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61.
62.
Julia Janke Martina Bandte Christian Ulrichs Giselher Grabenweger Barbara Jäckel Hartmut Balder Carmen Büttner 《Journal of pest science》2009,82(1):47-53
The parasitoid wasp Pnigalio agraules (Wlk.) is a key natural enemy of the horsechestnut leafminer Cameraria ohridella Deschka and Dimić (Lepidoptera: Gracillariidae). As a basis for mark-release-recapture studies, aimed at investigating the
dispersal of this parasitoid in the field, adults of P. agraules were marked using a vertebrate-specific immunoglobulin (IgG). The marker was later detected by double antibody sandwich enzyme-linked
immunosorbent assay (DAS-ELISA). The IgG was either applied externally by spraying or internally by feeding an IgG-enriched
diet. Different concentrations of the marker were used and the influence of abiotic (climatic conditions, time elapsed between
marking and marker examination) and biotic factors (sex and age of the parasitoids) on the detection of the immunomarker was
tested. External marking by spraying led to more homogeneous labelling than feeding the marker. Parasitoids labelled with
0.25 mg rabbit IgG per ten individuals contained enough immunomarker to be easily distinguished from unmarked ones. Neither
the climatic conditions nor the sex or age of the insects had an influence on the detection of the marker. The IgG remained
well detectable during the entire lifespan of the parasitoids, which was not negatively affected by the marking procedure.
Serological marking can be used to investigate the dispersal behaviour of beneficial insects within mark-release-recapture
studies. 相似文献
63.
In a small‐plot trial different doses of sewage sludge (equivalent 82‐330 tons of dry matter per hectare) were incorporated in 0—25 cm depth (1982—1985). The aim of the investigations was to study the fate of the heavy metals Zn, Cd, Cu, Ni, Pb, and Cr, to determine their concentration in different soil fractions using a sequential extraction method and to ascertain their uptake by Zea mays L. plants. Eleven years after the last application the metals supplied with the sludge had moved as far as 50 cm in depth. The concentrations of Zn, Cd, Cu, Ni, and Cr in the saturation extract of the sampled soil layers were closely correlated with the concentrations of dissolved organic carbon (DOC). This result suggests that the heavy metal displacement was partly connected with the DOC movement in the soil. Considerable amounts of Zn and Cd coming from sewage sludge were found in the mobile fractions of the soil. Cu, Ni, and Pb were located especially in organic particles, and Cr was obviously bound by Fe‐oxides. Nine years after the last application the binding species of heavy metals were still different compared with those in the untreated soil. The whole withdrawal of heavy metals by plants yielded <1 % of the applied amounts. In the case of Zn the uptake from the sludge amended soil decreased during the experimental period. No similar tendency was observed for the other elements. In any case their annual variations of uptake exceeded the effect of sludge application. 相似文献
64.
Kiamycin (1), a new angucyclinone derivative possessing an 1,12-epoxybenz[a]anthracene ring system, was isolated from the marine Streptomyces sp. strain M268 along with the known compounds 8-O-methyltetrangomycin (3) and 8-O-methylrabelomycin (4). Their structures were elucidated by detailed spectroscopic analysis and comparison with literature data. The new angucyclinone derivative showed inhibitory activities against the human cell lines HL-60 (leukemia), A549 (lung adenocarcinoma), and BEL-7402 (hepatoma) with inhibition rates of 68.2%, 55.9%, and 31.7%, respectively, at 100 μM. It appears to have potential as an anticancer agent with selective activity. 相似文献
65.
Anne Hoffmann Sabine Milde Christine Desel Anja Hümpel Hartmut Kaiser Enno Hammes Mirva Piippo Arto Soitamo Eva‐Mari Aro Jóska Gerendás Burkhard Sattelmacher Ulf‐Peter Hansen 《植物养料与土壤学杂志》2007,170(1):87-97
Ammonium (NH ) nutrition causes retardation of growth in many plant species. In Arabidopsis grown with NH as the sole N source, growth retardation occurs already at early stages before photosynthesis has come to its full power. In order to describe the peculiarities of these retarded plants, they were compared with nitrate (NO )‐grown plants of the same age of 15 d. Photosynthetic activity as measured by CO2 uptake per unit chlorophyll is half as high in NH ‐grown seedlings as in NO ‐grown ones. This finding is confirmed by the analysis of chlorophyll fluorescence. Chloroplasts of NO ‐grown, but not of NH ‐grown, seedlings show starch deposits after 5 h of illumination with 40 μmol m–2 s–1. Gene‐expression analysis based on cDNA microarray and on Northern blots provide a clue about the biochemical background. After the first 2 weeks of growth, it seems that NO ‐grown seedlings subsist mainly on normal photosynthesis, whereas NH ‐grown seedlings still use lipids from the seeds stored in oleosomes. Corresponding to this observation, the mRNAs for enzymes of β‐oxidation are more strongly expressed in NH ‐grown seedlings. Different carbohydrate sources for sucrose synthesis are indicated by different gene expression. Higher gene expression of fructose bisphosphate aldolase (cytosolic isoform) in NO ‐grown seedlings indicates the dependence on photosynthesis, whereas a higher gene expression of PEP carboxykinase in NH ‐grown seedlings points to a prominent role of β‐oxidation of storage lipids still present. 相似文献
66.
67.
Stomatal uptake of mineral particles from a sprayed suspension containing an organosilicone surfactant 总被引:1,自引:0,他引:1
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Hartmut Kaiser 《植物养料与土壤学杂志》2014,177(6):869-874
Suspensions of insoluble particles are available on the market for foliar fertilizers. The question whether uptake of particles into the leaf interior is possible is under debate. The present study examines stomatal uptake of mineral particles into leaves of Avena sativa after spraying an aqueous suspension of calcium carbonate particles. By choosing a plant species with large stomata, confirming wide open stomata at the time of spraying and using a “super spreading” organosilicone surfactant, conditions were optimized for stomatal uptake. Scanning electron microscopical (SEM) examination confirmed particles in the intercellular spaces mostly in the vicinity of stomata. The number and size of particles was larger if leaves were treated with wide open than with closed stomata. The chemical identity of the particles was examined with electron‐dispersive x‐ray spectrography (EDX), confirming the presence of calcium carbonate particles among other particles of unknown origin. In conclusion, this study provides evidence for surfactant‐assisted stomatal uptake of mineral particles from sprayed suspensions in species with large stomata under specific conditions favoring stomatal uptake. 相似文献
68.
Böttcher Gerd Brumsack Hans-J. Heinrichs Hartmut Pohlmann Markus 《Water, air, and soil pollution》1997,94(3-4):289-296
A core consisting of minerogenic peat and organic-rich mineral sediments was collected at an altitude of 4275 m in the Ovejuyo valley, 100 km NE of La Paz in Bolivia. Age dating with 210Pb showed that the core represents approximately three centuries of sediment accumulation. None of the peats are ombrotrophic. Despite this, the Cd/Al, Cu/Al, Zn/Al, and Pb/Al ratios are all significantly higher in the surface layers, particularly in the top 6 cm: natural, abiological geochemical processes, therefore, cannot account for these elevated heavy metal/Al ratios. There are two possible explanations for the metal enrichments, relative to Al, in the surface layers: bioaccumulation by living plants, and anthropogenic atmospheric metal deposition. While the living plant layer may be responsible for the Cd, Cu, and Zn enrichments, this is an unlikely explanation for the Pb profile. In contrast to the other metals, the concentration of Pb in the first sample (dating from 1985-1994) is less than that of the second sample (dating from 1970-1985). The Pb/Al profile is consistent with the well documented, rapid increase in atmospheric Pb emissions during the present century (which accelerated following the introduction of leaded gasoline), and the decline in Pb pollution during the past 20 years (as a result of the introduction of unleaded gasoline). Thus, the Ovejuyo Valley mire has provided one of the first records of atmospheric Pb pollution in South America. 相似文献
69.
European Journal of Forest Research - 相似文献
70.
W. Laatsch J. N. Köstler v. Pechmann und H. Ziegler 《Forstwissenschaftliches Centralblatt》1958,77(7-8):255-256
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