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Effect of Electrolysis Technology on Saline Water under Utilize Nano-coated Electrodes
2021
Mohamed Hassan | Arafa Yasser | Khaled elbagoury
In this work, electromagnetic field technol-ogy and electrolysis technology with alumi-num electrodes coated with titanate nano-coat-ing were combined in different investigated parameters: power types (Electrolysis pass (EP) and Electromagnetic pass (EMP)), volt-age (12v, 24v and 36v) and nano-coating pa-rameters (coated and uncoated). The designed water treatment unit was evaluated by record-ing the EC-meter readings for 60min (each 5min) at a flow rate of 5l/min. Results show that the best salt rejection rate was 3.4% when EMP was used before EP where four elec-trodes were coated. In contrast, the other pa-rameters (EP, EMP+EP and EMP+EP (2 coated electrodes and 2 uncoated)) recorded the salt rejection rates 1.13%, 1.57% and 2.4%, respectively. This study is promising and opens the way for integrating both electrolysis and electromagnetic field technologies with on-farm irrigation systems and enhancing their efficiency using nanotechnology.
Afficher plus [+] Moins [-]Nitrogen Nutrition and Adaptation of Halophyte Chenopodium quinoa to Salt Stress
2021
Karema Tarek | Ibrahim Alshamy | Sayed Hussin | Sayed Eisa
There is little evidence that the nitrogen nu-trition supply at rates above or less than what is considered optimal in non-saline conditions improves growth and yield of halophyte crop cultivated under salt stress. Therefore, hypoth-esize of the present work was to find out the magnitude to which N could restore the harm-ful effects of salt stress on quinoa plants. A pot experiment was performed in greenhouse con-ditions to evaluate quinoa's response grown under water salinity treatments (0.0 & 200 mM NaCl) when nitrogen nutrition rates were limiting (50ppm), adequate (250 ppm), and ex-cess (450 ppm) to guide proper application rate of nitrogen fertilizer under salinity stress. The results indicated that, salinity caused a signifi-cant decrease in the vegetative growth of the plant. Consequently, all vegetative measure-ments were negatively affected. As a result, the seed yield decreased to more than 50%. The application of a moderate level of nitrogen (250 ppm) caused a significant ameliorative effect on seed yield by 126% under non saline conditions and 34.5 % under saline conditions compared to the low nitrogen level. The results did not improve any further with the applica-tion of a higher level of nitrogen. These results indicate that applying (N) in adequate may im-prove most traits and prove to be a physiolog-ical treatment to increase resistance against the negative effects of salt stress in quinoa.
Afficher plus [+] Moins [-]Potentiality of Using Mycorrhizae and Pseudomonas fluorescens in Reducing the Effect of Water Shortage on Broccoli Plants
2021
Dalia Abd El-Fattah | Fadl Hashem | Ahmed Farag
Accelerating global warming and water scarcity and improving water use efficiency are considered essential factors for achieving adequate crop development and productivity. Therefore, the authors targeted the use of arbuscular mycorrhizal fungi (AMF) and Pseudomonas fluorescens (Ps1) for improving growth, productivity, and water use efficiency of broccoli plants (Brassica olercea L. var. italica, cv. Belstar F1) under various irrigation regimes i.e., 50, 75, and 100% of crop evapotranspiration (ETc). Two greenhouse experiments were carried out in clayey soil. The combined inoculation of endomycorrhizae and Ps. fluorescens (Ps1) improved water use efficiency and consequently vegetative growth and yield. Under the applied irrigation regime 75% ETc of broccoli inoculated with both endomycorrhizae and Ps. fluorescens (Ps1) showed higher head weight (616 and 647 gram) than those grown under the irrigation regime 75% ETc combined with endomycorrhizae (568 and 559 gram) during the two seasons, respectively. However, a minimum yield value of 149 and 142 grams per plant was recorded for un-inoculated plants grown under 50% irrigation regime during both seasons. In conclusion, the combined inoculation with endomycorrhizae and Ps. fluorescens (Ps1) under irrigation regime 75% ETc was the optimum combination for increasing water stress resistance and broccoli productivity under water scar-city circumstances.
Afficher plus [+] Moins [-]Greenhouse and Laboratory Evaluation of The Efficiency of Green Silicon Dioxide Nanoparticles Against Tetranychus urticae (Koch)
2021
Heba Emam | Manal Ibrahim | Mervat Ibrahim | Salwa El-Sayed
Nanotechnology takes a significant position in controlling pests. Silicon dioxide nanoparticles (SiO2-NPs) is considered one of the best alter-natives to chemical pesticides for plant crop protection from harmful arthro-pods such as phytophagous mites, Tetranychus urticae. Therefore, this study aims to evaluate the effect of (SiO2-NPs) to control T. urticae. Under green-house conditions, the results revealed, in the larval stage, a high mortality percentage (99.05±0.83%) followed by eggs (98.74±1.22%). Besides, the nymph stage recorded high mortality (94.66±1.81%) at a high concentration of 1500 ppm. While the adult females of T. urticae recorded mortality of 91.92±1.02% after 72h. Eventually, the immature stages of T. urticae were susceptible to (SiO2-NPs). Meanwhile, at laboratory evaluation on immature stages of T. urticae which resulted from live treated females during 96h showed a sharp decrease in average numbers of eggs through 96h, at 1000 and 1500 ppm. No numbers of the larval stage were recorded at 1500 ppm. No number of nymph stage were recorded at all concentrations and periods. Moreover, activity of AChE was significantly inhibited at 1500 ppm, while activity of glutathione-S-transferase was significantly increased after 72 h. Finally, (SiO2-NPs) are effective against immature stages of T. urticae under greenhouse and laboratory conditions.
Afficher plus [+] Moins [-]Capabilities of Hyperspectral Remote Sensing Data to Detect Soil Salinity
2021
Abdelrahman Medhat Saleh | Mohammed Abd-Elwahed | Yasser Metwally | Sayed Arafat
The objectives of the current study were to investigate the opportunity of estimating soil salinity from hyperspectral data and identifying the most informative spectral zones for estimation. Electrical conductivity (EC) measurements of ninety topsoil samples (0–30 cm) collected from Toshka, Egypt, were used as data set. Analytical spectral device was employed to collect the reflectance spectral signatures of soil samples. Both linear regression and HSD Tukey’s analyses displayed that the SWIR1 and SWIR2 zones are the most suitable for soil salinity prediction while, blue, green and NIR were the wickedest. Moreover, EC estimation was better in case of lower soil salinity (0-2 dS m-1) than higher levels (8-1). Partial-least-squares-regression (ΡLSR) was employed to establish soil salinity prediction model using the training set of soil samples (n=75). The PLSR model was set up using the most informative wave bands (SWIR1 and SWIR2). The result showed that PLSR linear model gave a precise prediction of soil salinity (R2 = 0.93). The results revealed that employing reflectance values in SWIR in the model variables increases the precision of soil EC prediction.
Afficher plus [+] Moins [-]Management of Irrigation Water for Cucumber Crop by Using Drip Irrigation Systems under Greenhouse
2021
Esraa Masria | Abdelghany Elgandy | Khaled elbagoury | essam wasif
This study aimed to examine the consequences of three regimes for irrigation on cucumber crops and their growth indication, production, and water productivity under greenhouse cultivation. Cucumber seedlings were planted in May 2018 under a greenhouse condition. Three regimes of drip irrigation were examined, first 100%, 80%, and 50% of ETc namely T1, T2, and T3, respectively. The second regime was systems of drip irrigation (sur-face and sub-surface irrigation). Finally, the third was dripper discharge which used (2 l/h and 4 l/h). Results indicated clearly that the best production was under 80% ETc regime by 2 l/h dripper for surface and subsurface that was 10.1 and 11.2 ton/greenhouse respectively with IR 172 m3/season and the best regime by using 4 l/h was 50% ETc for surface and sub-surface respectively which was 11 and 11.5 ton/greenhouse with IR 216 m3/season which saved about half a quantity of irrigation water. On the other hand, the very best water productivity value (WP) was under 80% ETc was 58.7 and 65.4 kg/m3 under surface (S) and sub-surface (SS) drip irrigation respectively by 2 l/h dripper flow rate.
Afficher plus [+] Moins [-]Dissipation of Glyphosate and Glufosinate Ammonium in Soil and Weed Control in Citrus Orchards
2021
Amira Othman | Mohammed El-Zemaity | Walaa El-Sayed | Ahmad Hanafi | Khaled Ramadan
Glyphosate (GLY) and glufosinate-ammonium (GLUA) are broad-spectrum, non-selective, contact herbicides that are commonly used in fruit farms Achieving the separation and detection of glyphosate and glufosinate from soil samples by chromatography is a challenging task as they are ionic and highly water-soluble compounds. The aim of this study is conducted to determine the dissipation of GLY and GLUA applied at two dose levels in three-depth soils of orange orchards. The residues of GLY and GLUA were determined by the HPLC-UV detector. The residual detection limits of GLY and GLUA of the method were 0.03 and 0.05 ng/g in soil respectively. The obtained data indicated that GLY persistent in the soil is very short, only for 7 days, following applications of 1 to 2 kg/fed in the orange crop. GLUA dissipated in soil within 14 days of application, regardless of dose. The half-life (T/2) of GLY and GLUA were 1.68 and 1.42 days at 0 cm depth, respectively. There was no significant difference between the half-life of the two herbicides in soil at three depths. These results showed that GLY dissipation occurs rapidly in soil. However, GLUA was moderately persistent in soil. The two compounds tested showed a reduction of dry weight for four types of weeds after 14 days of recommended and double-rate application.
Afficher plus [+] Moins [-]Identification and Reconsidering Phylogeny of Some Aphid Species, (Hemiptera: Aphididae), Based on Molecular DNA Markers Using ISSRs-PCR Technique
2021
Ibrahim Adss | Reda Tabikha
Aphids are considered one of the most economically important insect pests worldwide. Successful pest management systems are based on accurate and rapid pest species identification. Traditional morphological identification of closed aphid species may be considered an inaccurate taxonomic process. To overcome the disadvantages of traditional morphological identification, molecular techniques, related to DNA markers and based on polymerase chain reaction (PCR), were approached by using nine ISSRs primers to identify and diagnose fifteen common aphid species that disperse in the Egyptian agroecosystem. The examined ISSRs primers could success-fully discriminate the tested aphid species that reflected 61.39% polymorphism among them. Moreover, four banding patterns were considered unique bands that could characterize three aphid species (Aphis gossypii, Aphis nerii and Myzus persicae). The highest genetic homology (84.9%) was observed between species Rhopalosipum padi and Schizaphis graminum. In addition, each of A. gossypii and Aphis citricola were also genetically homologous species. In contrast, species Aphis craccivora and M. persicae were analogous genetically with a low similarity percentile (59.8%). High genetic di-vergence was observed also between A. nerii and M. persicae. Two alternative molecular branching taxonomic keys were proposed by subjecting the five highest polymorphic ISSRs primers and 29 banding patterns with different molecular sizes.
Afficher plus [+] Moins [-]Relationship between fiber cotton grade and some related characteristics of long and extra-long staple Egyptian cotton varieties (Gossypium barbadense. L)
2020
M Hussein | A. El-Marakby | Afaf Tolba | Amal Mohamed | I Ebido
The materials used in this study were four commercial varieties of Egyptian cotton; two (Giza 86 and Giza 90) belonging to the long staple class and the others (Giza 88 and Giza 92) belonging to the extra-long staple category. Within each variety, nine lint cotton grades namely: Fully Good (FG), Good/Fully Good (G/FG), Good (G), Fully Good Fair/Good (FGF/G), Fully Good Fair (FGF), Good Fair/ Fully Good Fair (GF/FGF), Good Fair (GF), Fully Fair/Good Fair (FF/GF) and Fully Fair (FF) were used. Thus Fully Good (FG) is the top quality grade and the others are progressively lower; i.e. Fully Fair (FF) is the lowest grade. Fiber properties were measured by using the Cotton Classifying System Version-5 instrument (CCS-V5). Data collected for the following characteristics were: reflectance degree (Rd %), yellowness degree (+b), trash%, dust%, fiber fragments%, total trash%, No. of neps and Micronaire value. Mean squares due to all nine grades of long and extra-long staple cotton varieties in combined analysis were highly significant over seasons for all studied characters except yellowness (+b) and fiber fragments% in Giza 92. Highly significant mean performance values of four cotton varieties and nine lint grades for each variety for all studied characters, it became clear that there were significant genetically differences between studied varieties and fiber cotton lint grades within each variety. Gradually increased for yellowness degree, trash%, dust%, fiber fragments%, total trash% (trash, dust, fiber fragments) and number of neps, while gradually decreased for reflectance degree (Rd%) and micronaire value with significant level as transfer for all tested varieties from (FG) grade down to the (FF). All studied varieties showed highly significant negative correlation between fiber cotton grade with yellowness, trash, dust, total trash% and No. of neps, while highly significant positive correlation between fiber cotton grade with reflectance degree and micronaire value. Total trash% and micronaire value as well as reflectance degree and their interactions were the most contributing and influencing of fiber cotton grades. Also these properties and their joint effects are prevailing factors which affect the personal judgment of the grader at evaluating the cotton grade.
Afficher plus [+] Moins [-]THE DEMAND FOR EGYPTIAN CITRUS IN THE GLOBAL MARKETS
2020
Omnia Shahin | M. Rihan | Eman Fakhry | M. Abdelghafar
The trend currently in most countries of the world, whether developed or developing, is how to obtain the largest possible amount of gains in light of the state's available resources and the methods of production used and how to manage those resources in light of an investment climate consistent with those variables, and no country can live Isolated from all other countries in the world, whether that country is rich in resources and has a surplus in production and wants to spend it or it needs other countries to obtain a sufficient amount of a commodity that is sufficient for the needs of its population. In spite of the great export importance of Egyptian citrus crop and its occupation is the first in the list of Egyptian agricultural exports, and Egypt ranked third globally in its export, but its exports have been characterized by fluctuation and instability during the period (2018-2001), which leads to fluctuating returns from these masts, Which requires the necessity of identifying the determinants of external demand for these exports in various global markets to provide the necessary means for developing these exports and promoting them and maintaining their current markets and opening new markets for them and in light of the study problem and in an attempt to identify the most important variables Local and international influencing the demand for Egyptian citrus, and the study used a simultaneous multi-equation model, where he explained that the most influencing factors on the average Saudi per capita share of Egyptian citrus exports is the export price to Syria, and the export price to Jordan, as the value of "F" indicates the significance The statistically estimated equation is at the level of 0.05, and the adjusted coefficient of determination indicates that about 95% of the changes in the average per capita share of Egyptian exports are due to the above-mentioned independent variables. The results of the statistical analysis also showed that the most influencing factors on the average Russian per capita share The Egyptian citrus Dorat is the export price of Turkey citrus, and the average Russian per capita national income, as the value of "F" indicates the significance of the statistically equivalent equation at the level of 0.05, and the value of the adjusted coefficient of determination indicates that about 84% of the changes in the average per capita of exports The Egyptian citrus fruit of Russia is attributed to the aforementioned independent variables.
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