Phytosociological characteristics of theRondeletio correifoliae-Andropogonetum multinervosi ass. nova (Sierra de la Siguanea,Isla de la Juventud,Cuba)

The contribution deals with the phytocenological analysis of theRondeletio correifoliae-Andropogonetum multinervosi, an endemic savanna association occuring on the Siguanea Hills (Sierra de la Siguanea) near the Colony Hotel.     

The Electrical Conductivity of Bovine Milk in Mastitis Diagnosis

The electrical conductivity (EC) of milk is mainly a function of the electrolyte concentration in the milk and therefore raised in mastitis. The present investigation was aimed at elaborating, if possible, a diagnostic model for screening purposes based on EC determinations and consistent with the diagnostic procedures and interpretations commonly used in laboratory milk diagnosis in the Nordic countries (Klastrup 1975). According to this diagnosis (here called reference diagnosis) cell numbers above 300,000/ml (cell count or the corresponding CMT-score) in foremilk quarter samples during the main part of the lactation period and significantly above the lowest value on within-udder comparison during late lactation are considered indicative of mastitis and bacteriological examinations are made when called for.     

Cholinesterase activity in some species of theAllium genus

In partly purified protein complexes obtained from 22 species of theAllium genus and 6 cultivars ofAllium cepa the activity of cholinesterases was detected and measured using the method of Ellman et al. The degree of its inhibition with 10^-4 M neostigmine was also tested. It was found that the activity of cholinesterase differed in individual species up to two hundred times, while the differences in the inhibitory activity of 10^-4 M neostigmine occurred only in a few cases. Individual sections and cultivars could not be characterized on the basis of the differences in the activities of the cholinesterases. Of all the sections that ofPhyllodolon shows the highest average activity. In the case of the tested cultivars distinctly the lowest activity was observed in cv. Kastická. The values of the enzymatic activity measured by Ellman’s method in this plant material include the activity of specific and unspecific cholinesterases and the part uninhibitable by neostigmine.     

Developmental changes in gene expression during pollen differentiation and maturation inNicotiana tabacum L

Total and polysome-bound ribosomes and the uptake and incorporation of³H-uridine and¹⁴C-leucine were examined in dividing microspores and in pollen grains isolated from anthers of 6 different developmental stages. Direct evidence was obtained that the formation of cytoplasm of the vegetative cell following microspore division is related to a rapid activation of RNA and protein synthesis and of ribosomes in differentiating pollen. Total ribosomes associated with gametophytic programme rose about 10times and the process of differentiation was accompanied by a rapid increase in uptake capacity of pollen grains for both uridine and leucine. Pollen development after cytoplasm synthesis and starch deposition continued by pollen maturation, which was characterized by a decline in RNA synthesis, dissociation of polysomes and by a further rise of transport activity of pollen grain wall for exogenous substrates, indicating probable pollen adaptation for utilization of metabolites from the degenerating tapetal cytoplasm.     

Comparison of malate dehydrogenase isoenzymes in someAllium species by isoelectric focusing

Malate dehydrogenase isoenzymes were studied in tenAllium species and in six cultivars ofA. cepa by isoelectric focusing in polyacrylamide gel with Ampholine pH 3.5–10.0. Using this method better resolution was obtained than by polyacrylamide gel electrophoresis. The number of MDH isoenzymes obtained by isoelectric focusing is from five to ten in the range of pH 3.65 to 6.75. MDH isoenzymes can be used for characterization on the level of species and cultivars (inA. cepa), but its use on the level of sections and subgenera is questionable.     

The comparison of seed protein patterns within the genusArachis by polyacrylamide gel electrophoresis

The seed protein patterns of 12Arachis species were compared by polyacrylamide gel electrophoresis (PAGE), similarities between patterns were measured by the Jaccard index. Results obtained confirm the close relationships established between members of the genus on morphological grounds and support the more recent classification schemes.A. villosa andA. correntina could well be regarded as distinct species on grounds of protein differences whileA. macedoi andA. villosulicarpa (although members of the same section, Extranervosae) show considerable differentiation of their protein patterns. Surprisingly, the formA. ×batizogaea showed less similarity in protein pattern to those of its parental species than might have been expected. The principle value of seed protein pattern data appears to be in distinguishing species within sections.     

Foraminifers from the uppermost devonian and the dinantian of the rhenish massif (Federal Republic of Germany)

Foraminifers from typical Kulm environments are described from 4 localities at the eastern and northern border of the Rhenish Massif: aQuasiendothyra fauna of uppermost Devonian age (Famennian); a Chernyshinellinae fauna of the lower Dinantian Cf1 Zone (middle Tournaisian); upper Dinantian foraminifers from the Cf4δ to Cf6γ Zones (Middle and Upper Viséan). The foraminifer assemblages of the Cf6 Zone (V3b + c), in theGoniatites crenistria schmidtianus toNeoglyphioceras spirale Subzones, seem to be variegated in Germany and Belgium, but they are definitively poorer than contemporaneous faunes in the British Isles and the Russian Platform.     

Diploids in Microsporum gypseum

The paper studies diploids in dermatophyteMicrosporum gypseum. They were isolated as the more rapidly growing sectors from heterokaryons on minimal medium. They are characterized by their wild morphology, conidiation and growth rate, and they are prototrophic. In their genome they contain all the markers present in both mutant components.