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211.
ter Halle A Wiszniowski J Hitmi A Ledoigt G Bonnemoy F Bonnet JL Bohatier J Richard C 《Pest management science》2009,65(1):14-18
BACKGROUND: Sulcotrione is a selective herbicide marketed for use in maize since 1993, but its environmental fate is not yet fully elucidated. A major metabolite resulting from cleavage between the two ring moieties, leading to 2‐chloro‐4‐mesylbenzoic acid (CMBA), has been identified; it presents a rather low toxicity. In photochemical studies this compound has also been claimed to be formed in high proportions. The present authors recently found that, under irradiation, sulcotrione mainly yields a cyclization product (CP). Thus, Sulcotrione photochemistry is still a matter of debate. The aim of the present work was to give an unequivocal answer to this issue. The potential toxicity of CP, CMBA and sulcotrione towards three organisms considered as representative of aquatic ecosystems was also evaluated. RESULTS: The main transformation product of sulcotrione is the cyclization product (CP), and CMBA is formed in smaller amounts. For the toxicological approach, the tested organisms were a bacterium, Vibrio fischeri (Bejerinck) Lehmann & Neumann, an alga, Pseudokirchneriella subcapitata (Korshikov) Hindak, and a protozoan, Tetrahymena pyriformis (Ehrenberg) Lwoff. Sulcotrione is more harmful towards the alga, but CP is more toxic to the bacterium and the protozoan. It must be noted that the measured toxicities are nonetheless rather low. CONCLUSION: On irradiation, sulcotrione mainly gives the photocyclization product, which presents a higher toxicity than sulcotrione and CMBA. This cyclization product should thus be considered in sulcotrione environmental risk assessment. Copyright © 2008 Society of Chemical Industry 相似文献
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Biochar‐compost substrates in short‐rotation coppice: Effects on soil and trees in a three‐year field experiment 下载免费PDF全文
Felix von Glisczynski Ralf Pude Wulf Amelung Alexandra Sandhage‐Hofmann 《植物养料与土壤学杂志》2016,179(4):574-583
Both biochar and compost may improve carbon sequestration and soil fertility; hence, it has been recommended to use a mixture of both for sustainable land management. Here, we evaluated the effects of biochar–compost substrates on soil properties and plant growth in short rotation coppice plantations (SRC). For this purpose, we planted the tree species poplar, willow, and alder in a no‐till field experiment, each of them amended in triplicate with 0 (= control) or 30 Mg ha?1 compost or biochar–compost substrates containing 15% vol. (TPS15) and 30% vol. biochar (TPS30). For three years running, we analyzed plant growth as well as soil pH, potential cation exchange capacity (CEC), stocks of soil organic carbon (SOC), total N, and plant‐available phosphate and potassium oxide.Biochar‐compost substrates affected most soil properties only in the topsoil and for a limited period of time. The CEC and total stocks of SOC were consistently elevated relative to the control. After three years the C gain of up to 6.4 Mg SOC ha?1 in the TPS30 plots was lower than the added C amount. Especially in the case of TPS30 treatment, C input was characterized by the greatest losses after application, although the black carbon of the biochar was not degraded in soil. Additionally, tree growth and woody biomass yield did not respond at all to the treatments. Overall, there were few if any indications that biochar–compost substrates improve the performance of SRC under temperate soil and climate conditions. Therefore, the use of biochar for such systems is not recommended. 相似文献
216.
The Eurasian badger (Meles meles) is a significant source of bovine tuberculosis in cattle in the UK and Ireland. Protection from infectious diseases, arising from maternal antibody transfer, is a well-established immunological phenomenon in mammals. In a previous study of wild badgers, transient serological responses in cubs were taken as evidence of maternal antibody transfer, and it was speculated this conferred protection from subsequent mycobacterial excretion following acquisition of tuberculosis. However successful defence against mycobacterial infections is likely to be dominated by a cell-mediated response. Using a substantially larger dataset from the same badger population, we revisited the hypothesis of maternally derived protection. Whilst we found a significant association between transient serological responses and absence of subsequent Mycobacterium bovis excretion, the likelihood of detection of such responses was not significantly associated either with badger age, or with infection in the breeding females within a cub's natal group. We concluded that although maternal antibody transfer in badgers almost certainly occurs, transient serological responses represent an invalid proxy, and the reduced likelihood of M. bovis excretion associated with transient responses was more likely to be due to the lower sensitivity of the Brock ELISA test in detecting badgers with less advanced disease. 相似文献
217.
Alexandra Rodríguez Jorge Durán José María Fernández-Palacios Antonio Gallardo 《Annals of Forest Science》2009,66(2):210-210
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Alexandra Yu. Novoselskaya-Dragovich Andrew V. Fisenko Fedor A. Konovalov Olga P. Mitrofanova Alexandra A. Shishkina Alexander M. Kudryavtsev 《Genetic Resources and Crop Evolution》2018,65(1):187-198
The origin, diversity and distribution of hexaploid wheat still remain somewhat unclear. In this study we examined the patterns of genetic diversity and phylogenetic relationships of seven hexaploid wheat species using integration site polymorphism of the LTR retrotransposons. Forty-eight accessions (most of them aboriginal) of seven wheat species from different geographical regions were studied using sequence-specific amplification polymorphisms. Phylogenetic relationships among species were constructed with SplitsTree 4.10 based on Dice’s matrices. Genetic distances between the accessions clustered with PAST software were estimated by principal component analysis. All the accessions differentiated into two main groups, one including European spelt and the other combining common, club and Indian dwarf (shot) wheat with the Asian spelt. The spelt species T. macha, T. vavilovii and spelt spike (speltoid) free-threshing T. petropavlovskyi were intermediate between the two groups. The separation of these spelt species from all other accessions was determined by differences in the A genome. European spelt was subdivided into Central European and Spanish branches. As different genetic pools were characteristic of European and Asian spelt, European spelt could not originate directly from the Asian one. Supposedly, the A genome mostly harbors the species-forming or taxonomically important genes that distinguish spelt species from free-threshing ones, which group together with Asian spelt. Grouping of Asian spelt with free-threshing wheat suggests their close relatedness and confirms the hypothesis that free-threshing hexaploid wheats originated from the Asian spelt ancestor. 相似文献
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Tatiana E. Samatadze Svyatoslav A. Zoshchuk Anna S. Khomik Alexandra V. Amosova Natalya Yu. Svistunova Svetlana N. Suslina Firdaus M. Hazieva Olga Yu. Yurkevich Olga V. Muravenko 《Genetic Resources and Crop Evolution》2018,65(6):1637-1647
Potentilla alba L. is a valuable medicinal plant widely used in folk and traditional medicine and particularly promising in complex treatment of thyroid pathology. Natural resources of this species are insufficient due to ever-growing use in contemporary medicine. Comprehensive investigations of different P. alba populations are essential for the successful extension of P. alba plantings. Aiming for a better understanding of karyotype structure, chromosome behaviour in meiosis and developing new diagnostic characters, we performed molecular cytogenetic characterization and leaf structure and ultrastructure analyses of two introduced P. alba samples originating from different habitats. Based on chromosome morphology, distribution of 45S/5S rDNA and DAPI-banding patterns, all chromosomes in the karyotypes were identified and the P. alba chromosomal idiogram was constructed. Our findings confirmed P. alba karyotype stability and also revealed several diagnostic characters of this species: the features of cells of upper and lower leaf epidermis, the presence of calcium oxalate druses and three types of leaf indumentum, essential for evaluation of genetic diversity in different populations, validation of raw materials and further selection progress. The meiotic abnormalities were detected probably related to low pollen activity and indicated the advantages of vegetative propagation in the development of a P. alba plantation system. 相似文献