Taxonomic studies in the Fuirena pubescens complex (Cyperaceae) in Kenya

Muasya. A. M. & Baauar, S. R. 1995. Taxonomic studies in the Fuirena pubescens complex (Cyperaceae) in Kenya. — Nord. J. Bot. 15: 407–410. Copenhagen. ISSN 0107–055X.
Three taxa in the Fuirena pubescens complex were investigated morphologically, palynologically, and cytologically in order to determine their taxonomic identity and appropriate rank. The taxa differ in both morphology and chromosome number. The three former varieties, F. pubescens var. pubescens , var. major , and var. buchananii , are here recognised as distinct species, with var. major and var. buchananii being reinstated as F. pachyrrhiza and F. welwitschii , respectively. Fuirena pubescens and F. pachyrrhiza have terete spikelets and leaf blades more than 5 mm wide, but the former has a meiotic chromosome number of n=21 and white entire nutlets, while the latter has a chromosome number of n=24 and dark-greenish tuberculate nutlets. Fuirena welwitschii is distinguished by having a 5-angular spikelets, chromosome number n=40, and brownish tuberculate nutlets.     

Validation of Ranunculus ficaria L. ssp. fertilis Clapham ex Lqaard (Ranunculaceae)

The origin and status of the name Ranunculus ficaria L. var. or ssp. fertilis is discussed and the infraspecific name is validated. — Flora Nordica Notes No. 27.     

Allozyme variation and genetic integrity of Dactylorhiza incarnata (Orchidaceae)

Eleven Danish populations of the diploid Dactylorhiza incarnata s.lat. have been examined for allozyme variation in DIA, PGD, PGI, PGM, SKD, TP1, and UGPP. The results reveal a deficiency of heterozygotes in several populations. Possible reasons for this deficiency are considered. The results also indicate that no genetic barrier seems to prevent gene flow between D. incarnata var. incarnata , var. dunensis , and var. ochrantha — and some indication exists that a considerable amount of gene exchange takes place between sympatric populations of var. incarnata and var. ochrantha . On the other hand, there is no sign of recent introgression between D. incarnata s.lat. and any of the sympatric tetraploid species ( D. maculata, D. majalis, D. purpurella s.lat.). It is suggested that knowledge on the various degrees of genetic integrity of morphologically recognizable entities should be elaborated and subsequently utilized for a biosystematic approach to Dactylorhiza .     

Die Wirkungsweise von Cercosporella herpotricboides Fron, dem Erreger der Halmbruchkrankheit des Getreides

In halt: 1. Einleitung und Aufgabenstellung.—2. Art und Ausmaß der Scnäden im Feld-versuch.—3. Wirkungen des Krankheitserregers auf Sommergetreide.—4. Bekämpfungsmöglichkeiten.—5. Besprechung der Ergebnisse.—Zusammenfassung.—Summary. —Literaturverzeichnis.     

Light-induced linear dichroism in photoreversibly photochromic sensor pigments. – IV. Lack of chromophore rotation in phycochrome b immobilized in vitro

In photochromic pigments, immobilized on Sepharose beads to prevent reorientation of the molecules, linear absorption dichroism can be induced with plane-polarized light. This phenomenon was used to study the relation between the carrier protein and the chromophore in the photochromic cyanobacterial pigment, phycochrome b , from Tolypothrix distorta var. symplocoides Hansgirg, strain UTEX 424 (formerly IUCC 424). It was found that the transition moment of the chromophore has the same direction with respect to the protein in the long-wavelength and the short-wavelength forms of phycochrome b. This contrasts to earlier results for phytochrome in higher plants, in which the transition moment was found to rotate 32° (or 180°—32°) when the long-wavelength form was converted to the short-wavelength form or vice versa.     

Measuring tolerance to herbivory: accuracy and precision of estimates made using natural versus imposed damage

Abstract.— Tolerance to herbivory (the ability of a plant to incur herbivore damage without a corresponding reduction in fitness) can be measured using either naturally occurring or imposed herbivore damage. After briefly reviewing some of the advantages and disadvantages of these approaches, we present calculations describing the degree to which estimates of tolerance will be biased by environmental variables that affect both herbivory and fitness. With naturally occurring herbivory the presence of environmental variables that are correlated with herbivory and fitness will result in biased estimates of tolerance. In contrast, estimates obtained from experiments in which herbivory is artificially imposed will be unbiased; however, under a wide range of parameter values these estimates will be less precise than estimates obtained from experiments in which herbivory is not manipulated.     

Das Wirtsspektrum von Phytophthora cactorum (Leb. et Cohn) Schroet.

In halt: 1. Historische Betrachtungen. — 2. Das Wirtsspektrum. — 3. Die Bedeutung der Pilzherkunft. — 4. Das Wirtsspektrum als Artmerkmal. — Zusammenfassung. — Summary. — Literaturverzeichnis.     

Eine Triebspitzenerkrankung der Weymouthskiefer (Pinus strobus L.), verursacht durch Scleroderris lagerhergii Gremmen

Inhalt: Einleitung. – 1. Krankheitsbild.—2. Der Krankheitserreger und seine Begleit-pilze.—3. Regenerationserscheinungen.—Zusammenfassung.—Summary.—Literatur- verzeichnis.     

Isolierung des Himbeerringfleckenvirus (raspberry ringspot virus) aus Roter Johannisbeere (Ribes rubrumL.)

Inhalt: 1. Einleitung.—2. Material und Methoden.—3, Ergebnisse: a) Reaktion von Obstgehölzen; b) Reaktion von krautlgen Testpflanzen; c) Physikalische Eigenschaften; d) Prämumtätsversuche; e) Serologische Untersuchungen.—4. Diskussion.—Zusammen-fassung.—Summary.—Literaturverzeichnis.     

Beiträge zur Analyse der Vektoreignung einiger wirtschaftlich wichtiger Blattlausarten und-rassen

Inhalt: A. Einleitung.—B. Bisher bekannte intraspezifische Unterschiede in den Vektoreigenschaften bei virusübertragenden Homopteren.—C. Die möglichen Ursachen für die untcrschicdliche Vcktorbefähigung der Blattlausrassen.—D. Material und Methode.—E. Übertragungsversuche. a) Die benutztcn Blattlausstamme und Altersstadien; b) Testpflanzen; c) Der Infektionserfolg in Abhängigkeit von der Infektionsquelle; d) Ergebnisse von Gruppenübertragungen; e) Einzeltierversuche; f) Versuche mit dem Bastard Myzus persicae (Sulz.) × Myzus myosotidis (Börn.).—F. Besprechung der Ergebnisse und Schlußfolgerungen.—Zusammenfassung.—Summary.—Literaturverzeichnis.     

Licht-und elektronenmikroskopische Untersuchungen der Chloroplasten chlorotischer Maispflanzen

In halt: I. Einleitung. — II. Material und Methode. — III. Untersuchungen an Chloroplasten bei Mangelchlorose. — IV. Untersuchungen an Chloroplasten bet funktioncller Chlorose. — V. Diskussion. — Zusammenfassung. — Summary. – Literaturverzeichnis.     

Untersuchungen zur Identifizierung und Differenzierung des Blattrollvirus der Kirsche (cherry leaf roll virus)

Inhalt: A. Symptomatologie.—B. Identifizierung. 1. Material und Methoden; 2. Ergeb-nisse; a) Reaktion von Obstsorten oder -arten, b) Reaktion von krautigen Testpflanzen, c) Eigenschaften des Virus in vitro, d) Partielle Reinigung des Virus, e) Serologische Untersuchungen, f) Partikelgestalt.—C. Differenzierung durch Testpflanzen.—D. Diskussion.—Zusammenfassung.—Summary.—Literaturverzeichnis.     

ON THE STRUCTURE OF TWO NEW GANGLIOSIDES FROM BEEF BRAIN

Abstract— Two new gangliosides were isolated in pure form from beef brain. They were provisionally named ganglioside G5a and G5b. Ganglioside GSa is a monosialoganglioside containing fucose. Its basic neutral glycosphingolipid core is the gangliotetraose ceramide: Gal (1 —> 3) GalNac (1—> 4) Gal (1 —> 4) Glc (1—>) ceramide, most likely with β-linkages. Fucose is linked to the 2-position of external galactose, N -acetylneuraminic acid to the 3- position of internal galactose. Ganglioside G5b is a mixture of at least two isomeric disialogangliosides containing N -acetylneuraminic acid and N -glycolylneura-minic acid. The major isomer has the following structure: NeuNac (α,2—>3) Gal (β,1—>3) GalNac (β, 1 —> 4) (NeuNglα, 2 —> 3) gal (β,1—>4) Glc (β,1 —>)-ceramide. The minor isomer contains N -acetylneur-aminic acid and N -glycolylneuraminic acid in an inverted linkage position.     

Reviews

Book reviewed in this article:
Neutral Models in Biology. —Matthew H. Nitecki and Antoni Hoffman (eds).
The Expanding Earth, a Symposium .—S. Warren Carey (Convener and Editor).
Theories of the Earth and Universe: a History of Dogma in the Earth Sciences. —S. Warren Carey.
Classification, Evolution and Phylogeny of the Families of Dicotyledons. —Aaron Goldberg.     

Reviews

Book reviewed in this article:
Gentlemanly Cladistics: Phylogenetic Reconstruction in Paleontology .—Robert M. Schoch.
Coevolution and Systematics .—A. R. Stone and D. L. Hawksworth (eds.).
Systematic and Taxonomic Approaches in Palaeobotany .—Robert A. Spicer and Barry A. Thomas (eds.).
Cladistic Biogeography —Christopher J. Humphries and Lynne R. Parenti.
Chondrichthyes II: Mesozoic and Cenozoic Elasmobranchii —H. Cappetta.
Handbook of Paleoichthyology, vol. 3B, Fischer     

Reviews

Book reviewed in this article:
Evolution and Classification: The Reformation of Cladism .—Mark Ridley.
Phylogenetic Systematics of the Drynarioideae (Polypodiaceae) .—M. C. Roos.
Oxford Surveys in Evolutionary Biology: Volume 1 .—Richard Dawkins and Mark Ridley (eds.).
Oxford Surveys in Evolutionary Biology, Volume 2 .—R. Dawkins and M. Ridley (eds.) 1985.
An Illustrated Guide to the Protozoa .—John J. Lee, Seymour H. Hutner, and Eugene Bovee (eds.).
Ontogeny and Systematics of Fishes .—H. G. Moser, W. J. Richards, D. M. Cohen, M. P. Fahay, A. W. Kendall, Jr., and S. L. Richardson (eds.).
Morphometrics in Evolutionary Biology .—F. Bookstein, B. Chernoff, R. Elder, J. Humphries, G. Smith, and R. Strauss.     

Reviews

Book reviewed in this article:
Cladistics: Perspectives on the Reconstruction of Evolutionary History. — Thomas Duncan and Tod F. Stuessy (eds.). 1984.
Das Phylogenetische System. — Peter Ax. 1984.
Beyond Neo-Darwinism: An Introduction to the New Evolutionary Paradigm. — M.-W. Ho and P. T. Saunders (eds.). 1984.
The Great Chain of History: William Buckland and the English School of Geology (1814–1849). — Nicolaas A. Rupke. 1983     

Avian foraging studies: an overlooked source of distribution data for macroecological and conservation studies

Macroecological and biogeographical studies and their applicability for biological conservation vitally depend on distribution data. These are usually taken from distribution atlases and databases or maps found in identification guides. A previous study pointed to another little explored source of data — local faunistic studies. Here, I would like to draw attention to another potential source. Papers that analysed the food composition of some taxa (e.g. insectivorous birds) are an overlooked source of rich information on taxa distributions. These studies frequently include an 'Appendix' with a list of food items determined to the species level. These studies also contain data on abundances, number of samples, sampling time, and geographical location as a rule. Foraging birds naturally provide data on invertebrate distributions with good spatio-temporal coverage and reasonably large samples. Importantly, birds frequently collect rare and by entomological methods hardly detectable species (i.e. those living high, in tree canopies, in very dense vegetation, or with secretive lifestyle). Data from bird dietary studies may help to ameliorate one of the most serious problems in distribution studies — zero inflation. I briefly discuss pros and cons of this so far neglected source of biogeographical data.     

Reviews

Book reviewed in this article:
The Ancestry of the Vertebrates. —R. P. S. Jefleries.
The Blind Watchmaker .—R. Dawkins.
Darwinism: The Refutation of a Myth. —Søren Lavtrup.