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251.
Khalil Mohamed Salah Abd El-Aziz Mahmoud Hamdy Selim Rasha El-Sayed 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):799-812
European Journal of Plant Pathology - Root-knot nematodes (Meloidogyne spp.) have been reported to be responsible for large economic losses of agricultural crops due to their wide host range and... 相似文献
252.
Elshahawy Ibrahim E. Abd El-Wahed Mohamed S. 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(3):673-693
European Journal of Plant Pathology - Late wilt, a vascular disease caused by the fungus of Cephalosporium maydis, is considered one of Egypt’s most severe maize threats. The purpose of this... 相似文献
253.
The use of peatlands in the humid tropics requires drainage to remove excess rainfall. The design principles for the drainage systems currently being implemented on peatlands are the same as for mineral soils. The objective of such systems is the timely removal of excess rainfall by surface runoff. For peatlands, with their different soil-hydraulic characteristics, these systems have resulted in poor watertable control and high rates of irreversible subsidence. Concerns about this rate of subsidence and the level of sustainability of the present land use have prompted a study to develop a new water management system. This new system includes a shift from a drainage system that focuses on discharge of excess water towards a system that combines drainage and water conservation. In the new two-step design, the drain spacing and corresponding drain discharges are obtained with a steady-state approach. These outputs are used to calculate the capacity of the drains, including control structures, using an unsteady-state approach. The new system results in a shallower but more narrowly spaced drainage system and maintains a more constant but relatively high watertable and reduces subsidence. It should be remembered however, that even with the improved water management, subsidence cannot be arrested; it is the price one has to pay for the use of tropical peatlands. 相似文献
254.
Callus and differentiated shoots initiated from Solanum tuberosum L. on MS media containing BA, IAA, and Kin. Glycoalkaloids are produced in callus and shoots in concentrations higher than original tubers using HPLC. Callus methanolic extract had promising anticancer activity with low IC50 values against human carcinoma cell lines of breast, lymphoplastic leukemia, larynx, liver, cervix, colon, and brain, IC50 (µg/mL) were 2.7, 3.7, 6, 6.7, 10, 13.6, and 22.3 respectively. Antioxidant capacity of the extract (76.4%) performed using ESR. Preliminary screening showed that the extract exhibited in vitro virucidal activity against Herpes simplex. The extract possessed in vitro schistomicidal and fasciolicidal activity. 相似文献
255.
Prof. Dr. Nadia Z. Dimetry A. A. Barakat E. F. Abdalla H. E. El-Metwally A. M. E. Abd El-Salam 《Journal of pest science》1995,68(2):39-41
Laboratory evaluation of Neem Azal-S and Margosan-O was carried out against the adult and larvae ofLiriomyza trifolii Burgess. The feeding deterrent activity of both compounds was significantly realized against the adults particularly at high concentrations which lasted for 5 days after treatment. Both formulations also deterred the females from laying eggs and the percentage of oviposition deterrent index (ODI) reached 80.7 and 52.6 for Neem Azal-S and Margosan-O (2%), respectively.Post infestation treatment of bean seedlings containing 3rd instar larvae indicated that the toxic action of the tested extracts was quite limited. However, different percentages of malformed pupae were obtained. The sex ratio between the resulting adults was nearly unaffected with the exception of individuals whose larvae were treated with 2% Neem Azal-S where all the resulting progenies were females.With 2 tables 相似文献
256.
Mohamed Shaban Mostafa R. AbuKhadra Fadya M. Nasief H. M. Abd El-Salam 《Water, air, and soil pollution》2017,228(11):450
Natural zeolite clinoptilolite and synthetic zeolite Na-A were characterized using XRD and SEM to be used as adsorbents for ammonia from aqueous solutions, ground water, and sewage water. Clinoptilolite was mechanically activated for 2, 4, 6, and 8 h to study the effect of activation in enhancing the adsorption capacity. The adsorption by activated natural zeolite and synthetic zeolite is high pH dependent and achieve the best values at pH?=?7. The adsorption capacity of activated natural zeolite increases with increasing the activation from 2 to 8 h achieving removal percentage close to that obtained using synthetic zeolite. The equilibrium was obtained after 60 min for synthetic zeolite and all the activated natural zeolite (except 2-h-activated product, the equilibrium was achieved after 30 min). The kinetic studies reflected the high fitness of the adsorption results of activated natural zeolite products and synthetic zeolite with pseudo-second-order model rather than the other kinetic models. The obtained isotherms reflected the formation of S-type isotherm curve for the adsorption using mechanically activated clinoptilolite and L-type curve for the uptake using synthetic zeolite. The results represented well with Langmuir model followed by Temkin and Freundlich model for adsorption using synthetic zeolite. The uptake using mechanically activated clinoptilolite can be represented by Temkin model rather than both Langmuir and Freundlich models. Thermodynamic parameters indicate spontaneous endothermic adsorption of ammonia using all the zeolitic products under investigation. Finally, the mechanically activated natural zeolite and synthetic zeolite exhibit high efficiency in the removal of ammonia and other water pollutants from ground water and sewage water. 相似文献
257.
Sardar Khan Abd El-Latif Hesham Gu Qing Liu Shuang Jizheng He 《Journal of Soils and Sediments》2009,9(5):482-491
Background, aim, and scope
In the soil environment, polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are of great environmental and human health concerns due to their widespread occurrence, persistence, and carcinogenic properties. Bioremediation of contaminated soil is a cost-effective, environmentally friendly, and publicly acceptable approach to address the removal of environmental contaminants. However, bioremediation of contaminants depends on plant–microbe interactions in the rhizosphere. The microorganisms that can mineralize various PAHs have PAH dioxygenase genes like nahAc, phnAc, and pdo1. To understand the fate of pyrene in rhizospheric and non-rhizospheric soils in the presence or absence of Pb, pyrene biodegradation, bacterial community structure, and dioxygenase genes were investigated in a pot experiment. 相似文献258.
Functions of sodium (Na+) and potassium (K+) are closely associated. In some crops, Na+ is able to prevent or reduce considerably the occurrence of K+ deficiency. Sugar beet (Beta vulgaris L.) is a natrophilic crop, and positive effects of Na+ applications on yield were observed when K+ was sufficiently supplied. However, it is not known which specific function of K+ can limit the growth of sugar beet when K+ is substituted by an equivalent amount of Na+. Therefore, K+ substitution by Na+ was investigated for sugar beet in hydroponics. Surprisingly, no K+‐deficiency symptoms were observed. However, calcium (Ca2+) concentrations in the leaves were significantly decreased. Moreover, Ca2+ uptake and translocation through xylem sap were reduced in Na+‐treated plants. It is concluded that Ca2+ uptake by roots and its translocation via xylem sap primarily limit the possibility of K+ substitution by Na+ in sugar beet nutrition. 相似文献
259.
Osama Abd El-Salam Shalaby 《Journal of plant nutrition》2018,41(12):1597-1603
Environmental stresses, such as salinity, are becoming critical constraints to plant production especially in arid and semi-arid regions, one of the main targets of agricultural studies is to combat the environmental stresses on plants. An open field experiment was carried out to study the influence of sulfur (S) and urea on red cabbage plants under salt stress. The experiment was arranged as a split-plot design with three replications, the main plots included sulfur levels (0, 350, and 700 kg ha?1), while subplots included urea levels (0, 1, 2, and 4 g L?1). Results showed that urea spraying and sulfur soil additions resulted in improvement of growth and yield, and raised the level of potassium and nitrogen while lowering sodium content in plant leaves under salt stress conditions. Generally, larger and heavier heads were found with the application of 700 kg ha?1 sulfur and 2 g L?1 urea. 相似文献
260.
Hanafey F. Maswada Usama A. Abd El-Razek Abdel-Nasser A. El-Sheshtawy Abdelnaser A. Elzaawely 《Archives of Agronomy and Soil Science》2018,64(7):994-1010
Two field experiments were executed to investigate the effects of foliar-applied moringa (Moringa oleifera) leaf extract (MLE; 1:30 w/v) and salicylic acid (SA; 0.5 mmol), singly or in combination, on growth, physio-biochemical, yield attributes and water use efficiency (WUE) of maize (Zea mays L., Three Ways Cross 329) under full and deficit irrigation conditions. Deficit irrigation was carried out by withholding water for 36 d from 12 to 48 days after sowing (DAS). At vegetative stage, deficit irrigation signi?cantly decreased all growth criteria, chlorophyll a concentration, and relative water content (RWC). In contrast, deficit irrigation considerably increased the concentrations of carotenoids, proline, membrane permeability (MP) and malondialdehyde (MDA). Similarly, grain yield, most yield components and WUE were significantly depressed in drought-stressed plants. However, foliar-applied treatments particularly MLE+SA signi?cantly increased growth traits, photosynthetic pigments, RWC and proline accumulation associated with a simultaneous decrease in MP and MDA concentration under full and deficit irrigation conditions. The application of MLE+SA markedly increased grain yield, yield components and WUE over control (spray tap water). Overall, the combined application of MLE and SA could be used for alleviating the adverse effects of growth, physiology, yield criteria and WUE in drought-stressed maize plants. 相似文献