Summary Austin, D. F. & Huáman, Z.: A synopsis of Ipomoea (Convolvulaceae) in the Americas. – Taxon 45: 3‐38. 1996. – ISSN 0040‐0262. A total of 339 taxa (327 species, five varieties, five subspecies) currently are recognized in the Americas, with the caveat that additional taxa exist that are unstudied and undescribed. Those species recognized are placed, when possible, in infrageneric categories. Known distributions are given for each taxon. Synonyms and names of uncertain application are listed.
Cultivated potatoes have been classified as species under the International Code of Botanical Nomenclature (ICBN) and as cultivar‐groups under the International Code of Nomenclature of Cultivated Plants (ICNCP); both classifications are still widely used. This study examines morphological support for the classification of landrace populations of cultivated potatoes, using representatives of all seven species and most subspecies as outlined in the latest taxonomic treatment. These taxa are S. ajanhuiri, S. chaucha, S. curtilobum, S. juzepczukii, S. phureja subsp. phureja, S. stenotomum subsp. stenotomum, S. stenotomum subsp. goniocalyx, S. tuberosum subsp. andigenum, and S. tuberosum subsp. tuberosum. The results show some phenetic support for S. ajanhuiri, S. chaucha, S. curtilobum, S. juzepczukii, and S. tuberosum subsp. tuberosum, but little support for the other taxa. Most morphological support is by using a suite of characters, all of which are shared with other taxa (polythetic support). These results, combined with their likely hybrid origins, multiple origins, evolutionary dynamics of continuing hybridization, and our classification philosophy, leads us to recognize all landrace populations of cultivated potatoes as a single species, S. tuberosum, with the eight cultivar‐groups: Ajanhuiri Group, Andigenum Group, Chaucha Group, Chilotanum Group, Curtilobum Group, Juzepczukii Group, Phureja Group, and Stenotomum Group. We defer classification of modern cultivars, traditionally classified in Tuberosum Group, to a later study.
Genebank collection databases can be used for ecogeographical studies under the assumption that the accessions are a geographically unbiased sample. We evaluated the representativeness of a collection of wild potatoes from Bolivia and defined and assessed four types of bias: species, species-area, hotspot, and infrastructure. Species bias is the sampling of some species more often than others. Species-area bias is a sampling that is disproportionate to the total area in which a species is found. Hotspot bias is the disproportionate sampling of areas with high levels of diversity. Infrastructure bias is the disproportionate sampling of areas near roads and towns. Each of these biases is present in the Bolivian wild potato collection. The infrastructure bias was strong: 60% of all wild potato accessions were collected within 2 km of a road, as opposed to 22%, if collections had been made randomly. This analysis can serve as a guide for future collecting trips. It can also provide baseline information for the application of genebank data in studies based on geographic information systems. Evaluación de la Representatividad Geográfica de las Colecciones de Bancos de Genes: El Caso de las Papas Silvestres BolivianasResumen: Las bases de datos de los bancos de germoplasma pueden ser usadas para estudios ecogeográficos bajo el supuesto que las entradas constituyen una muestra geográficamente imparcial. Evaluamos la representatividad geográfica de una colección de papas silvestres de Bolivia y definimos y evaluamos cuatro tipos de sesgos: sesgos de especie, de especie-área, de áreas con gran diversidad (hotspot), y de infraestructura. El sesgo de especie implica el muestrear más algunas especies que otras. El sesgo de especie-área es un muestreo que es desproporcionado con respecto al total del área en la cual se encuentra una especie. El sesgo de "hotspot" es el muestreo desproporcionado de áreas con niveles altos de diversidad. El sesgo por infraestructura es aquel muestreo desproporcionado de áreas cercanas a carreteras y pueblos. Cada uno de estos sesgos se presenta en la colección de papas silvestres de Bolivia. El sesgo por infraestructura fue muy elevado: 60% de todas las entradas de papas silvestres fueron colectados dentro de un radio de 2 km de distancia de las carreteras, cuando se debería esperar un 22% si las colectas se hubieran hecho de manera aleatoria. Este análisis puede servir como guía para futuras exploraciones y proporciona una base para la aplicación de los datos de bancos de genes en estudios basados en sistemas de información geográfica. *
Amplified fragment length polymorphism fingerprinting was applied to survey the genetic diversity of primitive South American Gossypium barbadense cotton for establishing a possible link to its pre-Columbian expansion. New germplasm was collected along coastal Peru and over an Andean transect in areas where most of the archaeological evidence relating to cotton domestication has been recorded. Gene bank material of three diploid (G. raimondii, G. arboreum, and G. herbaceum) and four allotetraploid cotton species (G. hirsutum, G. mustelinum, G. tomentosum and additional G. barbadense) was added for inter- and intra-specific comparison. Eight primer combinations yielded 340 polymorphic bands among the 131 accessions. The obtained neighbor joining and unweighted pair-group method with arithmetic means are in full agreement with the known cytogenetics of the tetraploid cottons and their diploid genome donors. The four tetraploid species are clearly distinct based on taxonomic classification. The genetic diversity within G. barbadense reveals geographic patterns. The locally maintained cottons from coastal Peru display a distinct genetic diversity that mirrors their primitive agro-morphological traits. Accessions from the northernmost coast of Peru and from southwestern (SW) Ecuador cluster basal to the east-of-Andes accessions. The remaining accessions from Bolivia, Brazil, Columbia, Venezuela, and the Caribbean and Pacific islands cluster with the east-of-Andes accessions. Northwestern Peru/SW Ecuador (the area flanking the Guayaquil gulf) appears to be the center of the primitive domesticated G. barbadense cotton from where it spread over the Andes and expanded into its pre-Columbian range.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.