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排序方式: 共有193条查询结果,搜索用时 62 毫秒
91.
Alhan Sariyev Celaleddin Barutcular Mert Acar Akbar Hossain Ayman EL Sabagh 《Phyton》2020,89(3):519-528
Maize being sub-tropical crop is sensitive to water deficit during the
early growth stages; particularly clay-rich soil, due to the compaction of the soil.
It is well-documented that potential sub-surface drip irrigation (SDI) (Full irrigation; SDIFull (100% field capacity (FC)), Deficit irrigation; SDIDeficit (70% FC))
improves water use efficiency, which leads to increased crop productivity; since it
has a constraint that SDI excludes soil air around the root-zone during irrigation
events, which alter the root function and crop performance. Additionally, in clayrich soils, the root system of plants generally suffers the limitation of oxygen,
particularly the temporal hypoxia, and occasionally from root anoxia; while
SDI system accomplishes with the aerating stream of irrigation in the rhizosphere
could provide oxygen root environment. The oxygen can be introduced into the
irrigation stream of SDI through two ways: the venturi principle, or by using solutions of hydrogen peroxide through the air injection system. Therefore, the application of hydrogen peroxide (H2O2; HP) can mitigate the adverse effect of soil
compactness and also lead to improving the growth, yield and yield attributes
of maize in clay-rich soil. Considering the burning issue, a field study was conducted in consecutive two seasons of 2017 and 2018; where hybrid maize was
cultivated as a second crop, to evaluate the effect of liquid-injection of H2O2
(HP) into the irrigation stream of SDI on the performance of maize in a clay-rich
soil field of Adana, Turkey. When soil water content decreased in 50% of available water, irrigation was performed. The amount of water applied to reach the
soil water content to the field capacity is SDIFull (100% FC) and 70% FC of this
water is SDIDeficit (70% FC). In the irrigation program, hydrogen peroxide (HP)
was applied at intervals of 7 days on average according to available water with
and without HP: SDIFull (100% FC) + 0 ppm HP with full SDI irrigation;
SDIFull (100% FC) + 250 ppm HP with deficit SDI irrigation; SDIDeficit
(70% FC) + 0 ppm HP, SDIDeficit (70% FC) + 250 ppm HP and SDIDeficit
(70% FC) + 500 ppm HP. Deficit irrigation (SDIDeficit (70% FC)) program
was started from tasseling stage and continued up to the physiological maturity
stage with sub-soil drip irrigation. H2O2 was applied 3 times during the growing season. Two years’ results revealed that the liquid-injection of H2O2 into the irrigation stream of SDI improved the growth and yield-related attributes and grain
yield of maize. Based on the obtained results, during the extreme climatic condition in the year 2017, SDIFull (100% FC) + 250 ppm HP was more effective than
SDIFull (100% FC) + 0 ppm HP on all traits for relative to full irrigation. While,
during the favourable climatic condition in the 2018 season, SDIFull (100% FC)
+ 250 ppm HP was more effective than full irrigation with SDIFull (100% FC) +
0 ppm HP for the grain yield, grains, and SPAD value. Accordingly, the most
effective treatment was SDIFull (100% FC) + 250 ppm HP, as it gave the highest
growth and yield-related attributes and grain yield of maize followed by
SDIDeficit (70% FC) + 250 ppm HP. Therefore, SDIFull with 250 ppm H2O2
using as liquid-injection may be recommended to mitigate the adverse effect of
soil compactness particularly water-deficit stress in clay-rich soil for the sustainability of maize production. 相似文献
92.
Zahoor Ahmad Ejaz Ahmad Waraich Celaleddin Barutçular Akbar Hossain Murat Erman Fatih ÇIĞ Hany Gharib Ayman EL Sabagh 《Phyton》2020,89(3):529-539
The main objective of the research is to assess the role of foliar application of silicon (Si) for enhancing the survival ability of wheat under drought stress
through improving its morphology, physicochemical and antioxidants activities.
Treatments were five doses of Si at the rate of 2, 4, 6 and 8 mM and a control. After
completion of seeds germination, pots were divided into four distinct groups at various field capacity (FC) levels, such as 100% FC (well-irrigated condition), 75% FC
(slight water deficit), 50% FC (modest water deficit) and 25% FC (severe water deficit stress condition). Foliar application of Si at the rate of 2, 4, 6 and 8 mM and a
control were given after 30 days of sowing at the tillering stage of wheat. Findings
of the present investigation indicated that increasing the level of water deficit stress
reduced the morphological parameters (such as root and shoot fresh and dry-biomass weight) and physico-biochemical events ((such as chlorophyll contents by
estimating SPAD value), total free amino acid (TFAA), total soluble sugar (TSS),
total soluble protein (TSP), total proline (TP), CAT (catalase), POD (peroxidase),
SOD (superoxide dismutase) and APX (ascorbate peroxidase)) of wheat; while
foliar application of Si at 6 mM at tillering stage enhanced the drought tolerance
in wheat by increasing morphology and physiochemical characters under all levels
of drought stress. Similarly, antioxidants activities in wheat also enhanced by the
application of Si at 6 mM under normal as well as all drought stress levels. Therefore, it may be concluded that foliar application of Si at 6 mM at the tillering stage
of wheat is an important indication for increasing the drought tolerance by improving the morphology, physico-biochemical and antioxidants activities in plants under
deficit water (drought) conditions. 相似文献
93.
Ahmed EL Bedewi Randa Yousef Dalia Abdel Halim Rehab Hegazy William Willis Lisa M. Miller Medhat EL Mofty 《International journal of peptide research and therapeutics》2013,19(3):203-207
Psoriasis vulgaris and, Lichen planus are cutaneous inflammatory conditions that usually exhibit distinctive morphology. Ten psoriasis vulgaris and, ten Lichen planus patients (mean age, 45 ± 10.27 years) with confirmed histopathological diagnoses were analyzed. In the current study synchrotron infrared (IR) microspectroscopy was used to differentiate between these two conditions based on their lymphocytic proteins analyses. It was found that β-sheets protein structure, known to represent cell apoptosis, were expressed significantly in Lichen planus conditions than that of the psoriasis vulgaris when analyzed against the established normal control groups of five patients of comparable age and, genders (P = 0.001, 0.03 respectively). Also, the amide 1 protein type within the epidermis of Lichen planus were expressed in significant proportions as compared to psoriasis vulgaris (P < 0.001). On the contrary, the amide 1 protein structural types were found clustered in psoriasis vulgaris in different IR spectra than that in Lichen planus as observed in a number of patients during this study. These observations indicated that the concentration of amide 1 protein in psoriasis vulgaris varies to that of Lichen planus. In conclusion, both psoriasis vulgaris and, Lichen planus have different types of epidermal and, dermal protein structures and, this information can be of clinical diagnostic and therapeutic use for these cutaneous inflammatory conditions in near future. 相似文献
94.
Hugo Roume Emilie EL Muller Thekla Cordes Jenny Renaut Karsten Hiller Paul Wilmes 《The ISME journal》2013,7(1):110-121
Mixed microbial communities are complex, dynamic and heterogeneous. It is therefore essential that biomolecular fractions obtained for high-throughput omic analyses are representative of single samples to facilitate meaningful data integration, analysis and modeling. We have developed a new methodological framework for the reproducible isolation of high-quality genomic DNA, large and small RNA, proteins, and polar and non-polar metabolites from single unique mixed microbial community samples. The methodology is based around reproducible cryogenic sample preservation and cell lysis. Metabolites are extracted first using organic solvents, followed by the sequential isolation of nucleic acids and proteins using chromatographic spin columns. The methodology was validated by comparison to traditional dedicated and simultaneous biomolecular isolation methods. To prove the broad applicability of the methodology, we applied it to microbial consortia of biotechnological, environmental and biomedical research interest. The developed methodological framework lays the foundation for standardized molecular eco-systematic studies on a range of different microbial communities in the future. 相似文献
95.
Stéphanie De Simoni Dominique Linard Emmanuel Hermans Bernard Knoops Julie Goemaere 《Journal of neurochemistry》2013,125(3):473-485
Peroxiredoxin‐5 (PRDX5) is an antioxidant enzyme which differs from the other peroxiredoxins with regards to its enzymatic mechanism, its high affinity for organic peroxides and peroxynitrite and its wide subcellular distribution. In particular, the mitochondrial isoform of PRDX5 confers a remarkable cytoprotection toward oxidative stress to mammalian cells. Mitochondrial dysfunction and disruption of Ca2+ homeostasis are implicated in neurodegeneration. Growing evidence supports that endoplasmic reticulum (ER) could operate in tandem with mitochondria to regulate intracellular Ca2+ fluxes in neurodegenerative processes. Here, we overexpressed mitochondrial PRDX5 in SH‐SY5Y cells to dissect the role of this enzyme in 1‐methyl‐4‐phenylpyridinium (MPP)+‐induced cell death. Our data show that mitochondria‐dependent apoptosis triggered by MPP+, assessed by the measurement of caspase‐9 activation and mitochondrial DNA damage, is prevented by mitochondrial PRDX5 overexpression. Moreover, PRDX5 overexpression blocks the increase in intracellular Ca2+, Ca2+‐dependent activation of calpains and Bax cleavage. Finally, using Ca2+ channel inhibitors (Nimodipine, Dantrolene and 2‐APB), we show that Ca2+ release arises essentially from ER stores through 1,4,5‐inositol‐trisphosphate receptors (IP3R). Altogether, our results suggest that the MPP+ mitochondrial pathway of apoptosis is regulated by mitochondrial PRDX5 in a process that could involve redox modulation of Ca2+ transporters via a crosstalk between mitochondria and ER. 相似文献
96.
Gamal E. S. Abo El‐Ghar Abd El‐Ghany M. EL‐Sayed Anwar E. El‐Shiekh Hosny S. A. Radwan 《Archives Of Phytopathology And Plant Protection》2013,46(6):531-543
A small‐plot tests were conducted on cowpea, Vigna ungiculata (L.) Walp, to determine the effectiveness of 14 selected insecticides representing four insecticide classes (organophosphates, carbamates, pyrethroids, and insect growth regulators, IGRs), and four insecticide/IGR mixtures on cowpea insect pests and its effects on certain beneficial insects. By day 3 after treatement, the insecticides phenthoate, isoxathion, cyanophos, carbaryl, and cypermethrin used at sub‐recommended rates reduced the leafhopper, Empoasca spp., populations by >83% than those in the control. On that day, all insecticide treatments significantly reduced the cowpea aphid, Aphis craccivora, numbers below that of the control. The prothiofos, isoxathion, pirimicarb, and fenpropathrin treatments provided continuing control to both leafhoppers and aphids through day 21 after spraying. It seems that most insecticide treatments were not effective in whitefly, Bemisia tabaci, control. The best control of the whitefly immatures was obtained by day 3 after spraying in plots received thiodicarb (76%) and fenpropathrin (60%). All selected insecticides and rates used had very low residual effect against B. tabaci immatures. By day 3 posttreatment, the carbaryl (2.02 kg/ha) caused completely protection for cowpea pods frMw blue pea butterfly, Lampides boeticus, larvae. The IGRs, flufenoxuron and Dowco‐439, applied alone and those applied in mixtures with insecticides, carbaryl/teflubenzuron, chlorpyrifos/XRD‐473, and methomyl/ flufenoxuron, exhibited satisfactory control (>81%) to butterfly larvae on day 7 posttreatment. All treatments did not exhibit a considerable residual activity against L. boeticus larvae through 2–3 weeks followed spray. Most insecticides applied at the higher rates used significantly reduced the numbers of limabean pod borer, Etiella zinckenella, larvae found in cowpea pods collected on day 7 after application. The IGRs, flufenoxuron and Dowco‐439, applied alone, at 0.119 kg/ha, or in mixtures, methomyl/flufenoxuron (0.167 kg/ha) and chlorpyrifos/Dowco‐439 (0.911 kg/ha) caused >73% control of E. zinckenella larvae through day 21 posttreatment. The best control of cowpea weevil, Callosobru‐chus spp., adults (>83%), on day 3 after spraying, was obtained in treatments of cyanophos (1.19 kg/ha), prothiofos (1.43 kg/ha), flufenoxuron (0.119 kg/ha), and chlorpyrifos/Dowco‐439 (0.911 kg/ha). The IGR flufenoxuron applied alone or in mixture, methomyl/flufenoxuron (0.164 kg/ ha) exhibited satisfactory residual activity against Callosobruchus adults through day 21 posttreatment. Percentage seed damage by the larvae of cowpea weevils was significantly lower in most treatments than that of control. Populations of insect predators found in all treated plots were extremely reduced than those found in untreated plots. By day 21 after spraying, the IGRs flufenoxuron, XRD‐473, and Dowco‐439, applied at the low rate of 0.071 kg/ha, seemed to be less effect against insect predators than other insecticides used. 相似文献
97.
ELŻBIETA GABAŁA 《Invertebrate reproduction & development.》2013,57(1-2):19-28
Summary The present paper is the first to give a comprehensive and detailed characterization of Sertoli cells in the isopod, Saduria entomon, based on transmission electron microscopy. Two types of Sertoli cells, A and B, were distinguished which clearly differ in their location in the wall of the testicular tubule, and in their morphology, ultrastructure, and function. Their occurrence is closely connected with the characteristic arrangement of germ cells inside the tubule. Sertoli A cells occupy only the part of the tubule containing spermatogonia and primary spermatocytes and they are associated with these cells by means of numerous ramified processes running in many directions. They are irregular in shape, but their shape and the ultrastructure are stable during maturation of the germ cells. Sertoli B cells, which compose most of the testicular tubule wall, form a columnar epithelium. They send long processes into the lumen of the tubule by means of which they make contact with maturing spermatids. The cytoarchitecture of the processes is highly variable and reflects their role in spermiogenesis and the formation of sperm bundles. After spermiation, when the apical part of the Sertoli cells has become flattened, they phagocytoze the residual cytoplasmic masses of spermatids, which undergo degradation in heterophagic vacuoles. Simultaneously, numerous autophagic vesicles appear. 相似文献
98.
99.
Evapotranspiration rates increased with leaf area and fell withits decline at the time of flowering of cotton plants (Gossypiumbarbadense L.) and this relation was maintained while the rateof pan evaporation was steadily decreasing. A similar relationshipwas established for the hyacinth bean (Dolichos lablab L.) butevapotranspiration dropped at the onset of flowering, at thetime when leaf area was still increasing and the evaporatingpotential of the atmosphere began to rise. Evapotranspirationper unit area of leaf surface per day declined progressivelywith age for both species. 相似文献
100.