Nitrogen yield and nitrogen fixation of winter faba beans

Introducing autumn-sown legumes into Central European farming systems could be beneficial for addressing two challenges for European agriculture, i.e., the substantial deficit of protein sources for livestock and expected changes in agroclimatic conditions. Therefore, a two-year field experiment was conucted under Pannonian climate conditions in eastern Austria to assess nitrogen (N) yield and N fixation of several winter faba bean varieties from different European countries as compared to a spring faba bean. Winter wheat was used as a reference crop for estimating atmospheric N fixation. Winter faba beans were susceptible to frost damage especially in the harder of the two winters. Winter faba bean varieties could not achieve a higher grain yield and a higher grain N yield than the spring faba bean but had a higher grain N concentration (except for one variety). Grain yield and grain N yield of faba beans were severely impaired by drought in one year (with a mean of varieties of 8.3 g N m^?2, winter wheat: 6.4 g N m^?2); in the other year, grain N yield of faba beans considerably surpassed that of winter wheat (with a mean of varieties of 21.5 g N m^?2, winter wheat: 8.8 g N m^?2). After harvest, faba beans left higher nitrate residues in the soil, especially in the subsoil, and higher amounts of N in above-ground residues compared to winter wheat. Faba beans showed high N fixation under optimum conditions (with a mean of varieties of 21.9 g N m^?2) whereas drought considerably impaired N fixation (with a mean of varieties of 6.3 g N m^?2; with no differences between autumn- and spring-sown faba beans). In conclusion, growing winter faba bean varieties in eastern Austria did not result in higher grain yield, grain N yield, and N fixation compared to growing a spring faba bean.     

Impact of Pea necrotic yellow dwarf virus (PNYDV) on nodulation,N2 fixation and yield in faba bean (Vicia faba,L.)

Journal of Plant Diseases and Protection - Pea necrotic yellow dwarf virus (PNYDV) is a novel nanovirus in Europe, affecting various grain legumes. The impact of PNYDV on nodulation, symbiotic N2...     

Identification of rhizomania-infected soil in Europe able to overcome <Emphasis Type="Italic">Rz1</Emphasis> resistance in sugar beet and comparison with other resistance-breaking soils from different geographic origins

Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is vectored by Polymyxa betae. The disease can only be controlled by growing partially resistant sugar beets, which quantitatively reduce virus replication and spread. None of the known major resistance genes (Rz1, Rz2, Rz3), alone or in combination, are able to prevent BNYVV infection entirely. Here we report for the first time the identification of a Spanish soil, containing an A-type BNYVV with RNA 1-4, displaying Rz1 resistance-breaking abilities comparable to soils from the USA and to those from France containing the French (Pithiviers) P-type BNYVV with RNA 5. A resistance test with several soil samples vs. different sugar beet cultivars was conducted under standardised conditions. Sugar beets were analysed after 12 weeks of greenhouse cultivation for taproot weight, BNYVV and relative P. betae content. The soil samples from Spain, France and the USA produced high virus contents and strong rhizomania symptoms in Rz1 plants, indicative of resistance-breaking abilities. In addition, all resistance-breaking soil samples produced detectable virus concentrations in plant lateral roots of the Rz1 + Rz2 cultivar, and plants grown in the Spanish soil sample also had reduced taproot weight and displayed severe rhizomania disease symptoms. Additionally, the main pathogenicity factor P25, responsible for the formation of BNYVV symptoms, showed high sequence variability in the amino acid tetrad at position 67–70. The results suggest the geographically independent selection of BNYVV resistance-breaking isolates following the uniform cultivation of Rz1-containing sugar beet cultivars.     

Über das Auftreten des Dickmaulrüsslers Otiorrhynchus ovatus L. als Schädling der Erdbeeren (Fragaria)

Zusammenfassung und Schlußbetrachtung Otiorrhynchus ovatus L. ist in Deutschland fast ausschließlich als Forstschädling beschrieben worden. Erheblicher Schaden an Erdbeeren wurde bisher namentlich aus Nordamerika bekannt. Der genannte Rüßler vergrößert die Zahl der vermutlich infolge veränderter ökologischer Verhältnisse während der letzten Jahre in Deutschland aufgetretenen Schadinsekten, soweit es die Erdbeerkultur betrifft. Die Art ist polyphag; doch kommt ihr Schaden nur in mehrjährig perennierenden Kulturanlagen infolge der ungestörten Entwicklungsmöglichkeit zur vollen Auswirkung.Im Gebiet von Strehla wurde sowohl im Jahre 1946 als auch 1949 durch die Fraßtätigkeit der Larven ca. 1/5 der gesamten Anbaufläche total vernichtet.Erhöhte Aufmerksamkeit ist für die gefährdeten Kulturen geboten. Erneutes Auftreten des Käfers nach zweijähriger Pause in dreijähriger Anbaufläche des beschriebenen Befallsgebietes würde die Annahme festigen, daß die Generationsdauer im vorliegenden Falle dreijährig ist. Es wurde vorgesehen, durch laufende Bodenuntersuchungen in den gefährdeten Kulturen die Larven im ersten Entwicklungsstadium festzustellen. Gegebenenfalls soll durch Züchtung in der Gefangenschaft zur Klärung des Entwicklungszyklus beigetragen werden.Die Bekämpfung bleibt, wenn infolge unzureichender Vorbeugungsmaßnahmen totaler Schaden eingetreten ist, im wesentlichen darauf beschränkt, durch tiefes Umpflügen der stark befallenen Kulturen, noch bevor die ersten Käfer erscheinen, einen möglichst großen Teil Larven und Puppen auf mechanische Weise zu vernichten. Zur Erkenntnis, wieweit DDT-Präparate und evtl. auch geruchlose Hexa-Mittel zur Bekämpfung brauchbar sind, bedarf es noch planmäßiger Versuche im Freiland.Zukünftige Nachforschungen, wozu sachdienliche Beobachtungen und Mitteilungen aus anderer Gegend sehr erwünscht sind, sollen Aufschluß darüber gehen, ob der Käfer weiterhin als Erdbeerschädling auftritt, oder ob das Massenvorkommen in den Jahren 1946 und 1949 als eine auf das Gebiet von Strehla beschränkte Kalamität anzusehen ist.     

Using otolith microchemical analysis to investigate the importance of brackish bays for pike (Esox lucius Linnaeus, 1758) reproduction in the southern Baltic Sea

The brackish Baltic Sea is inhabited by several primary freshwater fish species. The pike (Esox lucius) is the largest of these species and acts as the top predator in the marine food web of the Baltic Sea. Prior studies have shown the importance of brackish bays as spawning grounds for the Baltic Sea pike. To identify the spawning habitat of the pike population around the island of Rügen (southern Baltic Sea)—either freshwater streams flowing into the Baltic or brackish lagoons of the Baltic—we used the ICPMS method to quantify the strontium to calcium (Sr:Ca) ratios in sagittal otoliths of 79 adult pike. In total, only six per cent (n = 5) of the analysed Baltic Sea individuals were classified as being of freshwater origin. Ninety‐four per cent (n = 74) of analysed pike were classified as having hatched in brackish water. Compared to previous studies on Baltic Sea pike, our sample shows a high proportion of pike that is of brackish origin: this highlights the adaptive capacity of this species with regard to its ability to reproduce in different salinities. Our data highlight the importance of brackish bays for pike reproduction in the southern Baltic Sea, even if pike live on the upper limit of their salinity tolerance in this area. This is an important finding considering decreases in commercial catches in the last 30 years indicating a population decline supposedly related to recruitment failures.     

Zur bildlichen Darstellung der gemeinsamen Sehnenscheide des M. flexor hallucis longus und des M, tibialis caudalis beim Pferd

The possibilities for imaging soft tissue structures, especially fluid-filled cavities such as articulations, bursae or tendon sheaths, have been improved markedly by sonography in recent years. Ultrasonic examinations were performed on the common tendon sheath of the musculus flexor hallucis longus and the musculus tibialis caudalis, from the medioplantar aspect of the tarsus, in 12 sound adult draft- and warm blood horses, and in 5 animals with a distended common sheath. The diagnostic precision of the sonographic examination of the tendon sheath is excellent and is superior to conventional radiography. A nuclear magnetic resonance tomogram of an isolated equine tarsus is presented for comparison method.     

Seasonal variations in location and population structure of endophytes in buds of Scots pine

We studied the location and distribution of a bacterial isolate, a Mycobacterium sp., in buds of Scots pine (Pinus sylvestris L.). Using a probe specific for the 16S rRNA of the Mycobacterium sp., the bacterium was found by in situ hybridization in the meristematic tissues of 40% of all bud samples examined. Because we had previously found other bacterial and fungal endophytes in the meristematic tissues of Scots pine buds, we studied their occurrence in buds during shoot development and dormancy. Using probes targeted to the 16S or 18S rRNA of the endophytes Mycobacterium sp., Methylobacterium spp., Pseudomonas spp. and Rhodotorula minuta, endophytes were found in association with growing tissues, with Methylobacterium spp. being the dominant species. Endophytes were detected in abundance before elongation or differentiation of a bud, but once a tissue was fully developed, endophytes were no longer detected. Metabolic activity of the endophytes was suppressed at the onset of, and during, dormancy of Scots pine, but recovered before the following growing season.