Factors Influencing the Yield Proportions of \u3ci\u3ePlantago lanceolata\u3c/i\u3e L. and \u3ci\u3eTaraxacum officinale\u3c/i\u3e Web. in \u3ci\u3eLolium perenne\u3c/i\u3e L. Swards

Diaspores of Plantago lanceolata and Taraxacum officinale respectively were sown in established Lolium perenne swards to determine the dynamics of their yield proportions during five years. The experimental factors were forb species, variety of the grass species (= early or late flowering), N-fertilization, and sward density. The amount of nitrogen fertilizer had the most important effect on yield proportions of the forb species and also on the total dry-matter (= DM) yield. The single creation of gaps in grass swards before sowing forbs had a lasting positive effect on the Plantago lanceolata and Taraxacum officinale proportions. Peak proportions of Taraxacum officinale in May were reduced when it was accompanied by the early flowering Lolium perenne variety. In contrast to Taraxacum officinale, until 1996 Plantago lanceolata had high yield proportions even when 80 kg N ha-1 a-1 was applied. This situation was not persistent, since the proportions of Plantago lanceolata in plots with high N amounts decreased rapidly in the following years

Suitability of Selenate Containing Silage Additives for the Supply of Beef Cattle

Selenium concentrations in herbage are frequently insufficient (\u3c 100 μg Se/kg dry matter (DM)) to meet the requirements of ruminants. Whereas increasing Se supply by feeding mineral mixtures is a reliable method to prevent Se deficiencies for dairy cows, adequate Se supplementation is more difficult to achieve in extensive systems (McDowell, 1996). A suitable measure could be the addition of Se to herbage before ensiling

Eigenschaften von Mischungen mit perennierenden Leguminosen und Gräsern aus dem Anbau in alternierenden Reihen unter Einbeziehung einer Hochzuckergras-Sorte

Three different perennial legume species (Lotus corniculatus, Medicago sativa, Trifolium pratense) were cultivated in alternate drills with one of three different grasses each. L. corniculatus is known to be rich in tannins, which are supposed to have positive effects on protein digestion of ruminants and methane emissions. One of the grass components was a Lolium perenne cultivar (cv. Aberavon) with increased concentrations of water-soluble carbohydrates (wsc). The influence of this grass variety on forage characteristics in mixtures was tested compared to other grasses (Lolium perenne cv. Gladio and Lolium multiflorum cv. Ligrande). Dry matter yield of different mixtures was determined and concentration of wsc in herbage before ensiling was analysed. Digestibility of organic matter (DOM) in silages was determined encymatically. Aberavon had higher contents of wsc compared to other grasses but there were no differences in DOM of silages caused by the grass cultivar. Mixtures containing Aberavon yielded less dry matter than other grasses. Dry matter yields of mixtures with L. corniculatus were similar or slightly inferior to the yield of the mixtures with M. sativa or T. pratense. Digestibility of silages including L. corniculatus was similar to M. sativa variants and even superior to T. pratense mixtures in single cases

Influence of senescence on the differentiation of the ingredients of grain legume straw as a basis for the calculation of theoretical biogas potentials

Der Einsatz von Getreidekorn oder Mais als Substrat für die Biogasanlage wird durch das Erneuerbare-Energien-Gesetz (EEG) zukünftig schrittweise auf maximal 44 % begrenzt (EEG, 2017, § 39 h). Zusätzlich hierzu wird bei den meisten bestehenden und neuen Anlagen die Festvergütung entfallen, was eine weitere Herausforderung hinsichtlich der Wirtschaftlichkeit von Substraten darstellt. Koppelprodukte aus der Landwirtschaft stellen eine bisher weitestgehend ungenutzte, kostengünstige Alternative dar. Für einen erfolgreichen Einsatz von stroh­artigen und damit lignozellulosereichen Substraten in Biogasanlagen ist es jedoch notwendig, Daten zum Biogaspotential zu generieren. Den bisherigen hauptsäch­lichen Anbaureiz bei Körnerleguminosen stellt der Vorfruchtwert der Kultur dar (Zerhusen-Blecher et al., 2016). Die Nutzung dieses Koppelprodukts in Biogas­anlagen könnte einen zusätzlichen Anbaureiz schaffen und die Wirtschaftlichkeit von Körnerleguminosen verbessern. Um die Auswirkung der zunehmenden Seneszenz auf die Inhaltsstoffe des Strohs bei Körnerleguminosen zu prüfen, wurden jeweils drei Genotypen von Futter­erbsen Pisum sativum L. und Ackerbohnen Vicia faba L. in zwei Jahren, an zwei Standorten in vierfacher Wiederholung zu unterschiedlichen Terminen geerntet und als Stroh oder Strohsilage konserviert. Die Termine sollten die Zeitspanne von einer beginnenden Drusch­reife (BBCH 84 – 89), zur Druschreife (BBCH 89 – 94) und später Druschreife (BBCH 96 – 98) bis hin zur vollständigen Totreife (BBCH 99) abdecken. Die Untersuchung der Inhaltsstoffe umfasste den Rohprotein-, Hemizellulose-, Zellulose- und Ligningehalt nach van Soest. Anhand dieser Inhaltsstoffe wurden theoretische Biogaspotentiale berechnet. Die Untersuchungen ergaben bei beiden Arten eine Abnahme des Rohproteingehalts mit zunehmender Seneszenz. Bei den anderen Inhaltsstoffen gab es Unterschiede zwischen den Arten und Konser­vierungsverfahren. Der Hemizellulosegehalt lag, durch die Silierung abgebaut und zu organischen Säuren umgewandelt, bei den Silagen unterhalb der Gehalte im Stroh, trotz identischem Ausgangsmaterial. Insgesamt wurde eine Zunahme der Gerüstsubstanzen mit fortschreitender Seneszenz festgestellt. Die theoretischen Biogas­potentiale nahmen mit fortschreitender Seneszenz zu oder blieben davon unbeeinflusst. Es wurden Biogasausbeuten von etwa 530 l/kg TM und Methangasausbeuten von etwa 265 l/kg TM berechnet, dies entspricht etwa 75 % der Methangasausbeute von Silomais (Karpenstein-Machan, 2005). Die Sortenunterschiede waren bei den Gasausbeuten der Ackerbohnen gering, daher ist der Strohertrag ein wichtigerer Parameter für die Nutzung als Biogassubstrat. Bei den Ackerbohnen sind die Sorten Fuego und Tiffany zu empfehlen, da hier die Stroherträge gesichert höher waren als die der Sorte Taifun. Bei den Erbsen hatte die Sorte Respect einen höheren Stroh­ertrag und etwas höhere Gasausbeuten als die anderen Sorten, jedoch konnte diese Sorte nicht vollständig geprüft werden, weshalb keine Sortenempfehlung gegeben wird.The use of cereal grains or maize as substrate for the biogas plant will in future be gradually limited to a maximum of 44 % by the Renewable Energy Sources Act (EEG, 2017, § 39 h). In addition, the fixed payment will no longer apply to most existing plants and new plants, which represents a further challenge with regard to the economic efficiency of substrates. Co-products from agriculture represent a so far largely unused, cost-effective alternative. Up to now, the main motivation for growing grain legumes has been the preceding crop value of the crop (Zerhusen-Blecher et al., 2016). The use of this co-product in biogas plants could provide an additional cultivation inducement and improve the profitability of grain legumes. However, for a successful use of straw-like and thus lignocellulose-rich substrates in biogas plants it is necessary to generate data on the biogas potential. In order to test the effect of increasing senescence on straw ingredients in grain legumes, three genotypes each of field peas Pisum sativum L. and field beans Vicia faba L. were harvested at different dates and conserved as straw or straw silage in two years, at two locations with four repetitions. Harvesting dates should cover the period from beginning of threshing maturity (EC 84–89), to threshing maturity (EC 89–94) and later threshing matu­rity (EC 96–98) until complete dead maturity (EC 99). The examina­tion of the ingredients included the crude protein, hemicellulose, cellulose and lignin content accord­ing to van Soest. Based on these ingredients, theoretical biogas potentials were calculated. The investigations showed a decrease of the crude protein content with increas­ing senescence in both species. For the other ingredients, there were differences between the species and preservation methods. The hemicellulose content degraded by ensiling and converted to organic acids was lower in the silages than in the straw, despite the same starting material. Overall, an increase in the structural substances with progressive senescence was observed. The theoretical biogas potentials increased with pro­gressive senescence or remained unaffected by it. Biogas yields of about 530 l/kg DM and methane gas yields of about 265 l/kg DM were calculated, which is about 75 % of the methane gas yield of silage maize (Karpenstein-Machan, 2005). The differences in the gas yields of field bean varieties were small, therefore straw yield as a parameter for use as biogas substrate is more important. For field beans, the varieties Fuego and Tiffany are recommended, since the straw yields were significantly higher than those of the variety Taifun. For peas, the variety Respect had a higher straw yield and slightly higher gas yields than the other varieties, but this variety could not be completely tested, which is why no variety recommendation is given

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements