Database on diagnosis of arthropod diseases in the Internet of the Julius Kühn‐Institute

A database on diagnosis of diseases of insects and other arthropods is available in a German and English version at http://arthropodenkrankheiten.jki.bund.de . It is based on 55 years of diagnostic investigations of living, diseased, or dead arthropods of about 450 species at the ‘Institute for Biological Control’ in Darmstadt, Germany. Results of 1951 accessions with several thousands of diagnosed specimens from 1953 to 2008 are presented. The diagnosed pathogens belong to six groups: viruses, bacteria including rickettsiae, fungi, microsporidia (recently assigned to fungi), protists, and nematodes. The database will be updated regularly.     

The Genus Cladophora Kützing (Ulvophyceae) as a Globally Distributed Ecological Engineer

The green algal genus Cladophora forms conspicuous nearshore populations in marine and freshwaters worldwide, commonly dominating peri‐phyton communities. As the result of human activities, including the nutrient pollution of nearshore waters, Cladophora‐dominated periphyton can form nuisance blooms. On the other hand, Cladophora has ecological functions that are beneficial, but less well appreciated. For example, Cladophora has previously been characterized as an ecological engineer because its complex structure fosters functional and taxonomic diversity of benthic microfauna. Here, we review classic and recent literature concerning taxonomy, cell biology, morphology, reproductive biology, and ecology of the genus Cladophora, to examine how this alga functions to modify habitats and influence littoral biogeochemistry. We review the evidence that Cladophora supports large, diverse populations of microalgal and bacterial epiphytes that influence the cycling of carbon and other key elements, and that the high production of cellulose and hydrocarbons by Cladophora‐dominated periphyton has the potential for diverse technological applications, including wastewater remediation coupled to renewable biofuel production. We postulate that well‐known aspects of Cladophora morphology, hydrodynamically stable and perennial holdfasts, distinctively branched architecture, unusually large cell and sporangial size and robust cell wall construction, are major factors contributing to the multiple roles of this organism as an ecological engineer.     

Nutlet micromorphology of Carex section Rhomboidales sensu Kükenthal (Cyperaceae) and its systematic implications

The sectional delimitation of Carex section Rhomboidales sensu Kükenthal (1909) is problematic and, here, we provide contributions to a systematic understanding of nutlet micromorphology in section Rhomboidales. Nutlet micromorphology of 87 samples representing 71 taxa was investigated using scanning electron microscopy and nine nutlet types were recognized. Although some closely related taxa show similarities, nutlet morphology in section Rhomboidales is stable at the species level and is reliable for species identification. Based on the nutlet characters, section Rhomboidales is delimited and emended as having nutlet rhombic–ovoid, trigonous; beaks conspicuous, erect, rarely curved or coiled; periclinal walls of epidermal cells straight, with zero to two silica bodies. The species with nutlets of the C. harlandii‐type and C. thibetica‐type are included, and species of the C. chinensis‐type and C. macrandrolepsis‐type are ascribed to section Mitratae and section Infossae, respectively. Carex longirostrata and C. pseudolongirostrata (= C. nodaeana), formerly ascribed to section Careyanae or section Depauperatae, are well supported as members of section Rhomboidales. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 123–143.     

30. Gerhard Follmann: Zur Bedeutung der Salzbestäubung für den Wasserhaushalt von Küstenflechten

Nach gravimetrischen Untersuchungen an Chiodecton cerebriforme Mont., Roccella portentosa (Mont.) Darb. und Roccellaria mollis (Hampe) Zahlbr. können hygroskopische Salzstaubkrusten an Küstenflechten deren Wasserdampfaufnahme fördern. Zwischen Grenzschicht und Flechtenlager vermittelt offenbar ein aktives Transportsystem.