Geo‐Pedogenese mariner Rohmarschen Spiekeroogs

Geo‐pedogenesis of Salic Fluvisols on the North Sea island of Spiekeroog Although the mainland's Salic Fluvisols of the southern North Sea coast are rich in carbonate, those of the adjacent island Spiekeroog are not. Thus, the aim of this study was to investigate the Salic Fluvisols of Spiekeroog in comparison to those of the mainland and to find out the reasons for the lack of carbonate, which was supposed to be an interaction between sedimentation and sulfur dynamics. The vegetation, many physical and chemical properties (e.g. pH, C_org, salinity, Fe_od, exchangeable cations, CEC) of the Spiekeroog Fluvisols are similar to those of the mainland. However, the Spiekeroog soil profiles extended over the marsh sediments, and the sand sediments below and they contained more silt and less clay and carbonate (0.3 – 34.5 g kg^–1) than the soils of the mainland. A survey proved carbonate‐free areas. The relatively moderate S dynamics showed a spatial and temporal stabile SO₄‐S‐fraction (0.3 – 0.6 mg g^–1), a fairly stabile HNO₃‐HCl‐S fraction (1.5 – 2.9 mg g^–1), but a variable HCl‐S fraction. The vertical Cs‐137 distribution showed peaks at 3 – 4 and 7 – 8 cm soil depth, indicating sedimentation rates of 0.2 – 0.5 cm a^–1. The results showed that moderate S dynamics lead to carbonate losses which are not compensated because of low sedimentation rates. Consequently, the Spiekeroog Salic Fluvisols will enter the terrestrial phase of soil development without carbonate. Thus, besides the usual pedogenesis of Eutric Fluvisols via Salic and Calcaric Fluvisols, the investigation proved a direct development from Salic to Eutric Fluvisols.     

The potential use of heterosis in Beta vulgaris L. II. Yield performance of pure lines and their hybrids

Summary The yield performance is described of pure lines obtained from doubled monoploids and their corresponding polycross and pair-cross hybrids. The total dry matter yields of fifteen pure lines averaged 60–90% of the yields of the progenitor and control varieties. Seven of the resultant polycross hybrids gave dry matter yields similar to or higher than the progenitor varieties, whilst the remaining hybrids were less productive than their parental lines. In pair-cross hybrids significant reciprocal differences were found in some cases. This was attributed to differences in self-fertility and the degree of self-fertilization in reciprocal crosses. Based on the frequency of offspring with white or coloured roots, self-fertilization frequencies ranging from 14% to 92% were found. It is estimated that in the event of complete cross-fertilization, the yields of certain pair-cross hybrids would have exceeded those of the control varieties by 9–29%.     

Taxonomy and evolution of cultivated plants: Literature review 1977/1978

Summary Important papers on taxonomy and evolution of cultivated plants published in 1977 and 1978 were put together and briefly discussed.

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Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1977/1978

Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1977–1978 wurden zusammengestellt und kurz kommentiert.

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: 1977 1978

, 1977–1978 . .

     

Rasterelektronenmikroskopische Untersuchungen an Samen der GattungAllium L

Zusammenfassung Die Skulpturmerkmale von Samenoberflächen verschiedenerAllium-Arten wurden rasterelektronenmikroskopisch geprüft. Die Untersuchungen bestätigen die große Variabilität dieses Merkmalskomplexes. Die Ausbildung der Testaskulptur-Merkmale in verschiedenen Sektionen der Gattung sowie Probleme der infraspezifischen Variabilität werden diskutiert.

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SEM investigations on seeds of the genusAllium L

Summary The sculpture characters of seed coats of differentAllium species have been examined by means of SEM. The investigations confirm the great variability of this character complex. The characters of the testa sculpture in different sections of the genus as well as problems of infraspecific variability are discussed.

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Allium L. ¶rt;

Allium L. . . .

     

Rasterelektronenmikroskopische Untersuchungen an Samen der GattungAllium L. III.

Zusammenfassung Die Testa-Epidermisskulpturen von weiteren Arten der GattungAllium L. wurden rasterelektronenmikroskopisch untersucht. Dabei konnten die bisherigen Befunde über die sektionsspezifische Ausbildung der Testaskulpturen weitgehend bestätigt werden.Die wenig differenzierten Testaskulpturen der sect.Anguinum G. Don exKoch wurden an weiteren Arten der Gattung nachgewiesen. Die untersuchten Arten der sect.Rhizirideum G. Don exKoch entsprechen in der Mehrzahl den charakteristischen granulösen Skulpturtypen dieser Sektion. Besonderheiten ergeben sich bei einzelnen Arten durch spezielle verrucose Skulpturen bzw. deutlich undulierte Antiklinalwände.Die Testaskulpturen einiger Arten der sect.Cepa (Miller)Prokh. konnten den für diese Sektion typischen Skulpturformen zugeordnet werden.Der einheitliche, verrucose Skulpturtyp der sect.Codonoprasum Reichenb. wurde durch weitere Arten bestätigt. Ebenso zeigen die Arten der sect.Caloscordum (Herb.)Bak. übereinstimmende Testamerkmale.Die untersuchten Sippen der sect.Lophioprason Traub entsprechen in ihrer Testaskulptur dem bisher bekannten Merkmalsspektrum der jeweiligen Artengruppe. Hierbei konnte auch der spezielle verrucose Skulpturtyp derAllium acuminatum-Gruppe an weiteren Arten dieser Gruppe nachgewiesen werden. Granulöse Skulpturformen wurden bei einzelnen Arten der sect.Rhophetoprason Traub und sect.Amerallium Traub gefunden.Die der sect.Allium L. und dem subgen.Melanocrommyum (Webb etBerth.)Rouy gemeinsame Testaform, die durch verrucose Skulpturen sowie eine ausgeprägte Antiklinalwand-Undulation gekennzeichnet ist, wurde durch weitere Arten dieses Verwandtschaftskreises bestätigt. Dabei unterscheidet sich der Undulationstyp der SektionenAllium L. undMegaloprason Wendelbo von den untersuchten Arten anderer Sektionen des subgen.Melanocrommyum (Webb etBerth.)Rouy.

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SEM investigations on seeds of the genusAllium L. III

Summary The structure of the testa epidermis of additional species ofAllium L. have been studied by means of SEM. Results obtained earlier for different sections of the genus could be confirmed:The less differentiated testa structure of sect.Anguinum G. Don exKoch has been observed in further species of this group.Most of the newly examined taxa of sect.Rhizirideum G. Don exKoch correspond to the already known testa types of this section and are characterized by granulate seed coat surfaces. Deviations have been found in some species which possess either a special type of verrucate sculptures or have distinctly undulated anticlinal walls of the testa cells.The earlier described two testa types of sect.Cepa (Mill.)Prokh. could be observed in some additional species of this section, too.Likewise the uniformly verrucate sculptures of sect.Codonoprasum Rchb. have been found in further species and also the taxa of sect.Caloscordum (Herb.)Bak. agree in their testa characters.Earlier described seed coat types for different species groups of sect.Lophioprason Traub could be confirmed, among them the verrucate sculptures of theAllium acuminatum-group. Granulate testa surfaces have been analyzed in several species of sect.Rhophetoprason Traub and sect.Amerallium Traub. The testa type commonly found in sect.Allium as well as in subgen.Melanocrommyum (Webb etBerth.)Rouy and characterized by verrucate sculptures and strong undulation of the anticlinal cell walls could be observed in further species of these infrageneric groups. The undulation pattern of sect.Allium and sect.Megaloprason Wendelbo however differs from that of other sections of subgen.Melanocrommyum (Webb etBerth.)Rouy.

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Allium L. . III.

Allium L. . , - . Anguinum G. Don exKoch . Rhizirideum G. Don exKoch , . . Cepa (Miller)Prokh. . Codonoprasum Reichenb. . Caloscordum (Herb.)Bak. . Lophioprason Traub , . , Allium acuminatum- . Rhophctoprason Traub Amerallium Traub. Allium L. Melanocrommyum (Webb et.Berth.)Rouy, , , . Allium L. Megaloprason Wendelbo Melanocrommyum (Webb etBerth.)Rouy.

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Einige der untersuchten Arten konnten während der gemeinsamen Expeditionen in der Georgischen SSR gesammelt werden, die von Frau Dr.R. K. Beridze, Botanisches Institut der Georgischen Akademie der Wissenschaften, in bewährter Weise organisiert wurden. Dieses ist eine willkommene Gelegenheit, ihr diesen Beitrag anläßlich ihres 70. Geburtstages zu widmen.     

Confirmation of <Emphasis Type="Italic">Peronospora agrimoniae</Emphasis> as a distinct species

Leaves with typical symptoms of downy mildew were found on common agrimony in the Czech Republic in 2014 and 2015 and at several locations in Germany from 2010 to 2014. The causal agent of downy mildew of agrimony was often reported as Peronospora agrimoniae, but sometimes also as P. sparsa. Morphological characteristics of the pathogens found in both countries are in the range of previous works for P. agrimoniae, but also other downy mildews parasitic on Rosaceae, rendering their discrimination based on published observations difficult. For molecular identification sequencing of several loci (nrITS rDNA, cox1 and cox2) was performed. Phylogenetic analyses based on nrITS rDNA clearly separated P. agrimoniae from other Peronospora species infecting Rosaceae. Thus, considering P. agrimoniae as separate species seems justified. Two German specimens were identical to two Czech samples in both nrITS rDNA and cox1 mtDNA sequences, but differed in a single nucleotide substitution in cox2 region. To our knowledge, this is the first verified record of P. agrimoniae on common agrimony in the Czech Republic.     

Comparison of conventional and long-acting oxytetracyclines in prevention of induced Actinobacillus (Haemophilus) pleuropneumoniae infection of growing swine.

These experiments tested the hypothesis that long-acting oxytetracycline (oxytetracycline-LA) was more effective than regular oxytetracycline in preventing porcine pleuropneumonia when administered either 24 or 48 h prior to experimental challenge with virulent strains of Actinobacillus pleuropneumoniae. Two experiments (1 and 2) were conducted using growing pigs (average weight 12-15 kg). Antibiotic treatments were administered once intramuscularly at 20 mg/kg body weight; controls received an equivalent volume of saline. Clinical signs were recorded over seven days, and mortality rates and pathological lesions were analyzed using analysis of variance. Serum oxytetracycline levels were compared 48 and 72 h postinjection. All pigs developed clinical disease following experimental infection. Actinobacillus pleuropneumoniae was recovered from 42% of experiment 1 pigs and all of experiment 2 pigs. The data showed that both oxytetracycline and oxytetracycline-LA given at the same dose protected pigs against experimental infection when given 24 h prior to challenge, and there was no difference between the efficacy of the two drugs in this experiment. When administered 48 h prior to challenge, only oxytetracycline-LA reduced the clinical signs and pathological changes following A. pleuropneumoniae challenge. Between 48 and 72 h postinjection, oxytetracycline-LA blood levels were significantly greater compared to oxytetracycline-treated pigs.