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The Potato Introduction Station in Sturgeon Bay Wisconsin has maintained herbarium specimens as part of its operations. These specimens mostly were grown from seeds in the field plots or greenhouses, but also include original specimens made during germplasm collecting expeditions. The herbarium of the Station (herbarium acronym PTIS) has been transferred from the potato genebank in Sturgeon Bay Wisconsin to the Wisconsin State Herbarium (acronym WIS) in Birge Hall, University of Wisconsin-Madison where it is now fully integrated and curated and funded by WIS; PTIS is discontinued and is no longer maintained as a separate herbarium. Separately, maps and taxonomic literature that were used by the potato taxonomist in Madison were transferred to the Potato Station in Sturgeon Bay.

Crop wild relatives, the wild progenitors and closely related cousins of cultivated plant species, are sources of valuable genetic resources for crop improvement. Persisting gaps in knowledge of taxonomy, distributions, and characterization for traits of interest constrain their expanded use in plant breeding and likewise negatively affect ex situ (in genebanks) and in situ (in natural habitats) conservation planning. We compile the state of knowledge on the taxonomy and distributions of the wild relatives of carrot (genus DaucusL.) natively occurring within Tunisia—a hotspot of diversity of the genus, containing 13 taxa (27% of species worldwide). We use ecogeographic information to characterize their potential adaptations to abiotic stresses of interest in crop breeding and assess their ex situ and in situ conservation status. We find substantial ecogeographic variation both across taxa and between populations within taxa, with regard to adaptation to high temperatures, low precipitation, and other traits of potential interest. We categorize three of the taxa high priority for further conservation both ex situ and in situ, five medium priority, and five low priority, with none currently considered sufficiently conserved. Geographic hotspots for species diversity, especially in the northern coastal areas, represent particularly high value regions for efficient further collecting for ex situ conservation and for in situ protection in Tunisia.

Plant scientists make inferences and predictions from phylogenetic trees to solve scientific problems. Crop losses due to disease damage is an important problem that many plant breeders would like to solve, so the ability to predict traits like disease resistance from phylogenetic trees derived from diverse germplasm would be a significant approach to facilitate cultivar improvement. Alternaria leaf blight (ALB) is among the most devastating diseases of carrots (Daucusspp., Apiaceae) worldwide. Thus, new approaches to identify resistant germplasm to this disease are needed. In a study of 106 accessions of wild and cultivated Daucusand related genera, we determined plant height is the best explanatory variable to predict ALB resistance using a phylogenetic linear regression model. Using the estimated area under the disease progress curve, the most resistant species to ALB were the non‐carrot relative Ammi visnaga(L.) Lam. and the wild carrot relative D. crinitusDesf. A permutation tail probability test was conducted considering phylogenetic signal to evaluate the strength of association between the Daucusphylogeny and ALB resistance. We found that species belonging to clade A, which includes carrots and other Daucuspossessing 2n= 18, 20, or 22 chromosomes, are slightly more resistant to ALB than members of other clades of the Daucusphylogeny.

The third most important food crop worldwide, potato (Solanum tuberosumL.) is a tetraploid outcrossing species propagated from tubers. Breeders have long been challenged by polyploidy, heterozygosity, and asexual reproduction. It has been assumed that tetraploidy is essential for high yield, that the creation of inbred potato is not feasible, and that propagation by seed tubers is ideal. In this paper, we question those assumptions and propose to convert potato into a diploid inbred line–based crop propagated by true seed. Although a conversion of this magnitude is unprecedented, the possible genetic gains from a breeding system based on inbred lines and the seed production benefits from a sexual propagation system are too large to ignore. We call on leaders of public and private organizations to come together to explore the feasibility of this radical and exciting new strategy in potato breeding.

We report a high-quality chromosome-scale assembly and analysis of the carrot (Daucus carota) genome, the first sequenced genome to include a comparative evolutionary analysis among members of the euasterid II clade. We characterized two new polyploidization events, both occurring after the divergence of carrot from members of the Asterales order, clarifying the evolutionary scenario before and after radiation of the two main asterid clades. Large- and small-scale lineage-specific duplications have contributed to the expansion of gene families, including those with roles in flowering time, defense response, flavor, and pigment accumulation. We identified a candidate gene, DCAR_032551, that conditions carotenoid accumulation (Y) in carrot taproot and is coexpressed with several isoprenoid biosynthetic genes. The primary mechanism regulating carotenoid accumulation in carrot taproot is not at the biosynthetic level. We hypothesize that DCAR_032551 regulates upstream photosystem development and functional processes, including photomorphogenesis and root de-etiolation.

With ca. 200 species, the informally named Potato clade represents one of the larger subgroups of the estimated 1500 species of Solanum. Because its members include the potato (S. tuberosum), tomato (S. lycopersicum), and pepino (S. muricatum), it is the most economically important clade in the genus. These crop species and their close relatives have been the focus of intensive research, but relationships among major lineages of the Potato clade remain poorly understood. In this study, we use sequences from the nuclear ITS and waxy(GBSSI), and plastid trnT-trnFand trnS-trnGto estimate a phylogeny and further explore relationships within the Potato clade. With increased sampling over past studies, the Potato clade emerges as a strongly supported clade and comprises 12–13 subclades which, for the most part, correspond to traditionally recognized sections. Solanumsect. Regmandrais sister to the rest of the lineages of the Potato clade which are, in turn, organized into two major subclades: (1) sections Anarrhichomenum, Articulatum, Basarthrum, Etuberosum, Juglandifolia, Lycopersicoides, Lycopersicon, and Petota, and (2) sections Herpystichumand Pteroidea. As in all other studies including these groups, sections Etuberosum, Juglandifolia, Lycopersicoides, Lycopersicon, and Petotaform a strongly supported clade. Solanum oxycoccoides, a high-elevation species endemic to north-central Peru, was tentatively assigned to several groups within Solanumbased on morphological evidence, but instead the species represents an independent lineage within the Potato clade, sister to the first major subclade. A key to the sections of the Potato clade is provided.

The genus Daucusincludes about 20 recognized species. The most widespread and economically important species, Daucus carotaL., occurs on almost every continent. The cultivated carrot, subsp. sativus(Hoffm.) Schübl. and G. Martens, has been selected from wild populations that are extremely diverse, especially in the western Mediterranean. The predominant outcrossing and the lack of sexual isolating mechanisms among recognized infraspecific taxa complicate the taxonomy and identification of the wild populations, resulting in widely different interpretations of the number of infraspecific taxa. We measured 36 morphological characters from multiple individuals within each of 155 accessions of D. carotaand from the morphologically similar species D. capillifolius(both species 2n= 18) alongside other species for comparison (D. aureusDesf., 2n= 22; D. broteriTen., 2n= 20; D. involucratusSm., 2n= 20; and D. littoralisSm., 2n= 20) in an experimental field plot. Within D. carota, multivariate analyses were able to identify only two subspecies, but even these showed great overlap of individual characters. Because of the ease of crossability of wild D. carotato the domestic landraces and cultivars and because of the taxonomic challenges, the purpose of our study is to explore morphological support for subspecies within D. carota, including the phenetically similar D. capillifolius, which is part of the same clade as D. carota, with the long‐term goal of resolving taxonomic disagreements and developing a practical system to classify variation within this economically important species.

Taxonomic complexity in wild potatoes (SolanumL. sect. PetotaDumort.) has led to widely conflicting treatments. Solanumser. PiuranaHawkes is one of 21 series recognized in S. sect. Petotain the latest comprehensive taxonomic treatment by Hawkes in 1990. They are distributed from southern Colombia south through Ecuador to central Peru. The taxonomic limits of the series and validity of its constituent species were not resolved with previous studies. In the present study, a set of five conserved orthologous DNA markers (cos II) with 5342 bp of aligned length were used to infer the phylogeny of putative members of Solanumser. Piuranaand outgroups. The results agreed with a three-clade topology shown by previous studies within S. sect. Petota. Solanumser. Piuranais expanded to include some species formerly included in S. sers. Conicibaccata, Cuneoalata, Ingaefolia, Olmosiana, Simplicissima, Tuberosaand Yungasensa. This expanded group is supported morphologically by the presence of moniliform tubers and coriaceous leaves in most species.

A major justification for taxonomic and biogeographic research is its assumed ability to predict the presence of traits in a group for which the trait has been observed in only a representative subset of the group. Such predictors are regularly used by breeders interested in choosing potential sources of disease and pest resistant germplasm for cultivar improvement, by genebank managers to organize the collection, and by germplasm collectors planning to gather maximum diversity. The present study tests taxonomic and biogeographic associations with 10,738 disease and pest evaluations, derived from the literature and genebank records, of 32 pest and diseases in five classes of organisms (bacteria, fungi, insects, nematodes, and virus). The data show that ratings for only Colorado potato beetle [Leptinotarsa decemlineata(Say)] and one pathogen (Potato M Carlavirus) are reliably predicted both by host taxonomy and climatic variables. While it is logical to initially take both taxonomy and geographic origin into account while screening genebank materials for pest and disease resistances, such associations will hold for only for a small subset of resistance traits. Based on these results, a more effective strategy than taxonomic and biogeographic prediction is probably careful screening of core collections.

There are a number of effective treatments for breast cancer in the neo-adjuvant, adjuvant and metastatic setting. These comprise combinations of radiotherapy, chemotherapy, hormonal treatments and targeted molecular therapies. However the benefit that individual patients derive from these treatments and the toxicity that they experience varies considerably. Differences in cancer patient's responses to therapy can be associated with factors such as disease burden, drug interactions, age, gender and nutritional status amongst others. It is now also known that genetic variations in drug target genes, disease pathway genes and drug metabolizing enzymes can have important role and influence on the efficacy and toxicity of a particular therapy. These genetic variations may be due to variations in individual's germ line DNA or to somatic changes in the malignant cells. Understanding the genetic profile of the patient and the tumour will help to further refine therapies. Pharmacogenomics can be used to predict response to treatments that are known to have activity against breast cancer including anthracyclines, cyclophosphamide, methotrexate, fluorouracil, taxanes, tamoxifen, aromatase inhibitors and herceptin. The reliability and reproducibility of techniques needs to be validated in large randomized studies before they can be incorporated into routine clinical practice. Thus pharmacogenomics will help develop a profile to tailor therapies with minimal toxicity and maximum efficacy based on molecular signatures. This review discusses clinically relevant germ line mutations that can be used to predict response and toxicity to the above treatments as well as microarray based expression profile studies that may yield important information about prognosis, indication for treatment and response to treatment. The completion of the human genome project and advances in high through-put DNA sequencing and proteomic technology means that there is a real opportunity for pharmacogenomic assessment to become a clinically important part of the decision making process in determining the optimum adjuvant treatment regimen for patients with early stage breast cancer and aiding the management of advanced breast cancer, allowing clinicians to create an individual management plan for each breast cancer patient based on pharmacogenomic data.

Solanum berthaultiiand S. tarijenseare two wild potato (sect. Petota) species distributed from Bolivia to northern Argentina. All authors have accepted them as good species since their publication in 1944, but they have been hypothesized to hybridize extensively with each other and with other species, despite their classification into different series and superseries by some authors. This study is a molecular counterpart (AFLPs, plastid DNA restriction site data, survey of a plastid DNA deletion) to a prior morphological study of these two species. AFLP data show weak support for separate species status for some accessions, but with many exceptions. In agreement with the morphological results we place S. tarijenseinto synonymy of S. berthaultii, and use herbarium specimen data for a taxonomic treatment to include a description, synonymy, and mapping of all accessions. We show similar taxonomic problems in sect. Petotaand suggest that there will be a continuing trend of reduction of names in wild potatoes.

The modern cultivated potato (Solanum tuberosumL.) was first recorded in Europe in the Canary Islands in 1567, but its origin has long been in dispute. Two competing hypotheses have proposed an “Andean” area (somewhere from the Andean uplands from Venezuela to northern Argentina) or a lowland south‐central “Chilean” area, but the Andean origin hypothesis is today generally accepted. The identity of extant Canary Island potato landraces as exclusively of upland Andean origin is one part of a multicomponent argument that the European potato originated from there, rather than from Chile. We reassess these two competing hypotheses with nuclear microsatellite and chloroplast DNA analyses of 19 Canary Island landraces, 14 Andean landraces, 11 Chilean landraces, and two wild potato species as outgroups, and with chloroplast DNA data of 150 landraces from South America. Our molecular results document a wide variation of Andeanߚ and Chilean‐type cultivars on the Canary Islands and possible hybrids of the two. Our new data, integrated with historical, molecular, agronomic, and crossing data, support a hypothesis that there were multiple introductions of Andean and Chilean germplasm to the Canary Islands and that the early European potato was selected from Chilean introductions long before the late blight epiphytotics of the 1840s.

A major justification for taxonomic research is its assumed ability to predict the presence of traits in a group for which the trait has been observed in a representative subset of the group. Taxonomy is regularly used by breeders interested in choosing potential sources of disease‐resistant germplasm for cultivar improvement. We designed this study as an empirical test of prediction by associating resistance to white mold [caused by the fungal pathogen Sclerotinia sclerotiorum(Lib.) de Bary] to diverse potato (Solanumspp.) taxonomies and biogeography, using 144 accessions of 34 wild relatives of potato in Solanumsections Petotaand EtuberosumTremendous variation for resistance to white mold occurs both within and among species. No consistent association was observed between white mold resistance and taxonomic series (based on a phenetic concept), clades (based on a cladistic concept), ploidy, breeding system, geographic distance, or climate parameters. Species and individual accessions with high proportions of white‐mold‐resistant plants have been identified in this study, but both often exhibit extensive variation and designation of either as resistant or susceptible must take this variation into account. Therefore, taxonomic relationships and ecogeographic data cannot be reliably used to predict where additional sources of white mold resistance genes will be found.

The article discusses the need to design the campus according to the demands of students belonging to the millennial generation in the U.S. The popularity of distance learning and course casting has spurred changes in the learning environment. A 2004 survey by the University of Georgia cited students' preference to have the in-campus wireless network enhanced and expanded. Another survey at the University of California indicates that people identify natural elements as major campus attraction.

Breast cancer represents a major health problem, with more than a million new cases and 370,000 deaths worldwide yearly. Options and understanding of how to use cytotoxic chemotherapy in both advanced and early stage breast cancer have made substantial progress in the past 10 years, with numerous landmark studies identifying clear survival benefits for newer approaches. Despite this research, the optimal approach for any individual patient cannot be determined from a literature review or decision-making algorithm alone. Treatment choices are still predominantly based on practice determined by individual or collective experience and the historic development of treatment within a locality. In many situations treatment decisions cannot be divorced from economic considerations. Blanket application of international, national or local guidelines is usually impractical or inappropriate and careful consideration of the detailed circumstances of each patient is required to make optimal use of available options. Recent research has allowed us to refine breast cancers further into prognostic groups based on a gene expression profile. Clinical trials to prove the value of this approach are currently being designed. This review discusses the evidence for various chemotherapy regimens in the adjuvant and metastatic settings, and examines the current evidence for the timing of radiotherapy in the adjuvant setting.

Wild tomatoes (Solanumsection Lycopersicon) are native to western South America. The delimitation and relationships of tomato species have differed widely depending upon whether morphological or biological species concepts are considered more important. Molecular data from mitochondrial, nuclear, and chloroplast DNA restriction fragment length polymorphisms (RFLPs), nuclear microsatellites, isozymes, and gene sequences of internal transcribed spacers of nuclear ribosomal DNA (ITS; multiple­copy), the single­copy nuclear encoded Granule­bound Starch Synthase gene (GBSSI or waxy), and morphology, have been used to examine hypotheses of species relationships. This study is a companion to the previous GBSSI gene sequence study and to the morphological study of relationships of all ten wild tomato species (including the recently described S. galapagense), with a concentration on the most widespread and variable species S. peruvianums. l. These new AFLP data are largely concordant with the GBSSI and morphological data and in general support the species outlined in the latest treatment by C. M. Rick, but demonstrate the distinct nature of northern and southern Peruvian populations of S. peruvianum, and suggest that their taxonomy needs revision. Solanum ochranthumis supported as sister to wild tomatoes, and S. habrochaitesand S. pennelliireside in a basal polytomy in the tomato clade.

Recent progress in understanding the phylogeny of the economically important plant family Solanaceae makes this an ideal time to develop models for linking the new data on plant genomics with the huge diversity of naturally occurring species in the family. Phylogenetics provides the framework with which to investigate these linkages but, critically, good species-level descriptive resources for the Solanaceae community are currently missing. Phylogeny in the family as a whole is briefly reviewed, and the new NSF Planetary Biodiversity Inventories project ‘PBI: Solanum—a worldwide treatment’ is described. The aims of this project are to provide species-level information across the global scope of the genus Solanum and to make this available over the Internet. The project is in its infancy, but will make available nomenclatural information, descriptions, keys and illustrative material for all of the approximately 1500 species of Solanum. With this project, the opportunity of linking valid, up-to-date taxonomic information about wild species of Solanum with the genomic information being generated about the economically important species of the genus (potato, tomato and eggplant) can be realized. The phylogenetic framework in which the PBI project is set is also of enormous potential benefit to other workers on Solanum. The community of biologists working with Solanaceae has a unique opportunity to effectively link genomics and taxonomy for better understanding of this important family, taking plant biology to a new level for the next century. Copyright © 2004 John Wiley & Sons, Ltd.

This study tests the genetic difference between landrace populations of Solanum tuberosumL. subsp. tuberosumand subsp. andigenum(Juz. & Bukasov) Hawkes using nuclear DNA microsatellites. Microsatellite loci were amplified in subsp. andigenum(35 accessions), subsp. tuberosum(35 accessions), and other cultivated and wild species (22 accessions). A total of 208 alleles were scored from 18 microsatellite loci spread throughout all 12 chromosomes of potato. Using an infinite allele model and a least squares method of analysis, microsatellite loci separated subsp. tuberosumfrom subsp. andigenum, and cultivated and wild species. These results support the genetic difference of these two populations and their recognition at some classification level.

This paper reviews the systematics of wild potatoes over the past 11 years, in reference to the latest comprehensive taxonomic treatment by Hawkes (1990. The potato: evolution, biodiversity and genetic resources. Belhaven Press, Washington, D.C.). Included here is information on monographs and floras, new germplasm collections made since 1988 compared to total potato distributional data, new taxonomic changes (including synonymy and new species descriptions), ingroup and outgroup relationships, intraspecific studies, diversity studies, and fingerprinting. In addition, data supporting taxonomic changes and phylogeny from ploidy levels, Endosperm Balance Numbers, and morphological studies of taxonomically important characters are reviewed. A revised list of 206 species is presented (from 232 in Hawkes) that incorporates recent synonymy of names, recognition of new names, and new species descriptions. New germplasm collections of 58 potato taxa were collected that did not occur in genebanks before 1988.

Peru contains about half of the described wild potato taxa, and many of these are not yet preserved in genebanks. This paper reports results of the second of a series of five planned collecting expeditions to Peru. Collections were made in the central Peruvian departments of Ancash, Huancavelica, La Libertad, and Lima, from March 8 to April 25,1999. They follow collections in 1998 in the southern Peruvian departments of Apurimac, Arequipa, Cusco, Moquegua, Puno, and Tacna. We collected 101 germplasm accessions, including first germplasm collections of the following 22Solanumtaxa:Solanum amayanum, S. anamatophilum, S. arahuayum(lost in germplasm increase),S. augustii, S. bill- hookeri, S. cantense, S. chavinense, S. chomatophilum var. subnivale, S. chrysoflorum, S. gracilifrons, S. hapalos um, S. huarochiriense, S. hypacrarthrum, S.jalcae, S. moniliforme, S. multiinterruptum f. longipilosum, S. multiinterruptum var. machaytambinum, S. peloquinianum, S. rhombilanceolatum, S. simplicissimum, S. taulisense(lost in germplasm increase), andS. wittmackii. In addition, new collections were made of the under-collected speciesS. hastiforme(three collections). The above taxonomy is that used in planning our expedition, that we compare to a new treatment of Peruvian wild potatoes published by C. Ochoa in 1999. This paper reports the collection and new species identifications of the 1999 collections, and germplasm conservation and survival of the 1998 and 1999 collections. In addition, chromosome counts are provided for 134 accessions from the 1998 and 1999 expeditions, including first reports forS. chomatophilum var. subnivale(2n = 2x = 24),S. megistacrolobumsubsp.purpureum(2n = 2x = 24), andS. multiinterruptumvar.multiinterruptumf.albiflorum(2n = 2x = 24); we also report the first triploid count of an accession ofS. immite.

Prior to 1996, worldwide holdings of germplasm of wild potatoes from Costa Rica amounted to just two collections; this country therefore formed a priority for collecting. We mapped all localities of wild potatoes from herbarium specimen data from Costa Rica and collected throughout the country. We made 13 collections, 10 of these with botanical seeds. These collections considerably extend the numbers of accessions and geographic range of the germplasm available from Costa Rica. The taxonomic identity of the species of wild potatoes (Solanumsect. Petota) in Costa Rica was previously unresolved. Our fieldwork supports the concept that Costa Rican wild potatoes belong to a single species,S. longiconicum.

Wild potato (Solanumsect.Petota)germplasm has been collected in Mexico on nine major expeditions, as determined by 20 collections or more from each expedition currently at the United States potato genebank, the National Research Support Program-6 (NRSP-6). These have resulted in 609 accessions with good collection data. In addition, NRSP-6 has germplasm of approximately 90 other Mexican collections that are unspecific regarding date or place of collection. This expedition was funded to collect those remaining collections with no or little germplasm:Solanum clarum,S.xedinense, S. hintonii, S. hjertingiivar.physaloides, S. leptosepalum, S. lesteri, S. macropilosum, S.xmichoacanum, S.xsambucinum, andS. stenophyllidium. In addition, some species and species groups (species groups indicated in parentheses) have unresolved taxonomic problems that needed clarification by additional field collections. These are (S. agrimonifoliumand S.oxycarpum), (S. brachycarpum, S. guerreroense, S. hougasii, andS. iopetalum- theS. brachycarpumcomplex), (S. fendleri, S. papita, S. stoloniferum- theS. stoloniferumcomplex),S. leptosepalum, andS. macropilosum. We conducted a wild potato germplasm collecting expedition in Mexico from August 22 to October 31, 1997. Our 103 collections, 71 as germplasm collections, provide the first germplasm samples forS. hjertingiivar.physaloides,S. leptosepalum, andS. macropilosum. They provide additional germplasm of the rare speciesS. clarum, S.xedinense, S. lesteri, S.xmichoacanum, S.xsambucinum, andS. stenophyllidium. We additionally gathered germplasm and field data to help resolve taxonomic difficulties inS. agrimonifoliumandS. oxycarpum, theS. brachycarpumcomplex, and theS. stoloniferumcomplex.

Peru has 103 taxa of wild potatoes (species, subspecies, varieties, and forms) according to Hawkes (1990; modified by us by a reduction of species in theSolanum brevicaulecomplex) and including taxa described by C. Ochoa since 1989. Sixty-nine of these 103 taxa (67% ) were unavailable from any of the world’s genebanks and 85 of them (83%) had less than three germplasm accessions. We conducted a collaborative Peru (INIA), United States (NRSP-6), and International Potato Center (CIP) wild potato (Solanumsect.Petota)collecting expedition in Peru to collect germplasm and gather taxonomic data. This is the first of a series of planned expeditions from 1998–2002. We collected from February 18 to April 18, 1998, in the southern departments of Apurímac, Arequipa, Cusco, Moquegua, Puno, and Tacna. We made 57 germplasm collections, including 14 taxa that are the first available as germplasm for any country (Solanum aymaraesense, S. chillonanum, S. incasicum, S. megistacrolobumsubsp.megistacrolobum f. purpureum, S. longiusculus, S. multiflorum,S. pillahuatense, S. sawyeri, S. sandemanii, S. tacnaense, S. tarapatanum, S. urubambae, S. velardei, S. villuspetalum), and two additional taxa that are the first available for Peru but with germplasm from Bolivia (S. megistacrolobumsubsp.toralapanum, S. yungasense).Collections also were made for the rare taxaS. acroscopicum, S. buesii, S. limbaniense, andS. santolallae.Our collections suggest the following minimum synonymy may be needed for Peruvian potatoes:S. sawyerias a synonym ofS. tuberosum;S. hawkesiiandS. incasicumas synonyms ofS. raphanifolium;S. multiflorumandS. villuspetalumas synonyms ofS. urubambae.

TheSolanum brevicaule complex is a group of morphologically very similar wild and cultivated potato taxa (Solanum sect.Petota). This study uses single to low-copy nuclear RFLPs and RAPDs to investigate their species boundaries and relationships. Cladistic analyses of both data sets are largely concordant with each other and with a recently published phenetic analyses of the same accessions using morphology. All three data sets separate members of the complex into populations from Peru and immediately adjacent northwestern Bolivia, including most cultivated species accessions, and populations from northwestern Bolivia to Argentina. The molecular results suggest that the complex is paraphyletic as currently circumscribed. Many species of theS. brevicaule complex should be relegated to synonymy.

Abstract: A joint Danish, Mexican, United States wild potato (Solanum sect.Petota) germplasm collecting expedition was conducted in Mexico between Aug. 21-Oct. 20, 1988. The trip resulted in 93 seed and 25 tuber collections of 18 species and one putative natural hybrid,S. xmichoacanum. Rare species collected include:Solanum darum,S. hintonii,S. lesteri, andS. xmichoacanum. First germplasm collections were made of the disjunct populations ofS. fendleri from Baja California. The potential and realized breeding value of these species is discussed.

Solanum L. sect. Petota Dumort., the potato and its wild relatives, contains 232 species, according to the latest taxonomic interpretation of Hawkes (1990). Section Petota is distributed in the Americas from the southwestern United States to southern Chile. This economically important group has attracted the attention of numerous taxonomists with various taxonomic philosophies. There are 531 validly published basionyms in the group, plus 67 nomina nuda or nomina dubia, and subsequent transfers to other ranks raise the number of names to 664. The taxonomy of sect. Petota has been dominated in recent years by J. G. Hawkes & J. P. Hjerting (co-workers) and C. M. Ochoa. The near simultaneous and independent publication of three recent books by these workers, treating the Bolivian species of sect. Petota, provides a novel opportunity to compare their taxonomic philosophies. Additionally, a recent independent treatment of all of the South American species by L. E. Gorbatenko provides a new interpretation of affiliations of species to series that is compared to the recent treatment of Hawkes and earlier treatments of S. M. Bukasov and D. S. Correll. These treatments differ in the placement of species into series, species boundaries, rank of infraspecific taxa, and hypotheses of hybridization. Our analysis illustrates the wide differences of taxonomic interpretation possible when independent workers treat the same material. The comparison provides insights into unresolved taxonomic questions in sect. Petota and indicates the need for a practical taxonomic resolution that will benefit plant breeders and other researchers on wild potatoes. Reasons for the discrepancies are discussed and suggestions for future research are provided.

Current taxonomic interpretations ofSolanum microdontumBitter partition the species into two or three infraspecific taxa, variously recognized as subspecies or varieties. The present study reexamines these taxa using morphological data from four individuals each of 69 accessions from most of the range of the species, planted in a common field plot. Our results show that the character states used to recognize infraspecific taxa inS. microdontum often vary within accessions and have no correlation with geography. We conclude that past hypotheses have used typological concepts and that infraspecific taxa are not warranted. This study questions other hypotheses of infraspecific taxa in sect.Petota.

Engineering modeling and design generally involve a large set of independent but interrelated data items. One way to organize and store these data items in a systematic and consistent manner is through the use of a database management system. The abstraction concepts of aggregation and generalization provide a powerful mechanism for organizing and structuring engineering data. The invariants required to maintain the abstract data model are examined in this paper. Integrity issues involved in the data representation of hierarchically structured engineering models, such as constructive solid geometry models, are discussed. Object-oriented programming concepts are used to implement a prototype integrity subsystem for enforcement of integrity constraints in the aggregation/generalization framework for modeling data.

Bamberg, J. B. & Spooner, D. M.: The United States Potato Introduction Station Herbarium. – Taxon 43:489‐496. 1994. – ISSN 0040‐0262. The United States Potato Introduction Station Herbarium at Sturgeon Bay, Wisconsin, serves the National Research Support Program‐6 (NRSP‐6; formerly known as the Inter‐Regional Potato Introduction Project IR‐1). NRSP‐6 is part of the United States germplasm system and is the sole genebank for wild and cultivated potatoes in the United States. The genebank and herbarium are devoted entirely to wild and cultivated potatoes (Solanumsect. Petota). NRSP‐6 is charged with the introduction, preservation, classification, evaluation, and distribution of potato germplasm worldwide. Recent expeditions and grants for upgrading the herbarium and associated facilities have provided a valuable new international resource for researchers in S.sect. Petota.

Many morphological features of the heads of Compositae are systematically useful. Receptacular bracts (pales or paleae) are of particular significance taxonomically. These structures occur in nine of the 13 recognized tribes (absent in Arctoteae, Calenduleae, Senecioneae and Tageteae), with the greatest concentration in the Anthemideae, Heliantheae, and Inuleae. Because the Heliantheae contain the broadest diversity of pale types, the adaptive significance of these features within this tribe deserves special emphasis. Certain subtribes of the Heliantheae are characterized by distinctive types of pales, such as flattened with orange‐brown lines in the Coreopsidinae, pales subtending only the outer series of disc florets in the Madiinae, or their complete absence in the Bahiinae. Of the five principal factors affecting the evolution of features of heads in the family, viz., protection, dispersal, pollination, breeding systems, and seed germination, the former two are most likely the most important selective forces in the evolution of pales. Dispersal functions of pales include attachment or close envelopment of the achene by the pales with removal of the entire unit by wind from the head, conduplicate pales serving as chutes for release of unattached achenes, and brightly colored, fleshy pales being attractive to animals. Protective functions occur against predators and environmental extremes, and occur in bud, anthesis, and mature fruiting stages. Pales function during anthesis to protect ovaries and achenes from apical and lateral insect attack. The particular variations of the pales depend on the associated structures of the heads and breeding systems. In a phylogenetic context, the large and sometimes foliose pales of the Heliantheae seem best interpreted as adaptations for protection of large achenes and not necessarily as reflections of a primitive condition within the family.

Enzyme electrophoresis was employed to measure genetic variation within and divergence among 32 populations of three species in Solanumsect. Petota(S. brevidens, S. etuberosum, and S. fernandezianum). These species are self‐compatible, diploid (2n = 2x =24), and members of the monophyletic series Etuberosa. Solanum etuberosumis distributed in southern Chile, S. brevidensoccurs in southern Chile and adjacent southern Argentina, and S. fernandezianumis endemic to Masatierra Island in the Juan Fernández Archipelago, 650 km west of continental Chile. Very low levels of observed heterozygosity (0.00–0.04) are found within populations of all three species. Interspecific mean genetic identities between S. brevidensand S. etuberosum(0.854) were similar to their intraspecific values (0.923, 0.865, respectively), with both species monomorphic for alleles at nine of the 12 loci examined. Solanum fernandezianumshows no heterozygosity and is more divergent to both S. brevidens(0.780) and S. etuberosum(0.698) than either is to each other. The divergence of S. fernandezianumto S. brevidensand S. etuberosumresults from novel alleles at two of the 12 isozyme loci; in addition, it possesses only a subset of the variability found in S. brevidensand S. etuberosumat three other loci.

Chloroplast DNA restriction site analysis has been used to test Hawkes's phylogenetic interpretations of the genomic data in Solanumsect. Petota.Hawkes hypothesized a diploid (2n= 24) origin of the tuber‐bearing members of this group (subsection Potatoe) in Mexico and Central America (as a B genome) with later migrations and evolution to an A genome in South America, later followed by a return migration of the A genome to Mexico and Central America with A × B hybridizations and polyploidizations to produce ser. Longipedicellata(4x) and Demissa(6x). Our results provide partial support for this hypothesis by demonstrating the paraphyletic and primitive nature of the B genome species group, and the monophyletic and derived nature of all A genome and A × B genome species, including S. verrucosum, a hypothesized A genome progenitor of ser. Demissa.Thus, the Mexican and Central American polyploid species must have obtained their cytoplasm from the A genome. However, our results question the Stellata/Rotata hypothesis of Hawkes and the taxonomic placement of S. chomatophilumin ser. Conicibaccata.

Nepal is rich in indigenous wild and landrace plant genetic resources for agronomic, horticultural, forestry, or medicinal uses, but much of this germplasm remains uncollected and awaits economic development. We list 485 entries (species, or genera for ornamental plants) in 14 categories, and compare these to existing germplasm collections in Nepal and the United States to highlight collection and conservation needs. To help plant plant collecting, we outline the key botanical and logistical data and legal framework for planning field work in Nepal.

We conducted a joint Colombia/United States/Venezuela wild potato (Solanum sect. Petota Dumort.) germplasm collecting expedition in Colombia from June 27–August 24, and in Venezuela from August 17–September 15, 1992. The goals of the expedition were to collect germplasm and study the species boundaries of all of the 23 Colombian and Venezuelan taxa accepted by current taxonomists. We made 128 collections of 16 of these taxa, 96 as true seed collections. We collected the first available germplasm collections of S. cacetanum, S. cuatrecasasii, S. estradae, S. lobbianum, S. orocense, S. paramoense, and S. sucubunense, and obtained germplasm collections of S. neovalenzuelae and S. pamplonense as a germplasm exchange from the Colombian national germplasm collection. We had problems identifying some of our collections, and currently are investigating them for species status and interrelationships. We summarize the state of germplasm collections for Colombia and Venezuela, provide our field data regarding the taxonomy of Colombian and Venezuelan wild potatoes, and provide recommendations for future collecting.

We conducted a joint Ecuador/Colombia/United States wild potato (Solanum sect. Petota) germplasm collecting expedition in Ecuador from April 13–July 1, 1991. The goals of the expedition were to collect germplasm and study the species boundaries of all of the 25 Ecuadorian taxa accepted by current taxonomists. We made 126 collections of 24 of these 25 taxa, 113 as germplasm samples, 13 only as herbarium collections. We synonymize six of these 25 names (S. baezense Ochoa, S. cyanophyllum Correll, S. pichinchense Bitter & Sodiro, S. serratoris Ochoa, S. suffrutescens Correll as synonyms of S. andreanum Baker; S. correllii Ochoa as a synonym of S. regularifolium Correll). Four other names (S. chomatophilum f. angustifoliolum Correll, S. moscopanum Hawkes, S. solisii Hawkes, S. tundalomense Ochoa) could not be consistently distinguished from S. colombianum Dunal in the field. We are currently investigating them to determine their species status.

A product database for a design and manufacturing enterprise serves as a repository for the data needed to manufacture a product. This paper discusses how an object-oriented persistent object manager named ROSE, under development at Rensselaer, has been used in the Rensselaer CIM program to develop a STEP/PDES-compliant product database for its research test bed. In so doing, it provides an overview of the requirements for a product database system in an integrated design and manufacturing facility, and it discusses how the chosen system meets these requirements.

A joint Chilean, United States potato (Solanumsect.Petota) germplasm collecting expedition was conducted in Chile between January 21–March 30, 1989. The trip resulted in collections ofSolanum brevidens(50 accessions),S. etuberosum(28 accessions),S. maglia(3 accessions) and indigenous primitive landraces ofS. tuberosum(24 accessions). Comments are presented on the habitats, distribution, and potential and realized breeding value of these species.

Abstract: The major potato of commerce,Solanum tuberosum L., is the fourth most important food crop in the world after rice, wheat and corn. Fortunately, the potato has many primitive cultivars and wild species relatives useful to reduce our reliance on chemical controls. These include resistances against diseases, pests, and traits for useful agronomic characters such as yield, specific gravity, chipping qualities, and suppression of enzymatic browning. This paper summarizes some of these qualities, and provides an overview of germplasm availability and taxonomy of the wild species. The major potato of commerce,Solanum tuberosum L., is the fourth most important food crop in the world after rice, wheat and maize. It is grown in more countries than any other crop but maize, and forms the staple crop of many societies. Over 280 million metric tons were grown worldwide in 1989, with Eastern Europe growing 46%, Asia 22%, Western Europe 17%, North America 7%, Latin America 5%, and Africa 3% (2). It is the leading vegetable crop in acreage and farm value in the United States, with 1.2 million acres planted in 1991, with a value of sales almost two and one-half billion dollars (53).Solanum tuberosum is one species of a group of seven cultivated and 216 additional tuber-bearing, and nine non-tuber-bearing wild relatives, all classified by Hawkes (41) in the genusSolanum, sectionPetota Dumort The purposes of this paper are threefold: 1) to provide examples of the proven and potential utility of wild and cultivated landrace members of sect.Petota for reducing our reliance on chemical controls for many pests and diseases that affect commercial cultivars, 2) to provide an overview of the status of germplasm availability of these species, and 3) to highlight the benefits for continuing germplasm collections and systematic studies of the group.