Sandra Knapp

Fruit development and ripening.

Fruiting structures in the angiosperms range from completely dry to highly fleshy organs and provide many of our major crop products, including grains. In the model plant Arabidopsis, which has dry fruits, a high-level regulatory network of transcription factors controlling fruit development has been revealed. Studies on rare nonripening mutations in tomato, a model for fleshy fruits, have provided new insights into the networks responsible for the control of ripening. It is apparent that there are strong similarities between dry and fleshy fruits in the molecular circuits governing development and maturation. Translation of information from tomato to other fleshy-fruited species indicates that regulatory networks are conserved across a wide spectrum of angiosperm fruit morphologies. Fruits are an essential part of the human diet, and recent developments in the sequencing of angiosperm genomes have provided the foundation for a step change in crop improvement through the understanding and harnessing of genome-wide genetic and epigenetic variation.

Agriculture: Feeding the future

Humanity depends on fewer than a dozen of the approximately 300,000 species of flowering plants for 80% of its caloric intake. And we capitalize on only a fraction of the genetic diversity that resides within each of these species. This is not enough to support our food system in the future. Food availability must double in the next 25 years to keep pace with population and income growth around the world. Already, food-production systems are precarious in the face of intensifying demand, climate change, soil degradation and water and land shortages. Farmers have saved the seeds of hundreds of crop species and hundreds of thousands of ‘primitive’ varieties (local domesticates called landraces), as well as the wild relatives of crop species and modern varieties no longer in use. These are stored in more than 1,700 gene banks worldwide. Maintaining the 11 international gene-bank collections alone costs about US

Biodiversity Conservation and the Millennium Development Goals

18 million a year.

Comparison of AFLPs with other markers for phylogenetic inference in wild tomatoes [Solanum L. section Lycopersicon (Mill.) Wettst.]

Any near-term gains in reducing extreme poverty will be maintained only if environmental sustainability is also achieved. The Millennium Development Goals (MDGs) are designed to inspire efforts to improve peoples lives by, among other priorities, halving extreme poverty by 2015 (1). Analogously, concern about global decline in biodiversity and degradation of ecosystem services (2) gave rise in 1992 to the Convention on Biological Diversity (CBD). The CBD target “to achieve by 2010 a significant reduction of the current rate of biodiversity loss” was incorporated into the MDGs in 2002. Our lack of progress toward the 2010 target (3, 4) could undermine achievement of the MDGs and poverty reduction in the long term. With increasing global challenges, such as population growth, climate change, and overconsumption of ecosystem services, we need further integration of the poverty alleviation and biodiversity conservation agendas.

Indigenous diversity of Cassava: Generation, maintenance, use and loss among the Amuesha, Peruvian upper Amazon

ac.uk Wild tomatoes (Solanum section 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; multiple-copy), the single-copy nuclear encoded Granule-bound 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. peruvianum s.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 ochranthum is supported as sister to wild tomatoes, and S. habrochaites and S. pennellii reside in a basal polytomy in the tomato clade.

Solanaceae--a model for linking genomics with biodiversity.

For cassava (Manihot esculenta Euphorbiaceae), results from field collection, semistructured interviews, phenetic and cluster analyses, and Global Information Systems (G1S) indicate that cassava phenotypes vary with elevation and topography, but less with soils or pests and diseases. Amuesha women with a sense of tradition maintain many cassava varieties along with associated myths, songs, names and indigenous production. The shaman plays a key role in breeding new and maintaining traditional cassava germplasm, while the rest of the tribe nurtures cassava germplasm dynamics through collecting, trading, stealing, maintaining favored cassava varieties, and purging the less desirable. The future of cassava diversity is of concern to some Amuesha as production and market interests surmount more traditional attention to variety.ResumenResultados de colectas de campo, entrevistas semi-estructuradas, analisis fenetica y de conglomerados y sistemas de information geografica indican quefenotipos de yuca (Manihot esculenta Euphorbiaceae) varían con altura y topografía, pero menos con suelos o plagas insectiles y enfermidades. Las mujeres Amuesha, arraigadas en sus tradiciones indígenas, conservan muchas variedades como parte de un mundo cultural de canciones, mitos, nombres de variedades y métodos tradicionales de uso alrededor de la yuca. El curandero tiene un papel clave en seleccionar nuevas variedades y mantener variedades tradicionales, mientras una buena parte de todos los Amuesha cuidan la dinámica del germoplasma de yuca colectando, intercambiando, prestando sin permiso, manteniendo las mejores variedades y abandonando las variedades no-deseadas. El futuro de la biodiversidad de la yuca is una preocupación de algunos (as) Amuesha por la creciente importancia de criterios de mercado y de productividad en vez de la atención traditional a la misma biodiversidad.

Solanaceae III : taxonomy, chemistry, evolution

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.

Nomenclatural changes and a new sectional classification in Nicotiana (Solanaceae)

Proceedings of Third International Conference on Solanaceae with 35 papers on alkaloid chemistry, drug therapy, biotechnology and breeding research.

New Species of Wild Tomatoes (Solanum Section Lycopersicon: Solanaceae) from Northern Peru

Recent studies using regions of the nuclear and plastid genomes have shown that T. H. Goodspeeds sectional groupings in Nicotiana are for the large part upheld. However, we have shown that in several cases sectional membership should be revised. Here we present a revised outline of the sections of Nicotiana with lists of their component species. Relationships of the sections as defined can be seen in accompanying figures. Two sectional names with priority over those in current use are introduced (N. sect. Polydicliae & sect. Petunioides) and one new section, N. sect. Sylvestres, is described here. Two species names are changed to those with priority over those adopted by Goodspeed in his monograph of the genus: N. obtusifolia for N. trigonophylla and N. quadrivalvis for N. bigelovii. Synonymies are provided for each of these names. A short morphological description is provided for each section, along with a generalized distribution and a list of accepted species names.

Plant evolution and endemism in Andean South America: An introduction

Abstract Solanum arcanum and S. huaylasense, two new wild tomato species segregated from Solanum peruvianum sensu lato, are described and illustrated. These two new species are placed in a key with two other segregates of S. peruvianum sensu lato: S. peruvianum sensu stricto and S. corneliomulleri, and the morphologically similar species S. chilense. We also present a list of all 13 species of wild tomatoes we recognize, and their equivalent former names in Lycopersicon.