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1.
Regarding the estimation of the energy concentration or digestibility of herb-dominated forage and plant samples from winter pastures, it could be expected that the estimation is only reliable when in vitro methods with rumen fluid as inoculum (= gas production techniques) are used. For the verification of this thesis based on logical reflections, an in vitro-method with rumen fluid added as inoculum, as well as chemical, and enzymatic methods were applied under consideration of existing estimating functions. As a possible reason for the observed divergence of the methods, effects of fungal infections or, respectively, secondary compounds in herbs are discussed. At the present state of knowledge, it is adequate to estimate the energy concentration in vitro by gas tests, as far as fattening types like suckler cows and beef cattle are concerned, maybe in contrast to the forage evaluation for dairy cows. 相似文献
2.
Bérénice Agnola Stéphane Boury Claudie Monot Anne Quillévéré Yves Hervé Drissa Silué 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(5):471-478
A rapid resistance/susceptibility test for Peronospora parasitica (downy mildew) was established by inoculating leaf-disks of four Brassica oleracea accessions. Several conditions were tested: disk disinfection or not, agar medium with or without nutrients and with 50 or 100 ppm of benzimidazole. Using disinfected disks placed on agar (no nutrient and benzimidazole at 50 or 100 ppm), the responses of leaf-disks to four isolates were similar to those obtained using the classical cotyledon test, whereas undesired contaminations occurred in all other conditions. The possible effect of the particular leaf used for obtaining the disks was also studied. In each incompatible interaction tested, disks were resistant whatever the leaf used. In compatible interactions, susceptible phenotypes were observed on disks derived from the six lowest leaves, but disks from upper leaves were resistant. The genetic basis of resistance in a F1 hybrid broccoli was assessed, by testing six isolates on an F2 population derived from this hybrid. The cotyledon test only allows inoculation of two isolates per seedling, whereas many isolates can be tested on each plant by using leaf-disks. The segregation of the resistance to each of the six isolates was analysed: two dominant genes (tightly linked) control resistance to all isolates (one to five isolates; the other to only one isolate). 相似文献
3.
The distribution of woody vegetation was studied in forest edges and hedgerows in a 28 km2 southern Swedish agricultural area, characterised by species-rich edge zones. The occurrence of 21 selected woody species (taxa) was related to differences in both edge structure and landscape structure. All the species studied were represented in both edge types, but a higher frequency of animal-dispersed species was found in hedgerows.Animal dispersed species were more affected by edge width and density than wind dispersed species. A higher number of wind-dispersed species were more frequent in forest edges, in hedgerows near to forest, or with a high proportion of forest within 500 m. A clear relationship was found between the number of physically connected elements in hedgerow networks and increasing frequency of occurrence for Corylus avellana, Crataegus spp., Euonymus europaeus, and Quercus robur; which indicate the ecological significance of connectedness for certain animal dispersed species. The study supports the general principle that woody species distribution and landscape structure are linked in a positive feedback loop. The results match findings from studies in other countries and are interpreted in the context of landscape processes and the ecological characteristics of woody plant species. We emphasise the importance of understanding dispersal mechanisms of woody species for the design and improvement of edge habitats in agricultural landscapes. 相似文献
4.
5.
E. v. c. 《European Journal of Forest Research》1868,12(1):303-303
Ohne Zusammenfassung 相似文献
6.
Ohne Zusammenfassung 相似文献
7.
Q. v. Leo 《European Journal of Forest Research》1867,11(1):390-393
Ohne Zusammenfassung 相似文献
8.
9.
M. v. Cotta M. v. Cotta Mördes v. Pannewib Robert Rühn Paur v. Stelzl v. Deltheim Schulze Q. v. Mikleben Lreiherr v. Lflanteuffel Lreiherr v. Berg Qeitel M. Lreiherr v. Berg v. Michael H. C. Bär Baer A. Chieriod Berger Rettftadt Gekner Wlrici Lreiherr v. Schmerzing Sprenger Pommrich v. Strune Matufchka v. E. Q. Brunft Rnaudt Mördlinger Rnipping v. Mangenheim C. A. Baum L. Mehlborn G. v. Stieglik H. v. Biegefar C. Grebe v.n Baumbach Braun R. Blohmer 《European Journal of Forest Research》1865,9(1):322-324
Ohne Zusammenfassung
f. f?chf. Dberforftmeifter.
f. bahr. Regierungs- und Forftrath von Mürzburg.
f. preuk. Dberforftmeifter aus Breslau.
f. f?chf. Dberforftmeifter.
f. bahr. Regierungs- und Forftrath von Augsburg.
f. bahr. Regierungs- und Forftrath aus Regensburg.
Dberj?germeifter von Braunfchweig.
f. bahr. Regierungs- und Forftrath aus München.
f. f?chf. Dberf?rfter.
f. f?chf. Dberforftmeifter.
f. f?chf. Dberforftrath.
herz. braunfchweig. Forftmeifter von Blanfenburg.
Direftor der fürftlich Cfterhazh’fchen Herrfchaft Spoly Parsto.
fürftl. fondershauf. Dberfortmeifter.
f. bahr. Redierf?rfter don Schmarzenbach.
f. preuk. Dberf?rfter.
f. f. Forftrath aus Brekburg.
f. preuk. Dberf?rfter von Altruppin.
f. hann?v. Forftmeifter von Rienburg.
Forftmeifter in preuk. Schleften.
f. preuk. Dberforftmeifter von Berlin.
herz. aftenburg. Dberfortmeifter.
f. preuk. Dberf?rfter.
f. f?chf. Dberf?rfter.
f. ruff. Forftfomiff?r aus Marfchau.
f. preuk. Forftinfpeftor.
f. f?chf. Forftinfpeftor.
grokh. meimar. Forftinfpeftor von Martfuhl.
f. mürttb. Dberf?rfter und Brofeffor aus Hohenheim.
f. hannov. Forftmeifter aus Hammeln.
Dberforftmeifter aus Sotha.
herz. altenburg. Dberf?rfter aus Hummelshain.
herz. altenburg. Revierf?rfter aus Milchwig.
herz. altenburg. geheimer Finanzrath und Dberforftmeifter.
herz. altenb. Dberforftmeifter aus Hummelshain.
grokh. f?chf. geheimer Dberforftrath aus Qifenach.
herz. naffau. Dberforftrath aus Miesbaden.
grokh. heff. Dberforftfefret?r aus Darmftadt.
f. f?chf. Dberforftmeifter. 相似文献
10.
v. Berg 《European Journal of Forest Research》1865,9(1):369-369
Ohne Zusammenfassung 相似文献