- 321 Birge Hall / Botany Department
430 Lincoln Drive
Madison, Wisconsin 53706 - Office phone: 608-890-1170
Eve Emshwiller
University of Wisconsin-Madison, Botany, Faculty Member
- Conservation Genetics, Botany, Ethnobotany, Agriculture (Biology), Evolutionary Biology, Ethnobiology, and 27 moreSystematic Biology, Plant Systematics, Sustainable Agriculture (Sustainability), Food History, Plant domestication (Prehistoric Archaeology), Agricultural Biodiversity, Mountain communities, Conservation Biology, Biodiversity, Molecular Markers, Agricultural Botany, Ethnobotany in South America, Flow Cytometry, Molecular Systematics, Agroecology, Clonal Plants, South America (Archaeology), North American (Archaeology), Indigeneous Peoples of South America, Traditional Ecological Knowledge, Molecular Phylogenetics and Evolution, Polyploids, Andean underutilized crops, Crop genetic diversity, Paleoethnobotany (Anthropology), Anthropology of Food, and Etnobotánicaedit
- Eve Emshwiller’s research interests center on the ethnobotany, evolution, and conservation of crop plants and their w... moreEve Emshwiller’s research interests center on the ethnobotany, evolution, and conservation of crop plants and their wild relatives. Her research has focused principally on the domestication, the origin of polyploidy, and the ongoing evolution of the Andean tuber crop “oca,” Oxalis tuberosa, and its wild allies. Her current research includes an international collaborative project on phylogeny of the genus Oxalis and a study of the distribution of clonal genotypes of cultivated oca as an example of the evolution of clonally-propagated crops under human influence. She is currently collaborating with the Bolivian National Germplasm Bank to help expand their collection of crop wild relatives. She has been a member of the faculty of the Department of Botany at University of Wisconsin - Madison since 2006. Previously she was Adjunct Curator of Economic Botany at the Field Museum in Chicago for ~7.5 years. Between her two stints as a student at Cornell (graduate student in the 1990s, undergrad in the mid-1970s), she lived in Maine for 12 years and worked in gardens and greenhouses. Most of her field work to date has been conducted in the central Andean region, including a student Fulbright year in Peru in 1996-7 and an ongoing Serial Fulbright Scholar Grant in Bolivia (3 segments from 2013 to 2016). She has been active in the Society for Economic Botany, including serving as its 2009-2010 president.edit
Mary Saunders Bulan, Jiangchong Wu, Eve Emshwiller, Mark E. Berres, Joshua L. Posner, Duoyi Peng, Xinhui Wang, Junfang Li, David E. Stoltenberg, Yanping Zhang (2015) Social and environmental influences on tartary buckwheat (Fagopyrum... more
Mary Saunders Bulan, Jiangchong Wu, Eve Emshwiller, Mark E. Berres, Joshua L. Posner, Duoyi Peng, Xinhui Wang, Junfang Li, David E. Stoltenberg, Yanping Zhang (2015) Social and environmental influences on tartary buckwheat
(Fagopyrum tataricum Gaertn.) varietal diversity in Yunnan,
China Genet Resour Crop Evol DOI 10.1007/s10722-015-0337-0
Effective conservation strategies aimed to protect crop genetic resources require multiple sources of information. We used a combination of AFLP genotyping and farmer surveys to understand the extent, distribution and management of tartary buckwheat (Fagopyrum tataricum Gaertn.) diversity in its center of origin in Yunnan Province, China. We found genetic evidence of gene flow in tartary buckwheat throughout the study area, with small but statistically significant regional and village-level components. We also found genetic differentiation by seed color. Although most farmers reported exchanging seed in localized kinship networks, our results imply homogenizing gene flow is occurring. Yi ethnic farmers tend to plant more buckwheat than non-Yi farmers, and we found that in some communities, Yi farmers serve as seed sources for farmers of other ethnicities. Different tartary buckwheat varieties did not have different end uses; rather farmers maintained varietal diversity in order to protect crop yield and quality. Individual farmers’ seed exchange practices reflect their ideas about components of seed quality, as well as priorities in protecting buckwheat yield. From the standpoint of genetic resources conservation, the presence of a culturally rich farmer exchange network and hierarchical structuring of tartary buckwheat genetic diversity demonstrates the importance of maintaining an interlinked community of tartary buckwheat farmers in Yunnan.
(Fagopyrum tataricum Gaertn.) varietal diversity in Yunnan,
China Genet Resour Crop Evol DOI 10.1007/s10722-015-0337-0
Effective conservation strategies aimed to protect crop genetic resources require multiple sources of information. We used a combination of AFLP genotyping and farmer surveys to understand the extent, distribution and management of tartary buckwheat (Fagopyrum tataricum Gaertn.) diversity in its center of origin in Yunnan Province, China. We found genetic evidence of gene flow in tartary buckwheat throughout the study area, with small but statistically significant regional and village-level components. We also found genetic differentiation by seed color. Although most farmers reported exchanging seed in localized kinship networks, our results imply homogenizing gene flow is occurring. Yi ethnic farmers tend to plant more buckwheat than non-Yi farmers, and we found that in some communities, Yi farmers serve as seed sources for farmers of other ethnicities. Different tartary buckwheat varieties did not have different end uses; rather farmers maintained varietal diversity in order to protect crop yield and quality. Individual farmers’ seed exchange practices reflect their ideas about components of seed quality, as well as priorities in protecting buckwheat yield. From the standpoint of genetic resources conservation, the presence of a culturally rich farmer exchange network and hierarchical structuring of tartary buckwheat genetic diversity demonstrates the importance of maintaining an interlinked community of tartary buckwheat farmers in Yunnan.
Research Interests:
Georgian, Elizabeth, Zhendong Fang, Eve Emshwiller, Anna Pidgeon. (2015) The Pollination Ecology of Rhododendron floccigerum Franchet (Ericaceae) in Weixi, Yunnan Province, China. Journal of Pollination Ecology. 16(11):72-81.... more
Georgian, Elizabeth, Zhendong Fang, Eve Emshwiller, Anna Pidgeon. (2015) The Pollination Ecology of Rhododendron floccigerum Franchet (Ericaceae) in Weixi, Yunnan Province, China. Journal of Pollination Ecology. 16(11):72-81. http://www.pollinationecology.org/index.php?journal=jpe&page=article&op=view&path[]=330&path[]=116
Identifying the pollinators of Rhododendron species is of great interest due to potential conservation threats in the native range of the genus, but the pollinators of species in Rhododendron subgenus Hymenanthes section Pontica subsection Neriiflora are unknown. Bees (Hymenoptera; family Apidae) are thought to be the pollinators of many Rhododendron species; however, species in subsection Neriiflora have ornithophilous floral morphology. We studied R. floccigerum (subsection Neriiflora) to determine the identities of visiting, potentially pollinating, and robbing species through in-person and time lapsed camera trap observations. We compared floral morphological characteristics of R. floccigerum with visitor morphological measurements to determine if visitors could fit inside the corolla. Thirteen species were observed visiting R. floccigerum (two insects, two mammals, and nine birds) and this study provides the first empirical evidence of both bird and mammal visitors to Rhododendron species. We determined that the following species are potential pollinators: Bombus sp. (an insect genus), Aethopyga gouldiae, Garrulax affinis, Heterophasia melanoleuca, and Yuhinia diademata (all bird species), and we suspect that Apis sp. (an insect genus), Dremomys pernyi, Tamiops swinhoei (two mammal species), Minla ignotincta, M. strigula, Parus major, and Phylloscopus affinis (four bird species) likely rob R. floccigerum. All visitors were able to fit their heads/bodies into the corolla. We also found that though predation is frequent, the number of robbers and variety of robbing methods is unlikely to contribute to floral morphological evolution or speciation. Further understanding of the pollination biology of species in subgenus Hymenanthes will allow for effective conservation.
Identifying the pollinators of Rhododendron species is of great interest due to potential conservation threats in the native range of the genus, but the pollinators of species in Rhododendron subgenus Hymenanthes section Pontica subsection Neriiflora are unknown. Bees (Hymenoptera; family Apidae) are thought to be the pollinators of many Rhododendron species; however, species in subsection Neriiflora have ornithophilous floral morphology. We studied R. floccigerum (subsection Neriiflora) to determine the identities of visiting, potentially pollinating, and robbing species through in-person and time lapsed camera trap observations. We compared floral morphological characteristics of R. floccigerum with visitor morphological measurements to determine if visitors could fit inside the corolla. Thirteen species were observed visiting R. floccigerum (two insects, two mammals, and nine birds) and this study provides the first empirical evidence of both bird and mammal visitors to Rhododendron species. We determined that the following species are potential pollinators: Bombus sp. (an insect genus), Aethopyga gouldiae, Garrulax affinis, Heterophasia melanoleuca, and Yuhinia diademata (all bird species), and we suspect that Apis sp. (an insect genus), Dremomys pernyi, Tamiops swinhoei (two mammal species), Minla ignotincta, M. strigula, Parus major, and Phylloscopus affinis (four bird species) likely rob R. floccigerum. All visitors were able to fit their heads/bodies into the corolla. We also found that though predation is frequent, the number of robbers and variety of robbing methods is unlikely to contribute to floral morphological evolution or speciation. Further understanding of the pollination biology of species in subgenus Hymenanthes will allow for effective conservation.
Research Interests:
Walsh, Brian M., Dinesh Adhikary, Peter J. Maughan, Eve Emshwiller, and Eric N. Jellen. (2015) Chenopodium (Amaranthaceae) polyploidy inferences from Salt Overly Sensitive 1 (SOS1) data. American Journal of Botany. 102 (40): 533-543
Research Interests:
Research Interests:
Research Interests:
Shared and Separate Knowledge among Eight Cultural Groups Based on Ethnobotanical Uses of Rhododendron (Ericaceae) in Yunnan Province, China. Yunnan, a province in southwest China, is known for its cultural diversity of 25 ethnic... more
Shared and Separate Knowledge among Eight Cultural Groups Based on Ethnobotanical Uses of Rhododendron (Ericaceae) in Yunnan Province, China.
Yunnan, a province in southwest China, is known for its cultural diversity of 25 ethnic minorities and its vast Himalayan biodiversity, especially of Rhododendron. Previous literature has shown that some cultural groups share ethnobotanical knowledge while other cultural groups keep their knowledge separate. We investigated factors that may lead to the sharing of knowledge based on the uses of rhododendron among seven cultural minorities (the Bai, Dulong, Lisu, Naxi, Nu, Tibetan, and Yi) and the Han majority. Semistructured interviews about rhododendrons were conducted with approximately 30 individuals in each cultural group. Cluster analyses and a new analysis method were conducted to determine the within-group homogeneity of knowledge of rhododendron uses to test hypotheses related to strength of cultural traditions. The Dulong, Lisu, and Nu were compared with each other as these groups share villages and languages. The Naxi, Tibetan, and Yi live predominantly with members of their cultural group, and are often monolingual; thus, these three cultural minorities were compared. The Bai and Han compose the final comparison as the Bai are increasingly interacting with the local Han majority as tourism grows in that area. The Bai, Dulong, Han, Lisu, and Nu had variable answers within each group, while the Naxi, Tibetan, and Yi have homogeneous knowledge of uses of rhododendron within their cultural group. Among the eight cultural groups compared for this study, factors such as sharing of language, overlap of living situation, and sharing of markets leads to non-homogenous knowledge of rhododendron uses among members of the same cultural group.
中国云南省八个民族对杜鹃花属植物认识与利用的共性及差异.
中国南部的云南省位于喜马拉雅区域,拥有25个少数民族,以其丰富的文化多样性和以杜鹃花属植物为代表的生物多样性闻名于世。前人的研究表明一些民族之间在民族植物学的常识方面存在共性,而另一些民族在这些方面却有独立的认识。通过对每个民族中约30人的半结构访谈,我们在七个少数民族(白族、独龙族、傈僳族、纳西族、怒族、藏族、彝族)和人数众多的汉族共八个民族之间进行了杜鹃花利用方式和此类知识在民族之间共享原因的调查。聚类分析和一种新的分析方法被用于评估同种民族内杜鹃花利用方式和相关知识的差异程度,以显示对文化传统的继承强度。独龙族、傈僳族和怒族因具有共同居住的村庄和共通的语言,因此对三者进行比较。纳西族、藏族和彝族各自为居,并且有独立的语言,因此在它们之间进行比较。另外比较的是白族和汉族,随着当地旅游业的发展,白族越来越多的与汉族之间产生相互影响。结果表明,白族、独龙族、汉族、傈僳族和怒族在本民族内部对于杜鹃花属植物有多样化的认识和不同的利用方式;而纳西族、藏族、彝族对杜鹃花属植物的认识和利用具有民族内部的一致性。在本研究涉及的八个民族中,语言共通程度、居住地重叠、共用农贸市场等因素导致了相同民族内部对杜鹃花属植物认识和利用的差异。
Yunnan, a province in southwest China, is known for its cultural diversity of 25 ethnic minorities and its vast Himalayan biodiversity, especially of Rhododendron. Previous literature has shown that some cultural groups share ethnobotanical knowledge while other cultural groups keep their knowledge separate. We investigated factors that may lead to the sharing of knowledge based on the uses of rhododendron among seven cultural minorities (the Bai, Dulong, Lisu, Naxi, Nu, Tibetan, and Yi) and the Han majority. Semistructured interviews about rhododendrons were conducted with approximately 30 individuals in each cultural group. Cluster analyses and a new analysis method were conducted to determine the within-group homogeneity of knowledge of rhododendron uses to test hypotheses related to strength of cultural traditions. The Dulong, Lisu, and Nu were compared with each other as these groups share villages and languages. The Naxi, Tibetan, and Yi live predominantly with members of their cultural group, and are often monolingual; thus, these three cultural minorities were compared. The Bai and Han compose the final comparison as the Bai are increasingly interacting with the local Han majority as tourism grows in that area. The Bai, Dulong, Han, Lisu, and Nu had variable answers within each group, while the Naxi, Tibetan, and Yi have homogeneous knowledge of uses of rhododendron within their cultural group. Among the eight cultural groups compared for this study, factors such as sharing of language, overlap of living situation, and sharing of markets leads to non-homogenous knowledge of rhododendron uses among members of the same cultural group.
中国云南省八个民族对杜鹃花属植物认识与利用的共性及差异.
中国南部的云南省位于喜马拉雅区域,拥有25个少数民族,以其丰富的文化多样性和以杜鹃花属植物为代表的生物多样性闻名于世。前人的研究表明一些民族之间在民族植物学的常识方面存在共性,而另一些民族在这些方面却有独立的认识。通过对每个民族中约30人的半结构访谈,我们在七个少数民族(白族、独龙族、傈僳族、纳西族、怒族、藏族、彝族)和人数众多的汉族共八个民族之间进行了杜鹃花利用方式和此类知识在民族之间共享原因的调查。聚类分析和一种新的分析方法被用于评估同种民族内杜鹃花利用方式和相关知识的差异程度,以显示对文化传统的继承强度。独龙族、傈僳族和怒族因具有共同居住的村庄和共通的语言,因此对三者进行比较。纳西族、藏族和彝族各自为居,并且有独立的语言,因此在它们之间进行比较。另外比较的是白族和汉族,随着当地旅游业的发展,白族越来越多的与汉族之间产生相互影响。结果表明,白族、独龙族、汉族、傈僳族和怒族在本民族内部对于杜鹃花属植物有多样化的认识和不同的利用方式;而纳西族、藏族、彝族对杜鹃花属植物的认识和利用具有民族内部的一致性。在本研究涉及的八个民族中,语言共通程度、居住地重叠、共用农贸市场等因素导致了相同民族内部对杜鹃花属植物认识和利用的差异。
Research Interests:
Beck, Stephan G. and Eve Emshwiller. (2014). Hypseocharitaceae. In: P. M. Jørgensen et al. (eds.), Catálogo de las Plantas Vasculares de Bolivia. Missouri Botanical Garden Press. Volume 1: 728.
Research Interests:
Research Interests:
Oxalis sections Corniculatae DC. and Ripariae Lourteig are composed mainly of creeping herbs. They not only share strong morphological similarities, such as the presence of a reptant stem but also some cytogenetic characteristics. Several... more
Oxalis sections Corniculatae DC. and Ripariae Lourteig are composed mainly of creeping herbs. They not only share strong morphological similarities, such as the presence of a reptant stem but also some cytogenetic characteristics. Several species in section Corniculatae share a base chromosome number x = 5 with species in section Ripariae, while other species in the former have a x = 6. We used a molecular and cytogenetic approach to determine the phylogenetic relationships, test the previous taxonomic classification and study the genome rearrangements that led to the differences in chromosome size and basic chromosome number between both sections. Phylogenetic relationships were inferred based on DNA sequences from chloroplast and nuclear ribosomal ITS. The molecular phylogenetic analyses found that neither of the sections are monophyletic, but do support two clades. The first group contains diploid species with x = 5, large chromosomes and high DNA content and the second diploid and polyploidy species with x = 6, small chromosomes and low DNA content. The x = 5 clade comprises species of both sections, while the x = 6 clade was formed mainly by section Corniculatae species and O. serpens from section Ripariae. Our results suggest that x = 5 and high DNA content are derived conditions, which may have resulted from descendent disploidy and proliferation of transposable elements. Thus, cytogenetic data superimposed on the phylogeny have shown two different modes of chromosome evolution in both lineages: (1) chromosome rearrangements and increase in genome size in the x = 5 lineage and (2) polyploidy playing the main role in chromosome evolution among species in the x = 6 species. A taxonomic revision for the two sections is suggested.
Research Interests:
"• Premise of the study: Manioc (Manihot esculenta subsp. esculenta), one of the most important tropical food crops, is commonly divided according to cyanide content into two use-categories, “sweet” and “bitter.” While bitter and sweet... more
"• Premise of the study: Manioc (Manihot esculenta subsp. esculenta), one of the most important tropical food crops, is commonly divided according to cyanide content into two use-categories, “sweet” and “bitter.” While bitter and sweet varieties are genetically differentiated at the local scale, whether this differentiation is consistent across continents is yet unknown.
• Methods: Using eight microsatellite loci, we genotyped 522 manioc samples (135 bitter and 387 sweet) from Ecuador, French Guiana, Cameroon, Gabon, Ghana, and Vanuatu. Genetic differentiation between use-categories was assessed using double principal coordinate analyses (DPCoA) with multivariate analysis of variance (MANOVA) and Jost’s measure of estimated differentiation (Dest). Genetic structure was analyzed using Bayesian clustering analysis.
• Key results: Manioc neutral genetic diversity was high in all sampled regions. Sweet and bitter manioc landraces are differentiated in South America but not in Africa. Correspondingly, bitter and sweet manioc samples share a higher proportion of neutral alleles in Africa than in South America. We also found seven clones classified by some farmers as sweet and by others as bitter.
• Conclusions: Lack of differentiation in Africa is most likely due to postintroduction hybridization between bitter and sweet manioc. Inconsistent transfer from South America to Africa of ethnobotanical knowledge surrounding use-category management may contribute to increased hybridization in Africa. Investigating this issue requires more data on the variation in cyanogenesis in roots within and among manioc populations and how manioc diversity is managed on the farm. "
• Methods: Using eight microsatellite loci, we genotyped 522 manioc samples (135 bitter and 387 sweet) from Ecuador, French Guiana, Cameroon, Gabon, Ghana, and Vanuatu. Genetic differentiation between use-categories was assessed using double principal coordinate analyses (DPCoA) with multivariate analysis of variance (MANOVA) and Jost’s measure of estimated differentiation (Dest). Genetic structure was analyzed using Bayesian clustering analysis.
• Key results: Manioc neutral genetic diversity was high in all sampled regions. Sweet and bitter manioc landraces are differentiated in South America but not in Africa. Correspondingly, bitter and sweet manioc samples share a higher proportion of neutral alleles in Africa than in South America. We also found seven clones classified by some farmers as sweet and by others as bitter.
• Conclusions: Lack of differentiation in Africa is most likely due to postintroduction hybridization between bitter and sweet manioc. Inconsistent transfer from South America to Africa of ethnobotanical knowledge surrounding use-category management may contribute to increased hybridization in Africa. Investigating this issue requires more data on the variation in cyanogenesis in roots within and among manioc populations and how manioc diversity is managed on the farm. "
Research Interests:
Premise of the study: The American bulb-bearing Oxalis (Oxalidaceae) have diverse heterostylous breeding systems and are distributed in mountainous areas from Patagonia to the northeastern United States. To study the evolutionary... more
Premise of the study: The American bulb-bearing Oxalis (Oxalidaceae) have diverse heterostylous breeding systems and are distributed in mountainous areas from Patagonia to the northeastern United States. To study the evolutionary processes leading to this diversity we construct the first molecular phylogeny for the American bulb-bearing Oxalis, using it to infer biogeographic history and breeding system evolution.
Methods: We use DNA sequence data (nrITS, trnL-trnL-trnF, trnT-trnL, and psbJ-petA) to infer phylogenetic history via parsimony, likelihood, and Bayesian analyses. We use Bayes Multistate to infer ancestral geographic distributions at well-supported nodes of the phylogeny. The Shimodaira-Hasegawa (SH) test distinguishes among hypotheses of single or multiple transitions from South America to North America, and tristyly to distyly.
Key Results: The American bulb-bearing Oxalis include sampled members of sections Ionoxalis and Pseudobulbosae, and are derived from a larger clade including members of sections Palmatifoliae, Articulatae and the African species. The American bulb-bearing Oxalis comprise two clades: one distributed in SE South America, the other in the Andes and North America. An SH test supports multiple dispersals to North America. Most sampled distylous species form a single clade, but there are at least two other, independent distylous lineages, supported by the SH tests.
Conclusions: Phylogenetic results suggest the American bulb-bearing Oxalis originated in southern South America, dispersed repeatedly to North America, and had multiple transitions from tristyly to distyly. This study adds to our understanding of biogeographic history and breeding system evolution and provides a foundation for more precise inferences about the study group.
Methods: We use DNA sequence data (nrITS, trnL-trnL-trnF, trnT-trnL, and psbJ-petA) to infer phylogenetic history via parsimony, likelihood, and Bayesian analyses. We use Bayes Multistate to infer ancestral geographic distributions at well-supported nodes of the phylogeny. The Shimodaira-Hasegawa (SH) test distinguishes among hypotheses of single or multiple transitions from South America to North America, and tristyly to distyly.
Key Results: The American bulb-bearing Oxalis include sampled members of sections Ionoxalis and Pseudobulbosae, and are derived from a larger clade including members of sections Palmatifoliae, Articulatae and the African species. The American bulb-bearing Oxalis comprise two clades: one distributed in SE South America, the other in the Andes and North America. An SH test supports multiple dispersals to North America. Most sampled distylous species form a single clade, but there are at least two other, independent distylous lineages, supported by the SH tests.
Conclusions: Phylogenetic results suggest the American bulb-bearing Oxalis originated in southern South America, dispersed repeatedly to North America, and had multiple transitions from tristyly to distyly. This study adds to our understanding of biogeographic history and breeding system evolution and provides a foundation for more precise inferences about the study group.
Research Interests:
Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of polyploidy. To complement other studies of the origins of polyploidy of the octoploid tuber... more
Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of polyploidy. To complement other studies of the origins of polyploidy of the octoploid tuber crop oca (Oxalis tuberosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of domestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. picchensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca’s progenitor.
Research Interests:
Research Interests:
Economic development in southwest China and the increasing use of traditional Chinese medicine (TCM) worldwide have led to intensified collection of native medicinal plants. Fritillaria cirrhosa D. Don (Chuan Bei Mu), commonly used for... more
Economic development in southwest China and the increasing use of traditional Chinese medicine (TCM) worldwide have led to intensified collection of native medicinal plants. Fritillaria cirrhosa D. Don (Chuan Bei Mu), commonly used for the treatment of cough in TCM, is endemic to the Hengduan Mountain region of southwest China and is under increasing pressure from over-collection and decreasing suitable alpine habitat. The bioactive compounds in F. cirrhosa bulbs, isosteroidal alkaloids, are greatly influenced by environmental conditions and fluctuate in content and concentration with plant age and reproductive stage. Aiming at obtaining useful information for the sustainable management of wild F. cirrhosa populations, we evaluated how the phytochemical composition of F. cirrhosa bulbs varies at various stages of plant reproductive development. Using chemical methods and high performance liquid chromatography, two major bioactive alkaloids were extracted and analyzed from F. cirrhosa bulb samples collected throughout the Hengduan Mountain region. Plant reproductive stage was found to affect the concentration of bioactive alkaloids in F. cirrhosa bulbs. Bulb alkaloid concentration was highest during the early stages of fruit development and decreased significantly with fruit maturation. These results lend biochemical support to the practice of harvesting F. cirrhosa during the early stages of plant senescence (i.e., early fruit development).
Research Interests:
The origins and monophyly of the bulbous habit in the eudicot genus Oxalis are uncertain, but key character state transitions in the evolution of true bulbs are currently thought to be reflected in extant pseudobulbous and other... more
The origins and monophyly of the bulbous habit in the eudicot genus Oxalis are uncertain, but key character state transitions in the evolution of true bulbs are currently thought to be reflected in extant pseudobulbous and other geophytic taxa. We test the relationships between the two major groups of bulbous Oxalis taxa, namely the southern African lineage which is centered in the speciose Cape Floristic Region (CFR), and the New World section Ionoxalis, by including the rhizomatous geophyte Oxalis acetosella, the caudiciform stem succulent Oxalis articulata, and the rhizomiform pseudobulbous Oxalis triangularis, in combined phylogenetic analyses of nrITS and trnL-F sequence data. We optimize several key bulbous characters in ancestral state reconstructions on produced phylogenies. Results of our analyses indicate that the evolution of bulbous characters in the genus is more complex than previously thought. Although the two major bulb types are homologous, the rhizomiform pseudobulbous habit arises from within true bulbs, and in most reconstructions the caudiciform stem succulent O. articulata is inferred to have secondarily lost several distinctive bulbous characters. O. acetosella is not as closely related to the bulbous lineage as previously thought. More sampling from other key taxa are needed before the order in which key bulbous characters were acquired can be verified. We discuss these results in terms of the taxonomic and ecological implications for the CFR Oxalis taxa.
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The Role of Organic Acids in the Domestication of Oxalis tuberosa: A New Model for Studying Domestication Resulting in Opposing Crop Phenotypes. Though few crops display directly opposing domesticated phenotypes, these crops may be the... more
The Role of Organic Acids in the Domestication of Oxalis tuberosa: A New Model for Studying Domestication Resulting in Opposing Crop Phenotypes. Though few crops display directly opposing domesticated phenotypes, these crops may be the key to understanding domestication processes that address conflicting selective pressures in the agricultural ecosystem. Two relatively well-known examples are cassava (Manihot esculenta Crantz), which has high-cyanide and low-cyanide varieties, and potato (Solanum section Petota). Among the potatoes are several species, including the common potato (Solanum tuberosum L.), that have low levels of glycoalkaloids and there are other species of “bitter potato” with elevated levels of glycoalkaloids. We propose that Oxalis tuberosa Molina, “oca,” may represent a third example of such a crop system, with opposing high organic acid and low organic acid cultivars. Each cultivar set has different cultural food preparation practices (“use-categories”), similar to the “use-categories” that have been described for potatoes in the Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Our initial analyses suggest that organic acids in tubers may be an important biochemical difference between use-categories, based on both oxalic acid and pH data. Here, we review our understanding of organic acids in oca tubers, while highlighting areas that merit further investigation.
Los ácidos orgánicos y la domesticación de Oxalis tuberosa: un nuevo modelo para el estudio de la domesticación que resulta en los fenotipos domésticos opuestos. Aunque pocos cultivos presentan fenotipos domésticos directamente opuestos , estos cultivos pueden ser la clave para entender los procesos de domesticación que muestran conflicto en la presión selectiva en el ecosistema agrícola. Dos ejemplos relativamente bien conocidos son la yuca (Manihot esculenta Crantz), que tiene variedades de alto y bajo contenido de cianuro, y la papa (Solanum sección Petota). Entre las papas hay varias especies, incluyendo la papa común (Solanum tuberosum L.), que tienen bajos niveles de glicoalcaloides mientras otras especies como las "papas amargas", tienen elevados niveles de glicoalcaloides. Nosotros proponemos que Oxalis tuberosa Molina, oca, puede representar un tercer ejemplo de este sistema de cultivo, con niveles altos y bajos de ácidos orgánicos. Cada grupo de variedades de oca tiene diferentes practicas culturales respecto a su preparación como alimentos (categorías de uso), similar a las categorías de uso que se han descrito para las papas en los Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Los análisis iniciales sugieren que los ácidos orgánicos en los tubérculos pueden deberse a una diferencia bioquímica importante entre el uso de categorías basadas en el ácido oxálico y los datos de pH. En este artículo examinamos nuestra interpretación de los ácidos orgánicos en los tubérculos de oca, además de destacar las áreas que merecen mayor investigación.
Los ácidos orgánicos y la domesticación de Oxalis tuberosa: un nuevo modelo para el estudio de la domesticación que resulta en los fenotipos domésticos opuestos. Aunque pocos cultivos presentan fenotipos domésticos directamente opuestos , estos cultivos pueden ser la clave para entender los procesos de domesticación que muestran conflicto en la presión selectiva en el ecosistema agrícola. Dos ejemplos relativamente bien conocidos son la yuca (Manihot esculenta Crantz), que tiene variedades de alto y bajo contenido de cianuro, y la papa (Solanum sección Petota). Entre las papas hay varias especies, incluyendo la papa común (Solanum tuberosum L.), que tienen bajos niveles de glicoalcaloides mientras otras especies como las "papas amargas", tienen elevados niveles de glicoalcaloides. Nosotros proponemos que Oxalis tuberosa Molina, oca, puede representar un tercer ejemplo de este sistema de cultivo, con niveles altos y bajos de ácidos orgánicos. Cada grupo de variedades de oca tiene diferentes practicas culturales respecto a su preparación como alimentos (categorías de uso), similar a las categorías de uso que se han descrito para las papas en los Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Los análisis iniciales sugieren que los ácidos orgánicos en los tubérculos pueden deberse a una diferencia bioquímica importante entre el uso de categorías basadas en el ácido oxálico y los datos de pH. En este artículo examinamos nuestra interpretación de los ácidos orgánicos en los tubérculos de oca, además de destacar las áreas que merecen mayor investigación.
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Domestication, a process of increasing mutual dependence between human societies and the plant and animal populations they target, has long been an area of interest in genetics and archaeology. Geneticists seek out markers of... more
Domestication, a process of increasing mutual dependence between human societies and the plant and animal populations they target, has long been an area of interest in genetics and archaeology. Geneticists seek out markers of domestication in the genomes of domesticated species, both past and present day. Archaeologists examine the archaeological record for complementary markers – evidence of the human behavior patterns that cause the genetic changes associated with domestication, and the morphological changes in target species that result from them. In this article, we summarize the recent advances in genetics and archaeology in documenting plant and animal domestication, and highlight several promising areas where the complementary perspectives of both disciplines provide reciprocal illumination.
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In continuing study of the origins of the octoploid tuber crop oca, Oxalis tuberosa Molina, we used phylogenetic analysis of DNA sequences of the chloroplast-active (nuclear encoded) isozyme of glutamine synthetase (ncpGS) from cultivated... more
In continuing study of the origins of the octoploid tuber crop oca, Oxalis tuberosa Molina, we used phylogenetic analysis of DNA sequences of the chloroplast-active (nuclear encoded) isozyme of glutamine synthetase (ncpGS) from cultivated oca, its allies in the "Oxalis tuberosa alliance," and other Andean Oxalis. Multiple ncpGS sequences found within individuals of both the cultigen and a yet unnamed wild tuber-bearing taxon of Bolivia were separated by molecular cloning, but some cloned sequences appeared to be artifacts of polymerase chain reaction (PCR) recombination and/or Taq error. Nonetheless, three classes of nonrecombinant sequences each joined a different part of the O. tuberosa alliance clade on the ncpGS gene tree. Octoploid oca shares two sequence classes with the Bolivian tuber-bearing taxon (of unknown ploidy level). Fixed heterozygosity of these two sequence classes in all ocas sampled suggests that they represent homeologous loci and that oca is allopolyploid. A third sequence class, found in eight of nine oca plants sampled, might represent a third homeologous locus, suggesting that oca may be autoallopolyploid, and is shared with another wild tuber-bearing species, tetraploid O. picchensis of southern Peru. Thus, ncpGS data identify these two taxa as the best candidates as progenitors of cultivated oca.
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The ‘Oxalis tuberosa alliance’ is a group of Andean Oxalis species allied to the Andean tuber crop O. tuberosa Molina (Oxalidaceae), commonly known as ‘oca’. As part of a larger project studying the origins of polyploidy and... more
The ‘Oxalis tuberosa alliance’ is a group of Andean Oxalis species allied to the Andean tuber crop O. tuberosa Molina (Oxalidaceae), commonly known as ‘oca’. As part of a larger project studying the origins of polyploidy and domestication of cultivated oca, flow cytometry was used to survey DNA ploidy levels among Bolivian and Peruvian accessions of alliance members. In addition, this study provided a first assessment of C‐values in the alliance by estimating nuclear DNA contents of these accessions using chicken erythrocytes as internal standard. Ten Bolivian accessions of cultivated O. tuberosa were confirmed to be octoploid, with a mean nuclear DNA content of approx. 3·6 pg/2C. Two Peruvian wild Oxalis species, O. phaeotricha and O. picchensis, were inferred to be tetraploid (both with approx. 1·67 pg/2C), the latter being one of the putative progenitors of O. tuberosa identified by chloroplast‐expressed glutamine synthetase data in prior work. The remaining accessions (from 78 populations provisionally identified as 35 species) were DNA diploid, with nuclear DNA contents varying from 0·79 to 1·34 pg/2C.
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The Oxalis tuberosa alliance is a group of morphologically similar Oxalis species allied to the Andean tuber crop oca, O. tuberosa. Originally described by cytologists as a dozen species sharing a base chromosome number rare in Oxalis (x... more
The Oxalis tuberosa alliance is a group of morphologically similar Oxalis species allied to the Andean tuber crop oca, O. tuberosa. Originally described by cytologists as a dozen species sharing a base chromosome number rare in Oxalis (x = 8), the alliance as defined here includes additional species for which cytological information is not yet available but which are supported as members on molecular and/or morphological grounds. The alliance includes members found in the Andean region from Venezuela to northern Argentina, with one species at high elevations in Central America. They occur from the high Andean steppes (páramo and puna) to the cloud forests of middle elevations and include both restricted endemics and variable widespread species complexes. Geographical and altitudinal distributions of members of the alliance and selected Oxalis species outside the alliance were compared with a combined phylogenetic analysis of DNA sequence data of ITS and ncpGS (chloroplast-expressed glutamine synthetase). Groups within the alliance (i.e., major clades on the molecular trees) occur across widespread, overlapping regions in the Andes, with only partial ecological separation. The hypothesis that the O. tuberosa alliance may have developed in the Andes of southern Peru and northwestern Bolivia and radiated southward and, especially, northward along the Andean axis is suggested by patterns of distributions of members of the alliance and outgroups. In spite of uncertain species delimitations, it is clear that the alliance includes many endemic species and ecotypes that have very restricted distributions. As relatives of the Andean tuber crop Oxalis tuberosa, the genetic diversity represented by this geographical variability should be a high priority for conservation.
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Chloroplast-expressed glutamine synthetase (ncpGS), a nuclear-encoded gene containing several introns, is introduced as a tool for phylogenetic studies at lower taxonomic levels. This gene is a member of a multigene family, but it... more
Chloroplast-expressed glutamine synthetase (ncpGS), a nuclear-encoded gene containing several introns, is introduced as a tool for phylogenetic studies at lower taxonomic levels. This gene is a member of a multigene family, but it diverged long ago from the cytosolic-expressed members of the family and appears to be single copy in the majority of taxa examined to date. The conservation of both coding sequence and position of introns has allowed the design of primers for use in a broad range of dicot taxa to amplify and sequence a region of ncpGS that contains four introns. The utility of this region in phylogenetic studies of congeneric species is illustrated by an example using eight Oxalis species. The four introns in these taxa are typical in size (76 to 136 bp), base composition (high T content), and structure (e.g., sequence of splice sites and putative branch points) for plant internal introns. Levels of variation among these ncpGS sequences compare favorably with those of the internal transcribed spacer of nuclear ribosomal DNA (ITS) from the same taxa, and results of phylogenetic analysis of ncpGS data are generally congruent with previous results using ITS.
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As part of a study aimed at elucidating the origins of the octoploid tuber crop "oca," Oxalis tuberosa, DNA sequences of the internal trancribed spacer of nuclear ribosomal DNA (nrDNA ITS) were determined for oca and several wild Oxalis... more
As part of a study aimed at elucidating the origins of the octoploid tuber crop "oca," Oxalis tuberosa, DNA sequences of the internal trancribed spacer of nuclear ribosomal DNA (nrDNA ITS) were determined for oca and several wild Oxalis species, mostly from Bolivia. Phylogenetic analysis of these data supports a group of these species as being close relatives of oca, in agreement with morphology and cytology, but at odds with traditional infrageneric taxonomy. Variation in ITS sequences within this group is quite low (0-7 substitutions in the entire ITS region), contrasting with the highly divergent (unalignable in some cases) sequences within the genus overall. Some groups of morphologically differentiated species were found to have identical sequences, notably a group that includes oca, wild populations of Oxalis that bear small tubers, and several other clearly distinct species. The presence of a second, minor sequence type in at least some oca accessions suggests a possible contribution from a second genome donor, also from within this same species group. ITS data lack sufficient variation to elucidate the origins of oca precisely, but have identified a pool of candidate species and so can be used as a tool to screen yet unsampled species for possible progenitors.
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The gibberellins (GAs) of both vegetative (leaves and stems) and reproductive (pods and seeds) tissue of the G2 strain of peas Pisum sativum L. were characterized in purified extracts by a combination of sequential silicic-acid partition... more
The gibberellins (GAs) of both vegetative (leaves and stems) and reproductive (pods and seeds) tissue of the G2 strain of peas Pisum sativum L. were characterized in purified extracts by a combination of sequential silicic-acid partition column chromatography, and gas chromatography-mass spectrometry. Gibberellins A19, A20, A29 and an A29 catabolite were identified in both types of tissue. Gibberellins A9, A17 and A44 were also found in pods and seeds.
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One target of the Global Strategy for Plant Conservation involves conserving genetic diversity of crops. In addition, the UN-FAO’s 2nd State of the World’s Plant Genetic Resources for Food and Agriculture (SoWPGRFA) report recommends that... more
One target of the Global Strategy for Plant Conservation involves conserving genetic diversity of crops. In addition, the UN-FAO’s 2nd State of the World’s Plant Genetic Resources for Food and Agriculture (SoWPGRFA) report recommends that more attention be given to “minor crops,” recognizing that even those crops that are not among the most important ones worldwide are nonetheless crucial components of the food systems of particular world regions. The ex-situ conservation of vegetatively-propagated crops faces particular challenges compared to seed-propagated crops that can be maintained as frozen seed. Thus, complementary in-situ conservation strategies are even more needed to maintain local diversity as a vital resource for food security in rural communities.
One goal of the SoWPGRFA report is to “develop better indicators and methodologies to assess conservation status and threats.” Because conservation of crop diversity requires information about how that diversity is distributed geographically, the use of GIS techniques for the study of crop diversity is increasing. However, this does not usually include the use of methods from geographical genetics and spatial statistics. We conducted spatial statistical analyses of the Andean tuber crop “oca” Oxalis tuberosa, as a model to study the evolution of clonally-propagated crops under human influence. Because clonal crops differ from seed-propagated crops in their conservation needs, we used oca as an example to study how human-mediated dispersal affects the genetic structure of clonal crop populations, i.e., how the exchange of planting material among farmers determines the distribution of oca’s clonal genotypes in traditional Andean agriculture.
Cultivated oca was sampled randomly in carefully-distributed localities throughout the Peruvian Andes, and samples were subsequently cultivated in a highland experiment station of INIA (Instituto Nacional de Innovación Agraria) for morphological and molecular analyses. Spatial statistical analyses of AFLP data of 954 oca individuals from 38 localities were done for both individual AFLP alleles and clonal genotypes, the latter determined by both AFLP and morphological data. One finding with important conservation implications is that many oca clonal genotypes have very restricted geographic distributions; some were found in only four or fewer communities. Most of these were restricted to a particular area in Peru, whereas a few others were found in scattered, discontinuous areas. Our initial spatial autocorrelation analyses (Moran’s I and join-count) yielded many very strong but unusual patterns across both spatial scales and genotypes. This indicates that there are other factors besides geographic distance which have shaped the distribution of genotypes, and we continue to investigate what these factors may be.
In addition to the cultigen, wild Oxalis species were also collected, including a wild, tuber-bearing taxon found in highland provinces of Lima Department. The latter taxon was included in continuing research to determine the progenitors of cultivated oca, but the results using AFLP data did not support these populations as likely progenitors of oca (Emshwiller et al. 2009. Amer. J. Botany 96:1839-1848).
One goal of the SoWPGRFA report is to “develop better indicators and methodologies to assess conservation status and threats.” Because conservation of crop diversity requires information about how that diversity is distributed geographically, the use of GIS techniques for the study of crop diversity is increasing. However, this does not usually include the use of methods from geographical genetics and spatial statistics. We conducted spatial statistical analyses of the Andean tuber crop “oca” Oxalis tuberosa, as a model to study the evolution of clonally-propagated crops under human influence. Because clonal crops differ from seed-propagated crops in their conservation needs, we used oca as an example to study how human-mediated dispersal affects the genetic structure of clonal crop populations, i.e., how the exchange of planting material among farmers determines the distribution of oca’s clonal genotypes in traditional Andean agriculture.
Cultivated oca was sampled randomly in carefully-distributed localities throughout the Peruvian Andes, and samples were subsequently cultivated in a highland experiment station of INIA (Instituto Nacional de Innovación Agraria) for morphological and molecular analyses. Spatial statistical analyses of AFLP data of 954 oca individuals from 38 localities were done for both individual AFLP alleles and clonal genotypes, the latter determined by both AFLP and morphological data. One finding with important conservation implications is that many oca clonal genotypes have very restricted geographic distributions; some were found in only four or fewer communities. Most of these were restricted to a particular area in Peru, whereas a few others were found in scattered, discontinuous areas. Our initial spatial autocorrelation analyses (Moran’s I and join-count) yielded many very strong but unusual patterns across both spatial scales and genotypes. This indicates that there are other factors besides geographic distance which have shaped the distribution of genotypes, and we continue to investigate what these factors may be.
In addition to the cultigen, wild Oxalis species were also collected, including a wild, tuber-bearing taxon found in highland provinces of Lima Department. The latter taxon was included in continuing research to determine the progenitors of cultivated oca, but the results using AFLP data did not support these populations as likely progenitors of oca (Emshwiller et al. 2009. Amer. J. Botany 96:1839-1848).
Although ethnobotany is a multidisciplinary field by definition, most ethnobotanical studies are centered primarily in either the social sciences or the natural sciences, and few studies integrate between these domains. Yet when we draw... more
Although ethnobotany is a multidisciplinary field by definition, most ethnobotanical studies are centered primarily in either the social sciences or the natural sciences, and few studies integrate between these domains. Yet when we draw on data and methods from across disciplinary boundaries in studies of the evolution and conservation biology of crop plants, we may uncover information that would have remained hidden if the studies were conducted within a single discipline. Both studies of crop origins and studies of ongoing crop evolution can integrate anthropological survey data with molecular data. Our studies of the Andean tuber crop “oca,” Oxalis tuberosa, have addressed both the crop’s origins (of polyploidy and domestication) and its continuing evolution, and have integrated data from surveys of farmers with molecular, morphological, and DNA ploidy data. Hypotheses derived from survey data were tested with other data sources, leading to new insights that would probably not have been revealed otherwise.
To conserve crop genetic diversity, we need to know what is happening to that diversity through space and time. Because humans are primary dispersal agents for clonally-propagated crops, investigators have used surveys to study “seed flows” of Andean tubers to determine the directions and amounts of “seed tubers” exchanged and transported among farmers. We are now investigating the effects of those exchange networks on the geographic distributions of oca’s clonal genotypes as identified by AFLP and morphological data. New results of spatial-statistical analyses will be presented at the symposium.
To conserve crop genetic diversity, we need to know what is happening to that diversity through space and time. Because humans are primary dispersal agents for clonally-propagated crops, investigators have used surveys to study “seed flows” of Andean tubers to determine the directions and amounts of “seed tubers” exchanged and transported among farmers. We are now investigating the effects of those exchange networks on the geographic distributions of oca’s clonal genotypes as identified by AFLP and morphological data. New results of spatial-statistical analyses will be presented at the symposium.