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排序方式: 共有458条查询结果,搜索用时 15 毫秒
91.
XIEXiao-mei LIAOMin LIUWei-ping SusanneKLOSE 《水稻科学》2004,11(3):140-146
Combined effects on soil microbial activity of nutrient and pesticide management in hybrid rice double annual cropping system were studied. Results of field experiment demonstrated significant changes in soil microbial biomass phospholipid contents, abundance of heterotrophic bacteria and proteolytic bacteria, electron transport system (ETS)/dehydrogenase activity, soil protein contents under different management practices and at various growth stages. Marked depletions in the soil microbial biomass phospholipid contents were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also induced slight changes, and the lowest microbial biomass phospholipid content was found with pesticides application alone. A decline in the bacterial abundance of heterotrophic bacteria and proteolytic bacteria was observed during the continuance of crop growth, while the lowest abundance of heterotrophic bacteria and proteolytic bacteria was found with pesticides application alone, which coincided with the decline of soil microbial biomass. A consistent increase in the electron transport system activity was measured during the different crop growth stages of rice. The use of fertilizers (NPK) alone or combined with pesticides increased it, while a decline was noticed with pesticides application alone as compared with the control. The soil protein content was found to be relatively stable with fertilizers and/or pesticides application at various growth stages in both crops undertaken, but notable changes were detected at different growth stages. 相似文献
92.
Anna M. Johansson Maulik Upadhyay Erling Strandberg Susanne Eriksson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2020,69(1-2):39-46
ABSTRACTThe Swedish Mountain (Fjäll) cattle and the subpopulation Fjällnära originates from northern Sweden. They are differentiated from both traditional and commercial cattle from southern Sweden. We analysed data from the GGP HD150k SNP array and investigated genetic diversity and differences between Fjäll and Fjällnära, and between different groups of Fjällnära. We found that the Fjällnära can be divided into four groups, which are differentiated from each other and from the other Fjäll cattle. We also compared allele frequencies between different groups of Fjäll and Fjällnära for some of the functional SNPs included in the SNP array. Interestingly, the B allele of Beta lactoglobulin has a very high frequency (94%) in the Fjällnära cattle, which is significantly different from the frequency in the Fjäll cattle (60%). Comparing older samples of Fjäll cattle with more recent samples, we found a significant increase in the frequency of the B allele in Fjäll cattle. 相似文献
93.
J. Schittenhelm S. Westphal Susanne Toder E. Wagner 《European Journal of Forest Research》1993,112(1):240-250
Zusammenfassung Die Auswirkungen verschiedener Stre?faktoren auf das antioxidative System wurden in sechsj?hrigen Klonfichten untersucht.
überflutung und Dunkelheit hatten nur geringen Einflu?. Im Gegensatz dazu wirkten sich die Stre?faktoren Trockenheit, K?lte,
Starklicht und sehr hohe Ozonkonzentrationen stark auf das antioxidative System aus. Die Effekte waren jedoch nicht einheitlich,
sondern waren je nach Stre?faktor unterschiedlich. Dies wird als ein Hinweis dafür gewertet, da? die Sch?den bei diesen Stre?faktoren
durch unterschiedliche toxische Sauerstoffspezies entstehen und da? sich die Sch?den unter Freilandbedingungen synergistisch
verst?rken k?nnen.
The antioxidative system of Norway spruce: Effects of different stress factors
Summary The effects of different stress factors on the antioxidative system of 6-year-old Norway spruces of the same clone were examined. Flooding and permanent darkness had only minor effects. On the other hand drought, chilling, intense light, and very high ozone concentrations showed strong but distinct consequences. This indicates that the damages by these stress factors are due to different toxic oxygen species, and that the stress factors could produce synergistic damages under natural field conditions.相似文献
94.
95.
Susanne Riede Carola Lindig Hansjrg Abel Bettina Tonn Johannes Isselstein Gerhard Breves 《Journal of animal physiology and animal nutrition》2019,103(2):436-446
According to climate change scenarios, central Europe may expect extending drought periods during summer. Lower water availability may influence the ruminal digestion of individual forage legume species differently. To test this hypothesis, Lotus corniculatus L. (var. Bull), Medicago lupulina L. (var. Ekola), Medicago falcata L. (wild seeds) and Trifolium repens L. (var. Rivendel) were each grown in parallel lots of control and drought‐stressed monocultures. Rainout shelters (installed in May 2011 on a regrowth after first cut until harvest in mid of June) withheld rainfall of 40 mm in the drought stress treatment. Samples of dried (60°C) and milled (5 mm screen) forage legumes were incubated in a simulation experiment using Rusitec to assess drought effects on parameters for microbial metabolism. Degradability of dry matter and organic matter as well as methane production decreased in incubations with drought‐stressed compared to control variants of legume species. Degradability of crude protein, neutral detergent fibre, acid detergent fibre and residual organic matter including non‐fibre carbohydrates and lipids were affected by interactions between drought stress and species. Significant interactions were also found for ammonia concentrations, molar SCFA proportions and the microbial communities. It is concluded that drought stress for growing forage legumes influences their ruminal degradation and fermentation as well as the ruminal microbial communities of Bacteria and Archaea differently in a legume species‐dependent manner. 相似文献
96.
In order to reduce the loss of quality of freshly harvested strawberries during storage, the effects of different packaging materials were examined with regard to storage time and temperature regime (20°C with relative humidity 75%, 4°C with relative humidity 88%). Strawberry containers (500?g) were used differing in form, alignment and number of ventilation openings, top and material. It was found that a drop in temperature to 4°C preserved the quality of strawberries longer in all packaging variants. Nevertheless, the used packaging material had different effects on the quality parameters. The packaging material made of polypropylene, which was closed with a lid and was equipped only with little ventilation openings, yielded the best results, e.?g. the transpiration losses were strongly reduced, thus favouring the preservation of pulp consistency and colour stability of the fruits. On the other hand, the fresh mass during storage was reduced by the materials polyethylenterephthalat, polyactid and groundwood. The quality loss was less dependent on the material, but more dependent on the number of ventilation openings. The results showed that with increasing numbers of ventilation openings the transpiration losses increased and the consistency and colour stability of the fruits decreased. In this context, a strong reduction of pathogenic infestation in relation to the ventilation openings could not be observed. As such, the loss of freshness was lowest with the packaging material of polypropylene, followed by the polyethylenterephthalat, polyactid and groundwood. Moreover, it was found that the kind of packaging material and the ventilation openings had an effect on the amount of pressure marks and the discharge of cell sap of the strawberries. The uneven ground surface of the materials made of polyethylenterephthalat and polyactid increased the punctual pressure on the strawberry fruits, which led to pressure marks and injuries of the fruit surface. Sharp-edged ventilation openings close to the ground surface of these variants favoured injuries and cell sap discharges of the packaging. 相似文献
97.
98.
Ria Paunonen Riitta Julkunen-Tiitto Riitta Tegelberg Matti Rousi Susanne Heiska 《Industrial Crops and Products》2009,29(2-3):261-268
Willow based herbal products containing salicin and its derivatives can be used to alleviate aches and fevers. To guarantee the high quality of the willow drugs and moderate low cultivation and transportation costs, the willows with high salicylate concentrations are recommended for herbal production. Dark-leaved willow (Salix myrsinifolia Salisb.) with its high salicylate content is a promising source of herbal drugs. In the present study, seven dark-leaved willow clones were cultivated under short-rotation system with a two-year cultivation cycle. The yields of salicylates and biomass, and the concentrations of foliar phenolics were determined after the second cultivation cycle. Willow clones were treated by different cultivation methods, i.e. combinations of mulching (black polythene vs. cutter chip) and fertilisation (0, 25, 150 kg ha?1, N), with the objective of evaluating the most productive clone and cultivation method for herbal willow production. Furthermore, we compared our results to those obtained after the first cultivation cycle. Results showed that the yields of salicylates and biomass, and the concentrations of all foliar phenolic metabolites varied significantly amongst the clones. Biomass yields and salicylate yield were increased by polythene mulching, but the level of response varied between clones. Fertilisation (only the highest rate) caused an increase in yields, but the effect of fertilisation was smaller than that of mulching. Salicylate yield of most clones was higher than that had been during the previous rotation. Phenolic analyses showed that the concentrations of chlorogenic acid, total p-OH-cinnamic acids and soluble condensed tannins were higher in the willows grown in polythene mulch plots than in willows grown on cutter chip mulched plots. Furthermore, the concentrations of diglucoside of SaOH, salicin, disalicortin 1, disalicortin 2, chlorogenic acid, total chlorogenic acids and total flavonoids were higher in fertilized than in unfertilized willows. Salicortin, which was the most abundant salicylate, and total salicylates were not affected by fertilisation and mulching. The effects of fertilisation and mulching on several phenolics were clone-dependent. In conclusion, after two cultivation cycles, the cultivation methods were not effective in increasing the foliar total salicylate concentration, but rather increased the salicylate yield by enhancing the biomass of the synthesising tissues. Since biomass production was increased by the second cultivation cycle, the cultivation of herbal willows under a two-year cycle is recommended. The highly variable responses of the clones to treatments indicate that profitable willow cultivation for herbal industry is based on the right clone selection. 相似文献
99.
100.
J. Schittenhelm S. Westphal Susanne Toder E. Wagner 《Forstwissenschaftliches Centralblatt》1993,112(1):240-250
Die Auswirkungen verschiedener Stre?faktoren auf das antioxidative System wurden in sechsj?hrigen Klonfichten untersucht.
überflutung und Dunkelheit hatten nur geringen Einflu?. Im Gegensatz dazu wirkten sich die Stre?faktoren Trockenheit, K?lte,
Starklicht und sehr hohe Ozonkonzentrationen stark auf das antioxidative System aus. Die Effekte waren jedoch nicht einheitlich,
sondern waren je nach Stre?faktor unterschiedlich. Dies wird als ein Hinweis dafür gewertet, da? die Sch?den bei diesen Stre?faktoren
durch unterschiedliche toxische Sauerstoffspezies entstehen und da? sich die Sch?den unter Freilandbedingungen synergistisch
verst?rken k?nnen.
The effects of different stress factors on the antioxidative system of 6-year-old Norway spruces of the same clone were examined.
Flooding and permanent darkness had only minor effects. On the other hand drought, chilling, intense light, and very high
ozone concentrations showed strong but distinct consequences. This indicates that the damages by these stress factors are
due to different toxic oxygen species, and that the stress factors could produce synergistic damages under natural field conditions. 相似文献