Colletotrichum acutatum is known as an important anthracnose pathogen of a wide range of host plants worldwide. Numerous studies have reported subgroups within the C. acutatum species complex. Multilocus molecular phylogenetic analysis (ITS, ACT, TUB2, CHS-1, GAPDH, HIS3) of 331 strains previously identified as C. acutatum and other related taxa, including strains from numerous hosts with wide geographic distributions, confirmed the molecular groups previously recognised and identified a series of novel taxa. Thirty-one species are accepted, of which 21 have not previously been recognised. Colletotrichum orchidophilum clusters basal to the C. acutatum species complex. There is a high phenotypic diversity within this complex, and some of the species appear to have preferences to specific hosts or geographical regions. Others appear to be plurivorous and are present in multiple regions. In this study, only C. salicis and C. rhombiforme formed sexual morphs in culture, although sexual morphs have been described from other taxa (especially as laboratory crosses), and there is evidence of hybridisation between different species. One species with similar morphology to C. acutatum but not belonging to this species complex was also described here as new, namely C. pseudoacutatum. Taxonomic novelties New combinations - Colletotrichum limetticola (R.E. Clausen) Damm, P.F. Cannon & Crous, C. lupini (Bondar) Damm, P.F. Cannon & Crous, C. salicis (Fuckel) Damm, P.F. Cannon & Crous. New species - C. acerbum Damm, P.F. Cannon & Crous, C. australe Damm, P.F. Cannon & Crous, C. brisbanense Damm, P.F. Cannon & Crous, C. cosmi Damm, P.F. Cannon & Crous, C. costaricense Damm, P.F. Cannon & Crous, C. cuscutae Damm, P.F. Cannon & Crous, C. guajavae Damm, P.F. Cannon & Crous, C. indonesiense Damm, P.F. Cannon & Crous, C. johnstonii Damm, P.F. Cannon & Crous, C. kinghornii Damm, P.F. Cannon & Crous, C. laticiphilum Damm, P.F. Cannon & Crous, C. melonis Damm, P.F. Cannon & Crous, C. orchidophilum Damm, P.F. Cannon & Crous, C. paxtonii Damm, P.F. Cannon & Crous, C. pseudoacutatum Damm, P.F. Cannon & Crous C. pyricola Damm, P.F. Cannon & Crous, C. rhombiforme Damm, P.F. Cannon & Crous, C. scovillei Damm, P.F. Cannon & Crous, C. sloanei Damm, P.F. Cannon & Crous, C. tamarilloi Damm, P.F. Cannon & Crous, C. walleri Damm, P.F. Cannon & Crous. Typifications: Epitypifications - C. acutatum J.H. Simmonds, C. limetticola (R.E. Clausen) Damm, P.F. Cannon & Crous, C. nymphaeae (Pass.) Aa, C. phormii (Henn.) D.F. Farr & Rossman, C. salicis (Fuckel) Damm, P.F. Cannon & Crous. Lectotypifications - C. nymphaeae (Pass.) Aa, C. orchidearum Allesch.

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Aim of the study This study uses historical texts in order to obtain information on the natural products used in traditional medicines in European/Mediterranean therapeutics over the last two millennia. The information obtained may lead to new directions in the area of drug discovery, as recent research has demonstrated the continued promise of looking to natural products for bioactive compounds. Researchers have increasingly turned to traditional medicines to provide clues as to which natural products to investigate, but the oral traditions on which much of this medical knowledge rests are often unstable. Thus researchers have been prompted to use historical medical texts, as this study does, to find potential sources of new drugs. Materials and methods This study uses twelve Mediterranean/European medical texts from the 5th century BC to the 19th century AD to compile a list of the most commonly used "simples"--or single action drugs substances--used in therapeutics in traditional European medicine. This list was then compared to present-day herbal pharmacopoeia as represented by the National Institutes of Health (NIH). Results This study finds that traditional European materia medica was based on a Dioscoridean tradition that lasted through the 19th century with remarkably little variation, but is significantly different from the present-day herbal pharmacopoeia according to the NIH. Conclusions The most prominent simples in the European/Mediterranean medical tradition can provide clues to further bioactive compounds that have not as of yet been fully exploited for their potential, but were clearly of great use in the past.

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Background and aims Genome size (DNA C-value) data are key biodiversity characters of fundamental significance used in a wide variety of biological fields. Since 1976, Bennett and colleagues have made scattered published and unpublished genome size data more widely accessible by assembling them into user-friendly compilations. Initially these were published as hard copy lists, but since 1997 they have also been made available electronically (see the Plant DNA C-values database http://www.kew.org/cval/homepage.html). Nevertheless, at the Second Plant Genome Size Meeting in 2003, Bennett noted that as many as 1000 DNA C-value estimates were still unpublished and hence unavailable. Scientists were strongly encouraged to communicate such unpublished data. The present work combines the databasing experience of the Kew-based authors with the unpublished C-values produced by Zonneveld to make a large body of valuable genome size data available to the scientific community. Methods C-values for angiosperm species, selected primarily for their horticultural interest, were estimated by flow cytometry using the fluorochrome propidium iodide. The data were compiled into a table whose form is similar to previously published lists of DNA amounts by Bennett and colleagues. Key results and conclusions The present work contains C-values for 411 taxa including first values for 308 species not listed previously by Bennett and colleagues. Based on a recent estimate of the global published output of angiosperm DNA C-value data (i.e. 200 first C-value estimates per annum) the present work equals 1.5 years of average global published output; and constitutes over 12 % of the latest 5-year global target set by the Second Plant Genome Size Workshop (see http://www.kew.org/cval/workshopreport.html). Hopefully, the present example will encourage others to unveil further valuable data which otherwise may lie forever unpublished and unavailable for comparative analyses.

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Our objectives were to identify substances produced by plant roots that might act as nutritional mediators of specific plant-bacterium relationships and to delineate the bacterial genes responsible for catabolizing these substances. We discovered new compounds, which we call calystegins, that have the characteristics of nutritional mediators. They were detected in only 3 of 105 species of higher plants examined: Calystegia sepium, Convolvulus arvensis (both of the Convolvulaceae family), and Atropa belladonna. Calystegins are abundant in organs in contact with the rhizosphere and are not found, or are observed only in small quantities, in aerial plant parts. Just as the synthesis of calystegins is infrequent in the plant kingdom, their catabolism is rare among rhizosphere bacteria that associate with plants and influence their growth. Of 42 such bacteria tested, only one (Rhizobium meliloti 41) was able to catabolize calystegins and use them as a sole source of carbon and nitrogen. The calystegin catabolism gene(s) (cac) in this strain is located on a self-transmissible plasmid (pRme41a), which is not essential to nitrogen-fixing symbiosis with legumes. We suggest that under natural conditions calystegins provide an exclusive carbon and nitrogen source to rhizosphere bacteria which are able to catabolize these compounds. Calystegins (and the corresponding microbial catabolic genes) might be used to analyze and possibly modify rhizosphere ecology.

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