for ...
Biodiversity and Conservation, 2005
Geographic Information System (GIS) tools are applied to a comprehensive database of 3514 records... more Geographic Information System (GIS) tools are applied to a comprehensive database of 3514 records of wild Arachis species to assist in the conservation and utilisation of the species by: (a) determining the distributional range of species and their abundance; (b) characterising species environments; (c) determining the geographical distribution of species richness; and (d) determining the extent to which species are associated with river basins. Distributional ranges, climatic variables and indices of endemism for each species are tabulated. A. duranensis Krapov. & W.C. Gregory, the most probable donor of the A genome to the cultivated peanut, is distributed in close proximity to both the proposed donor of the B genome, A. ipae¨nsis, and the closest wild relative of the cultigen, A. monticola Krapov. & Rigoni. This region in the eastern foothills of the Andes and the adjoining chaco regions of Argentina, Bolivia and Paraguay, is a key area for further exploration for wild Arachis. An area of particularly high species richness occurs in the State of Mato Grosso, close to the Gran Pantanal in southwest Brazil. Seventy-one percent of the species were found to have some degree of association with water catchment areas, although in most cases it was difficult to determine whether this was due to climatic adaptation reasons, restricted dispersal due to geocarpic habit, or the role of watercourses as a principal dispersal agent. In only two cases could climatic adaptation be eliminated as the reason for species distribution.
Economic Botany, 1993
... Very little eth-nobotanical information regarding this species has been published, with the p... more ... Very little eth-nobotanical information regarding this species has been published, with the possible exception of the works of Francisco Hern/mdez (1651, 1790) and Martin de la Cruz (de la Cruz 1964; Emmart 1940; Gates 1939) which will be discussed later. ...
plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Oth... more plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Other estimates The conservation status of wild Arachis spp. is not well charactersuggest that 25 to 35% of plant genetic diversity could ized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives be lost in the next 20 yr. Those taxa that include crop were to use 2175 georeferenced observations of wild peanut (Arachis species and their wild relatives (crop gene pools) are of spp.) to assess the conservation status of the genus and to prioritize particular concern from a conservation perspective. The biologically and geographically future conservation actions. Species economic and social consequences of such an irredeemdistribution predictions were made on the basis of 36 climate variables, able loss of plant diversity, combined with rapid human and these data were synthesized with land-use data to map the potenpopulation growth, could be potentially disastrous. The tial distribution of each species, and hence the species richness of the conservation of plant diversity, particularly of those spewhole genus, excluding A. hypogea. hotspots of species richness were cies essential for human nutrition and crop improvefound in Mato Grosso around Cuiabá and Campo Grande in Brazil ment, is of critical importance. One of the most pressing and around the Serra Geral de Goias, northeast of Brasilia. The challenges facing biologists today is the description of current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. biological diversity at the ecosystem, species, and ge-Several species were identified as being under threat of extinction. netic level.
Brittonia, 1992
He played a significant role, not only in the founding of NYBG in 1891, but also in establishing ... more He played a significant role, not only in the founding of NYBG in 1891, but also in establishing a strong precedent of research and exploration in the field of economic botany at the new institution. As a result of Rusby's influence and activity, the study of useful plants formed an important part of NYBG's original mandate, an institutional commitment that was rejuvenated nearly a century later, with the formation of the Institute of Economic Botany. An indefatigable researcher both in the field and in the herbarium, Rusby left behind a voluminous corpus of published work in systematic and economic botany that is a legacy for modem botanists and pharmacologists.
PloS one, 2015
For most crops, like Capsicum, their diversity remains under-researched for traits of interest fo... more For most crops, like Capsicum, their diversity remains under-researched for traits of interest for food, nutrition and other purposes. A small investment in screening this diversity for a wide range of traits is likely to reveal many traditional varieties with distinguished values. One objective of this study was to demonstrate, with Capsicum as model crop, the application of indicators of phenotypic and geographic diversity as effective criteria for selecting promising genebank accessions for multiple uses from crop centers of diversity. A second objective was to evaluate the expression of biochemical and agromorphological properties of the selected Capsicum accessions in different conditions. Four steps were involved: 1) Develop the necessary diversity by expanding genebank collections in Bolivia and Peru; 2) Establish representative subsets of ~100 accessions for biochemical screening of Capsicum fruits; 3) Select promising accessions for different uses after screening; and 4) Ex...
Crop Science, 2003
plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Oth... more plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Other estimates The conservation status of wild Arachis spp. is not well charactersuggest that 25 to 35% of plant genetic diversity could ized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives be lost in the next 20 yr. Those taxa that include crop were to use 2175 georeferenced observations of wild peanut (Arachis species and their wild relatives (crop gene pools) are of spp.) to assess the conservation status of the genus and to prioritize particular concern from a conservation perspective. The biologically and geographically future conservation actions. Species economic and social consequences of such an irredeemdistribution predictions were made on the basis of 36 climate variables, able loss of plant diversity, combined with rapid human and these data were synthesized with land-use data to map the potenpopulation growth, could be potentially disastrous. The tial distribution of each species, and hence the species richness of the conservation of plant diversity, particularly of those spewhole genus, excluding A. hypogea. hotspots of species richness were cies essential for human nutrition and crop improvefound in Mato Grosso around Cuiabá and Campo Grande in Brazil ment, is of critical importance. One of the most pressing and around the Serra Geral de Goias, northeast of Brasilia. The challenges facing biologists today is the description of current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. biological diversity at the ecosystem, species, and ge-Several species were identified as being under threat of extinction. netic level.