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41.
Chantal?Le Marié Norbert?Kirchgessner Patrick?Flütsch Johannes?Pfeifer Achim?Walter Andreas?HundEmail author 《Plant methods》2016,12(1):40
Background
Phenotyping of genotype-by-environment interactions in the root-zone is of major importance for crop improvement as the spatial distribution of a plant’s root system is crucial for a plant to access water and nutrient resources of the soil. However, so far it is unclear to what extent genetic variations in root system responses to spatially varying soil resources can be utilized for breeding applications. Among others, one limiting factor is the absence of phenotyping platforms allowing the analysis of such interactions.Results
We developed a system that is able to (a) monitor root and shoot growth synchronously, (b) investigate their dynamic responses and (c) analyse the effect of heterogeneous N distribution to parts of the root system in a split-nutrient setup with a throughput (200 individual maize plants at once) sufficient for mapping of quantitative trait loci or for screens of multiple environmental factors. In a test trial, 24 maize genotypes were grown under split nitrogen conditions and the response of shoot and root growth was investigated. An almost double elongation rate of crown and lateral roots was observed under high N for all genotypes. The intensity of genotype-specific responses varied strongly. For example, elongation of crown roots differed almost two times between the fastest and slowest growing genotype. A stronger selective root placement in the high-N compartment was related to an increased shoot development indicating that early vigour might be related to a more intense foraging behaviour.Conclusion
To our knowledge, RADIX is the only system currently existing which allows studying the differential response of crown roots to split-nutrient application to quantify foraging behaviour in genome mapping or selection experiments. In doing so, changes in root and shoot development and the connection to plant performance can be investigated.42.
Jürgen Scherkenbeck Hubert Dyker Daniel Gondol Achim Harder Andrew Plant Felix Reichel 《Pest management science》1999,55(4):457-461
A mono-proline analogue of the potent anthelmintic cyclooctadepsipeptide PF1022A has been synthesized. NMR studies in combination with molecular dynamics simulations demonstrate that the confirmation of this analogue is both rigidified and distorted compared with the asymmetric conformation of PF1022A. The backbone conformation is significant with respect to anthelmintic activity. © 1999 Society of Chemical Industry 相似文献
43.
Amir Abbas Bazyar Lakeh Hamid Farahmand Werner Kloas Alireza Mirvaghefi Achim Trubiroha Brian C. Peterson Sven Wuertz 《Aquaculture International》2016,24(1):11-21
Juvenile rainbow trout (Oncorhynchus mykiss) were passively immunized by intraperitoneal immunization against somatostatin-14 (SS-14) using an antibody originating from egg-laying chicken (Gallus domesticus). Fish were immunized weekly (0, 7, 14, 21, 28, 35 days) with chicken egg yolk-derived immunoglobulin (IgY) against SS-14 (1:25 IgY, 5 mg mL?1), and growth performance, feed utilization as well as plasma concentrations and mRNA levels of growth hormone (GH) and insulin-like growth factor I (IGF-I) were compared to the control group that received placebo immunization with PBS. Passive immunization significantly increased weight gain of treated fish (67.7 ± 7.4 g) compared to the control group (40.1 ± 2.0 g) after 35 days (p < 0.05). Feed conversion ratio (FCR) was significantly improved in the immunized fish (0.7 ± 0.08) compared to control group (1.2 ± 0.06) (p < 0.05). The concentrations of GH and IGF-I in the blood plasma showed no significant differences between the fish treated with anti-SS-14 and those of control during the treatment (p > 0.05). In both groups, GH levels decreased over the 35 days of the experiment (p < 0.05). However, IGF-I level during the period of treatment remained unchanged in both control and immunized fish with the anti-SS-14. Similarly, no changes were observed in pituitary GH and liver IGF-I mRNA levels between treatment and control at each sampling time (p > 0.05). There was no indication of a cumulative, long-lasting effect of repeated immunization on GH or IGF-I plasma concentrations or mRNA expression. The present study shows that a passive immunization of rainbow trout against SS-14 using a chicken egg yolk-derived SS-14 antibody could increase growth rate and improved FCR. 相似文献
44.
Böcker U Ofstad R Bertram HC Egelandsdal B Kohler A 《Journal of agricultural and food chemistry》2006,54(18):6733-6740
FT-IR microspectroscopy and light microscopy were used to investigate pork muscle musculus semitendinosus samples, taken from three animals, that were subjected to brine salting at different concentrations (0.9, 3, 6, and 9% NaCl). Differences in spectral characteristics and in microstructure were observed in meat from animals differing in initial pH and varying salt concentrations. The FT-IR data displayed changes in the amide I region from 1700 to 1600 cm(-1). This spectral range was analyzed by principal component analysis (PCA) and partial least-squares regression (PLSR). These methods revealed correlations between the spectral data and the different animals, salt content, moisture content, pH value, and myofiber diameter. A shrinking share of alpha-helical components was related to an increase in salt concentration in the muscle. At the same time, a greater share in nonhydrogenated C=O groups (1668 cm(-1)) was related to an increase in salt concentration in the meat. The share of aggregated beta-strands differed with respect to the different animals but was not influenced by salt concentration. The meat at higher pHs (>6) had less aggregated beta-strands than that at lower pHs (5.6-5.7). It could be demonstrated that simultaneous with changes in microstructure, pH value, salt, and moisture content were alterations in the protein amide I region as measured by FT-IR microspectroscopy, revealing a relationship between these biophysical and chemical parameters and secondary protein structure attributes. 相似文献
45.
John Moore Alexis Achim Andrew Lyon Shaun Mochan Barry Gardiner 《Forest Ecology and Management》2009,258(7):1174-1180
The effects of early re-spacing on the physical and mechanical properties of Sitka spruce (Picea sitchensis [Bong.] Carr.) structural-dimensioned timber were studied using material from a fully replicated 57-year-old trial located in Northern Ireland, which had been thinned at age 11 years. Basic density, distortion (spring, twist and bow), modulus of elasticity (MOE) and modulus of rupture (MOR) in bending of structural timber from four different re-spacing treatments (1.83 m × 3.66 m, 3.66 m × 3.66 m, 3.66 m × 5.49 m and 5.49 m × 5.49 m) were compared with those of timber from a control (1.83 m × 1.83 m). Re-spacing intensity had a significant effect on both modulus of elasticity (p = 0.006) and modulus of rupture (p = 0.009), but not on basic density (p = 0.379) or distortion (p > 0.200). Timber from the two widest re-spacing treatments failed to meet the requirements for the C14 strength class, while timber from the control met the requirements for the C16 strength class. Both MOE and MOR were significantly and negatively associated with knot size and frequency, which in turn increased with re-spacing intensity. Overall, re-spacing intensity only explained approximately 10% of the total amount of variation in both MOE and MOR, with most of the variation due to inter- and intra-tree differences within a treatment. Based on these results, re-spacing of Sitka spruce to a residual stand density of less than 900 trees/ha (3.33 m × 3.33 m) is not recommended if the goal of management is to produce C16 structural timber. 相似文献
46.
Improved understanding of tree-growth responses to climate is needed to model and predict forest ecosystem responses to current and future climatic variability. We applied dendroclimatological techniques to assess the effects of inter-annual climate variations on radial growth of high-elevation conifers in the central Hengduan Mountains, southwestern China. Eight tree-ring width chronologies of the major tree genera Abies and Picea that are aligned along an elevation gradient from 3200 to 4200 m a.s.l. were developed. Correlation and principal component analyses for the eight chronologies identified three groups of sites, representing different patterns of growth–climate relationships. Correlation and redundancy analyses with regional climate data revealed that radial growth of fir growing at high-elevation sites is enhanced by normal or warm summer temperatures (June and July) during the current growing season. In addition, radial growth of trees growing from high to middle elevations is sensitive to low temperatures during winter season. At low-elevation sites, trees display low sensitivity to temperature variation. However spring moisture availability becomes crucial for radial growth regardless of tree species. High- to middle-elevation conifers in the central Hengduan Mountains may benefit from the current climate warming, especially from rising winter temperatures. 相似文献
47.
Whereas in former times horses were reserved primarily for people involved in
agriculture, elite equestrians or the military, nowadays equestrian sport has become an
activity for people with a wide variety of backgrounds. However, as more and more people
become involved with equestrian sport today, the knowledge concerning animal husbandry in
general is diminishing due to an alienation from agricultural themes in modern societies.
As a consequence, this development affects both riding ability and the appraisal of
horses, especially with respect to the purchase of horses. In order to analyse which
factors influence purchase decisions in the horse market in conjunction with equestrian
experience, 739 horse riders were surveyed on their purchase behaviour in this study.
Using cluster analysis, a typology was generated that provides a differentiated picture of
the preferences of the various rider groups. Three clusters were distinguished: the
“amateurs”, the “experienced” and the “experts”. Taking personal horse riding proficiency
into account, it could be concluded that especially the “amateur” group required objective
criteria for the evaluation of a horse they are considering purchasing. Alongside
“measureable” qualities, such as previous showing success or the level of training of the
horse, also other attributes such as the simple handling of the horse should be taken into
consideration. As particularly the “amateur” group in equestrian sport is increasing in
numbers, it is therefore advisable when preparing a horse for sale to align oneself to the
needs of this customer segment in order to ensure an effective and targeted marketing of
horses. 相似文献
48.
K Hennig R Verkerk G Bonnema M Dekker 《Journal of agricultural and food chemistry》2012,60(32):7859-7865
Kinetic modeling was used as a tool to quantitatively estimate glucosinolate thermal degradation rate constants. Literature shows that thermal degradation rates differ in different vegetables. Well-characterized plant material, leaves of broccoli and Chinese kale plants grown in two seasons, was used in the study. It was shown that a first-order reaction is appropriate to model glucosinolate degradation independent from the season. No difference in degradation rate constants of structurally identical glucosinolates was found between broccoli and Chinese kale leaves when grown in the same season. However, glucosinolate degradation rate constants were highly affected by the season (20-80% increase in spring compared to autumn). These results suggest that differences in glucosinolate degradation rate constants can be due to variation in environmental as well as genetic factors. Furthermore, a methodology to estimate rate constants rapidly is provided to enable the analysis of high sample numbers for future studies. 相似文献
49.
Jaine H. H. L. de Oliveira Mirna H. R. Seleghim Christoph Timm Achim Grube Matthias K?ck Gislene G.F. Nascimento Ana Claudia T. Martins Elissa G. O. Silva Ana Olívia de Souza Paulo R. R. Minarini Fabio C. S. Galetti Célio L. Silva Eduardo Hajdu Roberto G. S. Berlinck 《Marine drugs》2006,4(1):1-8
Cyclostellettamines A – F (1 – 6) isolated from the sponge Pachychalina sp. and cyclostellettamines G - I, K and L (7 – 11) obtained by synthesis were evaluated in bioassays of antimicrobial activity against susceptible and antibiotic-resistant Staphylococcus aureus, Pseudomonas aeruginosa and antibiotic-susceptible Escherichia coli and Candida albicans, as well as in antimycobacterial activity against Mycobacterium tuberculosis H37Rv bioassays. The results obtained indicated that cyclostellettamines display different antimicrobial activity depending on the alkyl-chain size, suggesting that, if a mechanism-of action is implied, it is dependent on the distance between the two pyridinium moieties of cyclostellettamines. 相似文献
50.
0.2% L-lysine with an atom-% 15N-excess (15N') of 48% were given per day through a throat probe in an experiment to three colostomised laying hybrids in addition to a pelleted ration of 120 g per animal and day. In the following 4 days unlabelled L-lysine was given. As the labelled lysine was given three times a day, the development of 15N'-excretion could be pursued. 80 minutes after the 15N'-lysine dose a distinct atom-% 15N' could be detected in urine. 6 hours after the 15N'-application we rediscovered 2.9% (hen 1), 4.2% (hen 2) and 2.7% (hen 3) of the applied 15N'-amount in urine. 8 days after the beginning of the experiment the excretion of 15N' in urine averaged 17.5% of the consumed 15N'-amount. 44% of the nitrogen in the ration, however, was excreted in urine. The results showed that the lysine-N is excreted to a considerably lower extent in urine than the nitrogen in the remaining ration. 相似文献