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781.
Alexia Stokes Franck Salin Adzo Dzifa Kokutse Stéphane Berthier Henri Jeannin Shaun Mochan Luuk Dorren Nomessi Kokutse Murad Abd.Ghani Thierry Fourcaud 《Plant and Soil》2005,278(1-2):107-117
In order to determine the mechanical resistance of several forest tree species to rockfall, an inventory of the type of damage
sustained in an active rockfall corridor was carried out in the French Alps. The diameter, spatial position and type of damage
incurred were measured in 423 trees. Only 5% of trees had sustained damage above a height of 1.3 m and in damaged trees, 66%
of broken or uprooted trees were conifers. Larger trees were more likely to be wounded or dead than smaller trees, although
the size of the wounds was relatively smaller in larger trees. The species with the least proportion of damage through stem
breakage, uprooting or wounding was European beech (Fagus sylvatica L.). Winching tests were carried out on two conifer species, Norway spruce (Picea abies L.) and Silver fir (Abies alba Mill.), as well as European beech, in order to verify the hypothesis that beech was highly resistant to rockfall and that
conifers were more susceptible to uprooting or stem breakage. Nineteen trees were winched downhill and the force necessary
to cause failure was measured. The energy (E
fail) required to break or uproot a tree was then calculated. Most Silver fir trees failed in the stem and Norway spruce usually
failed through uprooting. European beech was either uprooted or broke in the stem and was twice as resistant to failure as
Silver fir, and three times more resistant than Norway spruce. E
fail was strongly related to stem diameter in European beech only, and was significantly higher in this species compared to Norway
spruce. Results suggest that European beech would be a better species to plant with regards to protection against rockfall.
Nevertheless, all types of different abiotic stresses on any particular alpine site should be considered by the forest manager,
as planting only broadleaf species may compromise the protecting capacity of the forest e.g. in the case of snow avalanches. 相似文献
782.
On the consequences of aluminium stress in rye: repression of two mitochondrial malate dehydrogenase mRNAs 下载免费PDF全文
D. Abd El‐Moneim R. Contreras J. Silva‐Navas F. J. Gallego A. M. Figueiras C. Benito 《Plant biology (Stuttgart, Germany)》2015,17(1):123-133
Plants have developed several external and internal aluminium (Al) tolerance mechanisms. The external mechanism best characterised is the exudation of organic acids induced by Al. Rye (Secale cereale L.), one of the most Al‐tolerant cereal crops, secretes both citrate and malate from its roots in response to Al. However, the role of malate dehydrogenase (MDH) genes in Al‐induced stress has not been studied in rye. We have isolated the ScMDH1 and ScMDH2 genes, encoding two different mitochondrial MDH isozymes, in three Al‐tolerant rye cultivars (Ailés, Imperial and Petkus) and one sensitive inbred rye line (Riodeva). These genes, which have seven exons and six introns, were located on the 1R (ScMDH1) and 3RL (ScMDH2) chromosomes. Exon 1 of ScMDH1 and exon 7 of ScMDH2 were the most variable among the different ryes. The hypothetical proteins encoded by these genes were classified as putative mitochondrial MDH isoforms. The phylogenetic relationships obtained using both cDNA and protein sequences indicated that the ScMDH1 and ScMDH2 proteins are orthologous to mitochondrial MDH1 and MDH2 proteins of different Poaceae species. The expression studies of the ScMDH1 and ScMDH2 genes indicate that it is more intense in roots than in leaves. Moreover, the amount of their corresponding mRNAs in roots from plants treated and not treated with Al was higher in the tolerant cultivar Petkus than in the sensitive inbred line Riodeva. In addition, ScMDH1 and ScMDH2 mRNA levels decreased in response to Al stress (repressive behaviour) in the roots of both the tolerant Petkus and the sensitive line Riodeva. 相似文献
783.
Phytochemistry Reviews - There are approximately 260 known species in the genus Millettia, many of which are used in traditional medicine to treat human and other animal ailments in various parts... 相似文献
784.
Mady Emad Ibrahim Shafik D. Randhir Reena Abd El-Hakim Ahmed F. Randhir Timothy O. 《Molecular biology reports》2022,49(5):3863-3873
Molecular Biology Reports - Germplasm identification is an essential connection linking the conservation and exploitation of crop genetic resources in several plant breeding programs. This study... 相似文献
785.
Resinous beehive product propolis has many biological activities. It contains various aromatic substances that have great differences in their chemical composition depending on the natural flora. Thus, chemical characterization and biological properties of propolis samples is an important subject for the pharmaceutical industry. In this study, the propolis samples collected from three cities in Turkey were prepared as methanol (MEP), ethanol (EEP), chloroform (ChlEP), hexane (HxEP), and ethyl acetate (EAEP) extracts using an ultrasonic assisted technique. The antioxidant capacities of the samples were evaluated by free radical scavenging activity (DPPH), cation radical scavenging activity (ABTS), and reducing activity (CUPRAC) and (FRAP). The strongest biological activities were detected in ethanol and methanol extracts. Enzyme inhibition of the propolis samples were determined against the human glutathione S-transferase (GST) and angiotensin converting enzyme (ACE). IC50 values of MEP1, MEP2, and MEP3 samples against the ACE were found as 13.9 μg/mL, 14.8 μg/mL, and 12.8 μg/mL, while against the GST IC50 values of MEP1, MEP2, and MEP3 samples were as 5.92 μg/mL, 9.49 μg/mL, and 5.72 μg/mL. To know the possible causes of the biological test results advanced LC/MS/MS method was applied. trans-ferulic acid, kaempferol, and chrysin were found as the most abundant phenolic compounds in each sample. The propolis extracts obtained using the proper solvent have a good potential to be used in pharmaceuticals to treat the diseases related to oxidative damage, hypertension, and inflammation. Finally, the interactions between chrysin, trans-ferulic acid and kaempferol molecules with ACE and GST receptors were analyzed using molecular docking study. Selected molecules interact with active residues by binding to the active site of the receptors. 相似文献
786.
787.
Rofeal Marian El-Malek Fady Abd 《International journal of peptide research and therapeutics》2021,27(1):447-455
International Journal of Peptide Research and Therapeutics - Biosurfactants are natural compounds produced biologically by certain bacterial strains. They are promising alternatives in several... 相似文献
788.
Russian Journal of Plant Physiology - Vicia faba (L.) is a valuable grain legume, rich in nutrients and bioactive constituents with large genotypic variability in resistance to abiotic... 相似文献
789.
Fahd Mohammed Abd Al Galil Sureshchandra Popat Zambare Fahd A. Al-Mekhlafi Lamya Ahmed AL-Keridis 《Saudi Journal of Biological Sciences》2021,28(2):1267-1271
Forensic entomotoxicology has grown to impact judicial systems in developed countries. Where the use of insects and maggots as samples in death investigations as an alternative technique, especially following degradation or loss of the conventionally used samples. Carrion flies feed on dead bodies and may ingest toxic substances found in the dead body, especially when the body was poisoned before death. The knowledge of how the chemicals interact with the insect following ingestion is crucial to forensic entomotoxicologists. The study investigated the impact of dimethoate on the life cycle of four species of Calliphoridae flies, namely Chrysomya megacephala, Chrysomya saffranea, Chrysomya rufifacies and Chrysomya indiana. Various concentrations of dimethoate (1 ppm, 2 ppm, 3 ppm and 4 ppm) were utilized in the study. The rate of development of the carrion flies showed a negative correlation with the concentration of the chemical. This paper glares at the impact of the chemicals may pose to the insects, and how analysis of such impacts can guide forensic investigations of poisoning and help the investigators to solve the crime puzzle. 相似文献
790.
Mohamed A. Yassin Abdallah M. Elgorban Abd El-Rahim M.A. El-Samawaty Bandar M.A. Almunqedhi 《Saudi Journal of Biological Sciences》2021,28(4):2123-2127
The present study describes the biosynthesis of silver nanoparticles, using the fungus Penicillium verrucosum. The silver nanoparticles were synthesised by reacting silver nitrate (AgNO3) with the cell free filtrates of the fungal culture, and were then characterized by UV–visible spectroscopy, transmission electron microscopy, scanning electron microscopy, energy-dispersive, and X-ray diffraction analysis to further evaluate their successful biosynthesis, optical and morphological features (size and shape), and crystallinity. The bioactivity of the synthesized nanoparticles against two phytopathogenic fungi i.e: Fusarium chlamydosporum and Aspergillus flavus was evaluated using nanomaterial seeding media. These biogenic silver nanoparticles were polydisperse in nature, with a size of 10–12 nm. With regard to the antifungal activity, 150 ppm of the nanoparticles suppressed the growth of F. chlamydosporum and A. flavus by about 50%. To the best of our knowledge, this is the first report on the use of P. verrucosum to synthesise silver nanoparticles. The present study demonstrates a novel, simple, and eco-friendly process for the generation of biofunctionally useful biogenic nanoparticles. 相似文献