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排序方式: 共有212条查询结果,搜索用时 15 毫秒
41.
Sobhy Nader Maher Mahmmod Yasser S. Refaai Walid Awad Ashraf 《Tropical animal health and production》2020,52(2):815-821
Tropical Animal Health and Production - Identification of reservoirs and transmission routes of digital dermatitis (DD)-associated Treponema spp. is considered an effective means for controlling DD... 相似文献
42.
Beigh Yasir Afzal Ganai Abdul Majeed Rather Mohammad Ashraf Athar Hakim Hamdani Shabeer Ahmad 《Tropical animal health and production》2020,52(5):2469-2480
Tropical Animal Health and Production - Assessment of the ruminant livestock feed sources availability, existing feeding practices, and nutrient balances was embarked at different zones of Gurez... 相似文献
43.
Kobra Maghsoudi Yahya Emam Muhammad Ashraf Mohammad Javad Arvin 《Journal of plant nutrition》2013,36(17):2121-2132
Role of exogenously-applied silicon (Si) on antioxidant enzyme activities was investigated in wheat under drought stress using a completely randomized factorial design with four replications. Drought stress significantly enhanced activities of ascorbate peroxidase, peroxidase, superoxide dismutase and catalase, and elevated accumulation of osmotically active molecules, soluble sugars and proline. Si application further enhanced activities of enzymes involved in oxidative defense system and accumulation of osmotically active molecules in drought-stressed plants. Under drought stress conditions, water shortage decreased protein content in all cultivars; however, application of Si increased it. Pollen area ratio was lower than 1 for cvs. Shiraz and Marvdasht under drought, but greater than 1 for cvs. Chamran and Sirvan. Water-limited regimes resulted in decreased leaf Ψw in all cultivars, but Si supply was effective in improving Ψw under water-limited regimes. Water shortage increased leaf K, Mg, and Ca concentrations. Under drought stress, Si-treated plants had higher K concentration than the none-treated plants. 相似文献
44.
AZ‐Germ Salt II, a salt tolerant line of alfalfa (Medicago sativa L.) at the germination stage, was compared with its parent line Mesa Sirsa in sand culture at the germination and seedling stages and in hydroponic culture at the adult stage under greenhouse conditions. The sodium chloride (NaCl) treatments used were 0 or 100 mol/m3 in half strength Hoagland nutrient solution. AZ‐Germ Salt II was superior to Mesa Sirsa in biomass production at all three stages. AZ‐Germ Salt II had significantly greater chloride (Cl) in the plumules and radicle than Mesa Sirsa at the germination stage. The two lines did not differ in shoot and root sodium (Na) and shoot Cl at the seedling stage. However, at the adult stage AZ‐Germ Salt II accumulated significantly higher Na in the shoots and roots and Cl in the shoots compared with Mesa Sirsa. The two lines did not differ in tissue potassium/sodium (K/Na) ratios in all three experiments, although K concentrations were higher in the seedling shoots and roots, and in the plumules of AZ‐Germ Salt II than Mesa Sirsa. The K versus Na selectivities were higher in the plumules and seedling shoots and roots of AZ‐Germ Salt II compared with Mesa Sirsa, whereas at the adult stage the reverse was true. The lines also did not show any difference in tissue calcium (Ca) concentrations at any stage. It is concluded that salt tolerance in these two lines is not age‐dependent. The pattern of ion accumulation varies with the change in growth stage. Generally there is a positive correlation between Na and Cl accumulation and growth in alfalfa. 相似文献
45.
Hong Y Lin S Jiang Y Ashraf M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):200-204
Eriobotrya plants are known to have significant amounts of phenolics and flavonoids, and exhibit a strong antioxidant activity. Experiments
were conducted to examine variation in the contents of total phenolics and flavonoids, and antioxidant activities in the leaves
of 11 Eriobotrya species (Tibet loquat, Daduhe loquat, Hengchun loquat, Taiwan loquat, Oak leaf loquat, Bengal loquat, Fragrant loquat, Guangxi
loquat, Obovate loquat, Big flower loquat, and common loquat, the last species include two materials, one is a cultivar ‘Zaozhong
6’, another is a wild tree). In these species, ‘Zaozhong 6′ loquat is a cultivar. The leaf extracts of ‘Tibet’, ‘Obovate’,
‘Taiwan’, ‘Bengal’ and ‘Hengchun’ loquats exhibited significantly higher contents of total flavonoids and total phenolics,
compared with those of other species. Of these 11 species, the highest contents of total phenolics and total flavonoids were
observed in ‘Tibet’ and ‘Obovatae’ loquats, respectively. The significantly stronger antioxidant abilities assessed by the
DPPH radical scavenging activity and reducing power were obtained in the leaf extracts of ‘Taiwan’, ‘Tibet’, ‘Bengal’, ‘Oak
leaf’, ‘Hengchun’ and ‘Obovate’ loquats, compared with the other species. In addition, significant correlations were found
between the contents of total phenolics or flavonoids and DPPH radical scavenging activity/reducing power. This work indicates
that the leaf extracts of the wild Eriobotrya species, ‘Tibet’, ‘Obovatae’, ‘Taiwan’, ‘Bengal’, ‘Oak leaf’ and ‘Hengchun’ loquats, exhibited significantly higher levels
of total phenolics and flavonoids, and significantly stronger antioxidant activities, compared with the cultivated species,
‘Zaozhong 6′ loquat, which suggests that these wild species have a better utilization value. 相似文献
46.
Ashraf M El‐Sayed Lee‐Anne Manning C Rikard Unelius Kye Chung Park Lloyd D Stringer Nicola White Barry Bunn Andrew Twidle David M Suckling 《Pest management science》2009,65(9):975-981
BACKGROUND: The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. RESULTS: Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4‐hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non‐baited trap. Accordingly, a series of straight‐chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4–22.6 mg day?1 of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7–16.8 mg day?1 of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. CONCLUSION: These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. Copyright © 2009 Society of Chemical Industry 相似文献
47.
Sahar S. Taha Ashraf Sh. Osman 《The Journal of Horticultural Science and Biotechnology》2018,93(5):545-554
To study the effect of soil application of potassium humate (KH) (0, 70 and 140 Kg ha?1) on agronomic, biochemical attributes, and yield and its components on bean (Phaseolus vulgaris L.) cultivars ‘Bronco’ grown under two sites having different level of salinity (EC = 3.00 or 5.00 ± 0.20 dS m?1). Two field trials were conducted at the Agriculture Test Station, Faculty of Agriculture, Fayoum University, in 2014 and 2015. The obtained results indicated that addition of KH increased all of the studied growth parameters, i.e. plant height, number of leaves, leaf area, stem diameter and canopy dry weight. Moreover addition of KH significantly increased membrane permeability measurements. KH significantly increased chemical composition related to salt tolerant either inorganic e.g. N, P, K, and decreased Na and Cl contents of leaves or organic components e.g. chlorophyll a + b, carotenoids, anthocyanin total phenolics, total flavonoids and proline. DPPH radical-scavenging activity and yield and its components were increased. The soil application of KH was found to be highly effective at improving the growth and yield of bean plants by alleviating the inhibitory effects of soil salinity stress. 相似文献
48.
Esmaeili Saber Mohabati Mobarez Ashraf Khalili Mohammad Mostafavi Ehsan Moradnejad Pardis 《Tropical animal health and production》2019,51(6):1345-1355
Tropical Animal Health and Production - Q fever is a major zoonotic disease in the world. The aim of this meta-analysis was to estimate the prevalence of Coxiella burnetii in animal milk in Iran.... 相似文献
49.
Ashraf Sayed Awaad Mohamed Kamal Merai Abdel Maksoud Mohamed Zaki Fathy 《Anatomia, histologia, embryologia》2019,48(4):279-289
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep. 相似文献
50.
This study investigated whether the exogenous application of glycine betaine (GB) could alleviate the adverse effects of water deficit on sunflower. Two sunflower lines, Gulshan-98 and Suncross, were subjected to water deficit at the vegetative or the reproductive stages of plant growth. Three levels (0, 50 and 100 mmol l−1 ) of GB were applied as a pre-sowing seed treatment or as a foliar spray at the time of initiation of water deficit at the vegetative or reproductive stages. Foliar application of GB at the time of initiation of water deficit treatments showed a marginal increase in shoot biomass in drought-stressed plants. Exogenously supplied GB as a foliar spray also showed a positive role in reducing the effects of water deficit on net CO2 assimilation rate, transpiration rate and sub-stomatal CO2 concentration in both sunflower lines. Pre-sowing seed treatment with GB had no effects on the above-mentioned physiological and growth attributes in both normally irrigated and drought-stressed plants. Taken together, foliar application of GB increased net CO2 assimilation rate which in turn showed a slight increase in growth of water-stressed plants but this increase was not related to stomatal regulation. 相似文献