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291.
Siriwan D. Martens Ulrich Korn Simone Roscher Bernd Pieper Helmut Schafft Olaf Steinhfel 《Grass and Forage Science》2019,74(2):284-296
Eleven laboratory‐scale trials were undertaken in different years where ryegrass (Lolium perenne L.) or lucerne (Medicago sativa L.) were ensiled with different concentrations of tannin extracts (quebracho, Schinopsis balansae Engl., mimosa, Acacia mearnsii DE WILD.), and the effects on protein degradation were assessed. The dry‐matter (DM) content in grass silages ranged between 186 and 469 g/kg and in lucerne silages between 187 and 503 g/kg. Tannin extract, either quebracho or mimosa, was applied at 0–30 g/kg forage DM. Commercial additives such as Lactobacillus plantarum, formic acid or hexamine + NaNO2 were applied in two of the grass trials and in six of the lucerne trials. Eight of the trials incorporated a maximum ensiling duration of 90 or 180 days in addition to replicates which were opened and evaluated at earlier stages. All trials included silages which were assessed after at least 49 days of anaerobic storage. The crude protein (CP) fraction A (non‐protein nitrogen, NPN) as proportion of total CP, served as the main indicator for proteolysis. In ryegrass, in general, the level of proteolysis was lower than in lucerne. A correlation of DM content in silages and degree of proteolysis was only evident for ryegrass. In both forages, the degradation of true protein slowed considerably after 24 days of ensiling. True protein was conserved most with the highest level of tannin extract addition. However, in lucerne, the combination of formate with lactobacilli was equally effective up to 330 g DM/kg, and deamination was further inhibited by formic acid compared to tannin extracts. 相似文献
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Bernd Krock Urban Tillmann éric Potvin Hae Jin Jeong Wolfgang Drebing Jane Kilcoyne Ahmed Al-Jorani Michael J. Twiner Qun G?thel Matthias K?ck 《Marine drugs》2015,13(11):6687-6702
Two strains of Azadinium poporum, one from the Korean West coast and the other from the North Sea, were mass cultured for isolation of new azaspiracids. Approximately 0.9 mg of pure AZA-36 (1) and 1.3 mg of pure AZA-37 (2) were isolated from the Korean (870 L) and North Sea (120 L) strains, respectively. The structures were determined to be 3-hydroxy-8-methyl-39-demethyl-azaspiracid-1 (1) and 3-hydroxy-7,8-dihydro-39-demethyl-azaspiracid-1 (2) by 1H- and 13C-NMR. Using the Jurkat T lymphocyte cell toxicity assay, (1) and (2) were found to be 6- and 3-fold less toxic than AZA-1, respectively. 相似文献
296.
Menegat Alexander Bailly Geraldine C. Aponte Raphael Heinrich Gregor M. T. Sievernich Bernd Gerhards Roland 《植物病害和植物保护杂志》2016,123(4):145-153
Journal of Plant Diseases and Protection - Recently, the acetohydroxyacid synthase (AHAS) amino acid substitution Asp376Glu was detected in a Lolium perenne population originating in France. This... 相似文献
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Wanchun Zhao Lili Qi Xiang Gao Gaisheng Zhang Jian Dong Qijiao Chen Bernd Friebe Bikram S. Gill 《Euphytica》2010,175(3):343-350
Dasypyrum villosum (L.) Candargy is a diploid, wild relative of bread wheat (Triticum aestivum L.). Previous studies showed that D. villosum chromosome 1V has genes that encode seed storage proteins that may be used to enhance the grain quality of bread wheat. As
a first step in genetic transfer, the present study was initiated to develop compensating Robertsonian translocations involving
wheat chromosome 1D and D. villosum chromosome 1V and to analyze their effects on grain quality. A monosomic 1D stock was crossed with the disomic addition stock
DA1V#3 and the double monosomic plants (20″ + 1D′ + 1V#3′) were self pollinated. Two co-dominant STS markers (BE499250 and
BE591682) polymorphic for the short arm of 1V#3S and two dominant STS markers (BE518358 and BE585781) polymorphic for the
long arm of 1V#3L were developed to screen a large number of progeny to identify plants that had only the 1V#3S or 1V#3L arms.
Five compensating Robertsonian heterozygous translocations, two (plants #56 and #83) for the short arm (T1DL·1V#3S) and three
(plants #7, #123, and #208) for the long arm (T1DS·1V#3L) were identified from 282 F2 plants and confirmed by genomic in situ hybridization and C-banding analyses. Two homozygous translocations T1DL·1V#3S (plants
#14 and #39) were identified from 52 F3 plants derived from F2 plant #83. Four homozygous translocations T1DS·1V#3L (plants #3, #22, #29, and #30) were identified from 68 F3 plants derived from F2 plant #208. The homozygous translocation T1DL·1V#3S had a significantly higher (37.4 ml) and T1DS·1V#3L had significantly
lower (10 ml) Zeleny sedimentation values compared to Chinese Spring wheat (30.7 ml). Our results showed that 1V#3S increased
gluten strength and enhanced wheat quality, but 1V#3L decreased gluten strength and did not enhance wheat quality. 相似文献
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Marc Marx Franz Buegger Bernd Marschner Jean Charles Munch 《Soil biology & biochemistry》2007,39(12):3043-3055
A deeper understanding of the contribution of carbon (C) released by plant roots (rhizodeposition) to soil organic matter (SOM) can help to increase our knowledge of global C-cycling. These insights can eventually lead to sustainable management of SOM especially in agricultural systems. This study was conducted to determine the fate of 13C labelled rhizodeposit-C of maize and wheat plants. They were grown in a greenhouse in permeable nylon bags filled with upper soil material from two agricultural soils of the same location, but with different crop yields. The bags were placed into pots, which were also filled with soil surrounding the bags. Soil inside the bags was considered as rhizosphere soil, wheras the one outside the bags represented bulk soil. The contributions of rhizodeposits to water extractable organic carbon (WEOC), microbial biomass-C (MB-C), CO2-C evolution, and total organic carbon (Corg) were investigated during a 7-week growing period. The WEOC, MB-C, CO2-C, Corg contents and the respective δ13C values were determined regularly, and a newly developed method for determining δ13C values in soil extracts was applied.In both soils, regardless of crop yield potential, significant incorporation of rhizodeposition-derived C was observed in the MB-C, CO2-C, and Corg pool, but not in the WEOC. The pattern of C incorporation into the different pools was the same for both soils with both plants, and rhizodeposit-derived C was recovered in the order MB-C<Corg<CO2-C. This showed that rhizodeposits were mainly respired, but since Corg was the second largest pool of the overall balances, they were also stabilized in the soils at least in the short term. It is suggested that the increased SOM mineralization observed in this study (positive priming effects) was probably induced by C exchange processes between the soil matrix and soluble rhizodeposits. Moreover, soluble rhizodeposit-C was detected in MB-C and CO2-C evolved outside the direct root zone, showing the availability of these C-components in the bulk soil. 相似文献