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151.
A Schrader O Schulz H V?lker H Puls 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(5-6):218-221
It is reported of botanical intoxications in 1379 ruminants (dairy cattle, beef cattle and ewes) in north-eastern Germany. The intoxications of these animals were caused by consumption of the following plants: meadow saffron (Colchicum autumnale L.), cowbane (Cicuta virosa L.), sweet clover (Melilotus alba MED.), sheep's sorrel (Rumex acetosella L.), bracken (Pteridium aquilinum KUHN) and St. John's wort (Hypericum perforatum L.). In all the five described cases animals died as a result of plant intoxications. The authors come to the conclusion that periodical inspections of the meadows are necessary, checking the plants in cooperation with veterinary surgeons. 相似文献
152.
Precambrian sponges with cellular structures 总被引:2,自引:0,他引:2
Sponge remains have been identified in the Early Vendian Doushantuo phosphate deposit in central Guizhou (South China), which has an age of approximately 580 million years ago. Their skeletons consist of siliceous, monaxonal spicules. All are referred to as the Porifera, class Demospongiae. Preserved soft tissues include the epidermis, porocytes, amoebocytes, sclerocytes, and spongocoel. Among thousands of metazoan embryos is a parenchymella-type of sponge larvae having a shoe-shaped morphology and dense peripheral flagella. The presence of possible amphiblastula larva suggests that the calcareous sponges may have an extended history in the Late Precambrian. The fauna indicates that animals lived 40 to 50 million years before the Cambrian Explosion. 相似文献
153.
Evaluation of Limnocorrals for Studying the Effects of Phytotoxic Compounds on Plankton and Water Chemistry in Aquaculture Ponds 总被引:1,自引:0,他引:1
Kevin K. Schrader Craig S. Tucker Marjan Q. de Regt Susan K. Kingsbury 《Journal of the World Aquaculture Society》2000,31(3):403-415
Abstract.— Two studies were conducted to evaluate the potential use of limnocorrals (in situ enclosures) for evaluating the effects of phytotoxic compounds on phytoplankton community structure and water quality. Limnocorrals consisted of open‐bottomed, fiberglass cylinders that were 2.44 m in diameter and 1.53 m high. The enclosures were placed in an aquaculture pond and allowed to settle 10–20 cm into the bottom mud, forming a watertight seal that isolated approximately 5.5 m3 of pond water. The first study evaluated the effect of water mixing on environmental conditions within limnocorrals. Mixing was accomplished by injecting air through airstones suspended inside the enclosures. Conditions in unmixed limnocorrals rapidly deviated from conditions in the pond and in aerated enclosures, with overall phytoplankton biomass decreasing while abundance of cyanobacteria and concentrations of soluble reactive phosphorus increased. Conditions in limnocorrals with continuous mixing also deviated from conditions in the pond. Environmental conditions among replicate mixed enclosures were, however, relatively consistent and stable for at least 2 wk. The second study evaluated the use of limnocorrals for testing the effects of phytotoxic compounds on phytoplankton community structure and water quality. A commercial chelated copper algicide was added to randomly selected, mixed limnocorrals at the label‐recommended rate. The algicide killed nearly all phytoplankton in the treated enclosures within 1 wk; however, treated limnocorrals were rapidly recolonized by green algae and diatoms. Conditions in untreated limnocorrals remained relatively stable and consistent among replicates for 16 d, after which total phytoplankton biomass began to decrease, possibly due to nutrient depletion within the enclosures. Although conditions inside the enclosures deviated with time from those in the surrounding pond water, mixed limnocorrals appear to provide a convenient and reliable method for short‐term studies of algicides and other water quality manipulations. 相似文献
154.
Pox virus isolated from psittacine birds was used as a vaccine in trials with love birds (Agapornis roseicollis). The vaccine was applied by wing-web puncture using single- and double-needle applicators. Immunity was effective against challenge with virulent psittacine pox virus administered via the feather follicle/thigh. When unvaccinated contact control birds were placed with the vaccinated individuals immediately post-vaccination, virus spread was evident. However, susceptible birds placed with vaccinated ones at 27 days postvaccination remained uninfected for 11 weeks. The importance of a high vaccine virus titer was observed. 相似文献
155.
Global trade of plants and plant products facilitates the international movement of pests. The introduction of new pests in an area may have huge economic consequences for local plant production, and should be avoided. The European Union (EU) imports large quantities of fresh fruit from all over the world, which could be a pathway for exotic pests. This review aimed to identify pests not yet present or regulated in the EU that may enter the territory with the fruit trade and damage fruit production in Europe. Pests of Vaccinium (blueberry), apple, grape, orange and mandarin were screened to assess the likelihood of their being associated with these fruit, their impact, their geographical distribution, whether they are intercepted in trade and whether they are spreading or emerging. They were further ranked to produce alert lists of 30 to 36 pests for each fruit species. These lists are presented as well as other findings on contaminants and newly introduced pests. Datasheets on those pests were prepared and are available as supporting information to this article as well as in the EPPO Global Database ( https://gd.eppo.int/ ). This work within the EU project DROPSA aimed to raise the awareness of importers and regulatory authorities to the potential risk of introducing pests with the fruit trade. 相似文献
156.
Oliver Fried Ingolf Kühn Julian Schrader Van Sinh Nguyen Erwin Bergmeier 《Paddy and Water Environment》2018,16(2):359-378
Which plant species can be found on rice field bunds and what are the prevailing life forms? Which plant communities occur and what are the main environmental drivers and phytogeographic patterns shaping these communities? How do species diversity and composition differ between bunds and paddies? To answer these questions, 133 vegetation relevés using the Braun-Blanquet method were collected in lowlands and uplands of Vietnam and the Philippines between 2012 and 2015. Soil samples were collected and farmers were interviewed. Properties of soil, climate, and geography were assessed, further structural parameters, landscape heterogeneity, seasonality, management and intensity of cultivation. Hierarchical UPGMA cluster analysis and NMDS ordinations were performed to visualize variation in plant community composition and the determinants. We found 302 vascular plant species, of which 94 species are red listed by the IUCN (under category “Least concern”). Therophytes and helophytes are the prevailing life forms. Six clusters of plant communities were classified, and temperature, soil acidity, land use intensity and nutrient availability were identified (according to relevance) as explanatory variables. Bunds revealed higher species richness than paddies and bunds in mountain areas were more species-rich than those in the lowlands. We conclude that the composition of bund communities provides valuable information on environmental and biogeographical conditions of the local rice landscapes, and that it is probably the best applicable and most reliable indicator of management intensity. 相似文献
157.
158.
Mirata MA Wüst M Mosandl A Schrader J 《Journal of agricultural and food chemistry》2008,56(9):3287-3296
The biotransformation of (+/-)-linalool was investigated by screening 19 fungi. Product accumulation was enhanced by substrate feeding and, for the first time, lilac aldehydes and lilac alcohols were identified as fungal biotransformation byproduct using SPME-GC-MS headspace analysis. Aspergillus niger DSM 821, Botrytis cinerea 5901/02, and B. cinerea 02/FBII/2.1 produced different isomers of lilac aldehyde and lilac alcohol from linalool via 8-hydroxylinalool as postulated intermediate. Linalool oxides and 8-hydroxylinalool were the major products of fungal (+/-)-linalool biotransformations. Furanoid trans-(2 R,5 R)- and cis-(2 S,5 R)-linalool oxide as well as pyranoid trans-(2 R,5 S)- and cis-(2 S, 5 S)-linalool oxide were identified as the main stereoisomers with (3 S,6 S)-6,7-epoxylinalool and (3 R,6 S)-6,7-epoxylinalool as postulated key intermediates of fungal (+/-)-linalool oxyfunctionalization, respectively. With a conversion yield close to 100% and a productivity of 120 mg/L.day linalool oxides, Corynespora cassiicola DSM 62485 was identified as a novel highly stereoselective linalool transforming biocatalyst showing the highest productivity reported so far. 相似文献
159.
白僵菌是昆虫的重要病原真菌之一,用于防治多种农林害虫,但环境湿度是影响防治效果的重要因素.因此研究白僵菌的新剂型,提高白僵菌孢子萌发率具有重要意义.本论文在室内设立不同相对湿度,比较白僵菌分生孢子及其微胶囊剂活性.结果表明,随着相对湿度的增加孢子萌发率也增大.水悬液分生孢子萌发率最高达55%,最低为8%;氯化钙悬液孢子萌发率不足10%;微胶囊剂孢子萌发率可高达91%,最低为33%.室内模拟野外条件测定相同分生孢子浓度下的白僵菌水悬液和及其微胶囊剂对沙棘木蠢蛾幼虫的侵染,沙棘木蠢蛾幼虫的死亡率分别为45.54%和84.54%,说明白僵菌微胶囊剂对沙棘木蠢蛾幼虫的侵染明显高于其分生孢子水悬液. 相似文献
160.
[Objective] The experiment explored of resistance of different Medicago sativa through synthetic variations of all physiological indexes and the correlation analysis between physiological activity and damage degree after thrips damage. [Method] According to studying physiological activity (POD activity, SOD activity, PPO activity, PAL activity, MDA content and free proline content) of alfalfa in alfalfa resistance to different number of thrips, the correlation between physiological activity and resistance was investigated. [Result] It was shown that there were negative correlations among POD, SOD, PPO, PAL, MDA, free praline and the number of thrips, and there were negative correlations among POD, SOD, PPO, PAL, MDA, free praline and CAT. The content changes of POD,SOD,PPO,CAT,MDA and free proline in high resistant alfalfa were slow and PAL was quick and the activities of PPO,PAL,CAT were high, and the activities of POD、SOD were low. [Conclusion] The research provided theoretical basis and materials for identifying resistance varieties of alfalfa to thrip. 相似文献