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Description of Leafhopper, Hebata (Alboneurasca) decipiens (Paoli, 1930) and Its Transmitting Phytoplasma Infesting Sugar Beet Plants
2023
Ibrahim, Heba | Abdelrahman Emam, Azza | Bondok, Ahmed | Ahmed, Magdy | Abd-Elraheem, Amro
The second sugar crop of sugar production after sugar cane world-wide is sugar beet (Beta vulgaris L.). This plant is subjected to the infestation of several insect pests that cause considerable damage, especially leafhoppers, that can transmit phytopathogens (e.g., phytoplasma). In this work, we identified and described the leafhopper, Hebata (Alboneurasca) decipiens, in addition to detection and molecular identification of Candidatus Phyto-plasma that was transmitted by this leafhopper on sugar beet plants from naturally infected sugar beet plants to an uninfected one. The 16S rDNA gene from phytoplasma was amplified by a nested polymerase chain reaction (PCR) assay and directly sequenced using specific primer pairs DNA fragments. The resulting sequences were analyzed and compared with another phytoplasma sequence available at GenBank sequences performing BLAST using DNAMAN.
Afficher plus [+] Moins [-]The Potential Efficiency of Lactobacillus farraginis Isolated from Ruminants with a View to be Used as Animal Probiotics
2023
Zayed, Mona | Abd El-Fattah, Dalia | Abbas, Rateb | El-Bordeny, N.
Probiotics refer to the microorganisms that exhibit a beneficial effect on the animals’ health through intestinal microbial balance. This investigation intends to identify and define the probiotic characteristics of Lactobacillus strains isolated from the digestive systems of ruminants. Bacterial strains were isolated purified and characterized based on morphological and biochemical characteristics. The isolates were identified using the 16S rRNA gene partial sequencing method. Most of the strains exhibited a decrease in the growth by increasing the concentration of the bile salt, NaCl, increasing the temperature over 37˚C, and moving toward neutrality and alkalinity of the media. Strain Lactobacillus farraginis MD_A11 revealed the lowest de-crease in the growth percentage when subjected to different bile salt concentrations of 5.96, 6.61, 6.85, 7.40, 7.53, and 7.64%, NaCl% concentrations of 1.40, 5.62, 6.48, 7.36, 7.39, 7.41, 7.42, 7.28, and 13.76%, raising the temperature over 37oC being 4.19 & 3.945%, different pH levels as compared to control, and it recorded the lowest medium pH after the third day being 4.20 with titrable acidity of 0.32%. Strain Lactobacillus farraginis MD_A11 could be recommended as a probiotic feed additive for ruminants to improve their growth performance and productivity.
Afficher plus [+] Moins [-]Residue Assessment of Bifenazate, Spirodiclofen and Abamectin in Strawberry Fruits Under Field Conditions
2023
Abdelmaksoud, Eman | Elsayed, Walaa | Elrefai, Shoukry | mahmoud, kadry
The dissipation behavior of three pesticides, bifenazate, spirodiclofen and abamectin was studied in strawberry fruits using a modified QuEChERS extraction technique. The residues of the tested acaricides were determined under field conditions after 1 hour (zero days), 1, 3, 7, 14, and 21 days. The maximum residue limits (MRLs) were 2, 2, and 0.15 mg/kg for bifenazate, spirodiclofen and abamectin, respectively. The strawberry fruits could be used safely after 15 days from bifenazate spraying and after 3 days from spirodiclofen spraying. The concentration of abamectin after 21 days did not reach MRL. The half-life values (t1/2) of bifenazate, spirodiclofen, and abamectin in strawberry fruits were 0.99, 0.86, and 5.7 days, respectively.
Afficher plus [+] Moins [-]Effect of Gamma Radiation on Ephedrine and Pseudoephedrine in Callus and Suspension Cultures of Ephedra alata
2023
Abdelsalam, Naglaa | Abd El-Aal, mona | Aboul Fotouh, mohamed | Reda, mohamed | Safe, Ibrahim
Ephedra is the most widely and largest widespread genus in the Gnetopsida, a subgroup of the gymnosperms. This research was done to find out how gamma radiation affected the in vitro growth of callus and suspension cultures. In addition, the effect of gamma rays (γ-rays) on the ephedrine and pseudoephedrine concentrations was evaluated through HPLC analysis. The cell suspension and callus cultures were formed on Murashige and Skoog's basal medium (MS) supplemented with 0.5 mg/l kinetin (Kn), and 3 mg/l of 2, 4-dichlorophenoxy acetic acid (2,4-D) and exposed to variable gamma radiation doses (0, 5, 10, 15, 20, 25 and 30 Gray). Highly significant differences in both fresh and dry callus weights were recorded due to the effect of gamma rays (γ-rays). The findings demonstrated that in the cell suspension and callus cultures, 15 Gray achieved the highest fresh and dry weights when compared to the control. Similarly, the highest concentrations of ephedrine and pseudoephedrine were found in suspension and callus cultures compared to control at 15 Gray.
Afficher plus [+] Moins [-]A Theoretical Analysis of the Plate Heat Exchanger's Ideal Operating Conditions for Producing Soybean Milk
2023
Salama, Omnia | Sorour, Manal | Anwer, Ashrf | Abd El-salam, Mostafa
Heat exchanger optimization is a very efficient thermal design inquiry. The goal of the research is to determine an optimal channel flow velocity as well as an optimal total plate number based on overall information on the effectiveness of employing chilled water to cool soybean milk. Heat transfer coefficient, Prandtl number, Reynolds number and pressure drop measurements were applied for milk and water. The rheological properties of soybean milk have been investigated at various temperatures (5, 10, 30, 50, 70 and 90 °C). The operational circumstances of PHE in soybean procedures were investigated at different numbers of plates, flow rates and flow velocities. Based on the present study, total substances showed non-Newtonian pseudoplastic conduct in any respect at any temperature and the power law model has a decent correlation. The cost estimation of the plate heat exchanger was observed at the lowest flow velocity of (2.25) m/s and number of plates is 17.
Afficher plus [+] Moins [-]Phylogenetic Evolution of Egyptian Goat Breeds “Capra Hircus” Based on Mitochondrial DNA D-Loop Sequence
2023
Bherey, Eslam | Hassan, Heba | Ellbadawy, Adel | El_Maghraby, Mahmoud | Moghazee, Mona
The population genetic and molecular evidence of the Arabian goat breed's phylogenetic standing (Capra hircus) is misunderstood, and little is known about genetic diversity in this species. Despite their importance in producing meat and milk, as well as their capacity to endure difficult conditions with little access to food and water, goats are the most common animal in Arab countries. We investigated the phylogenetic history and demographics of domestic goats by sequencing a hypervariable segment of the mtDNA reference region for Baladi, Demuscous, and Zaraibi breeds, as well as sequences retrieved from 16 Arab countries. Three significantly divergent lineages associated with Africa and the Middle East were identified through phylogenetic analysis of the investigated strains of Egyptian goats' mtDNA D-loop region. All Egyptian goats were allocated to lineage A, which is made up of 445 different haplotypes, including Egyptian and Arabian goats. Diversity in haplotypes and in nucleotides for each Arabian goat population was calculated separately and estimated to be 0.99835 and 0.02576, respectively. Finally, we suggest that all goat lineages descend from a single clan. The ancient world's migration and travel may have influenced goat diversity, implying that goats had multiple matrilineal forebears
Afficher plus [+] Moins [-]Evaluation of Certain Synthetic and Natural Pesticides Against Whitefly Bemisia tabaci (Genn.) on Green Bean and Effect on Honeybee Apis mellifera L.
2023
Ahmad, Sharihan | Abdelghany, Walaa | Ahmed, Ahmed | Abdelmegeed, Sawsan
The green bean crop (Phaseolus vulgaris) is infested with many insects such as whiteflies (Bemisia tabaci). An investigation was carried out to study the insecticidal activity of whitefly (Bemisia tabaci), five pesticides were used, namely Thiamothoxam, Sulfoxaflor, Spirotetramat, Pymetrozine, and Flonicamid, and three commercial natural pesticides, namely Superrego, Topnine, and Bernastar. Pesticides and natural pesticides were sprayed during the two seasons of 2020 and 2021. The obtained results in terms of the reduction rate of the insects' number were as follows: The highest rate of reduction appeared in Thiamothoxam and Sulfoxaflor treatments, where it reached above 80%, while the other pesticides were in the range of 40% to 60%, and the lowest reduction rate was 34.33% and 36.00 % for Bernastar during season 2020 and 2021 respectively. When evaluating the toxicity of these pesticides and natural pesticides against honeybees (Apis mellifera), the pesticides did not reveal any toxicity to honeybees, except for Thiamothoxam, Sulfoxaflor, and Superrego The LC50 and LD50 values against honeybees were 0.2 ppm and 0.000005µg/one honeybee for Thiamothoxam, 4.5 ppm and 0.0001125 µg/one bee for Sulfoxaflor, and 0.95 ppm and 0.00002375 µg /one bee for Superego respectively.
Afficher plus [+] Moins [-]Effect of Pruning Levels on Yield and Fruit Quality of Melody (Blagratwo) Seedless Table Grape Cultivar
2023
Ali, Ali | Abdle Hamid, Nazmy | shaddad, Amin | Nasser, Mohamed
Three years old uniform vines for cv. "Melody syn. Blagratwo" seedless table grape were selected, and three levels of bud load were trimmed, namely 60, 72, and 78 buds/ vine. The findings revealed that vegetative growth traits, characteristics of yield and bunch quality were significantly affected by all different pruning levels of cane length in both seasons of this study. Highest bud load vines (78 buds/vine) produced the greatest yield and cluster number but had a negative effect on the percentage of bud behavior, shoot thickness, shoot length, weight of annual pruning (Kg/vine), cluster and berry quality parameters. In contrast, lowest vine bud load (78 buds/vine) had a better bud behavior, vegetative growth traits, cluster characteristics and berry characteristics but both bunch numbers and yield were reduced. In addition, vines pruned with bud load of 72 buds per vine significantly showed the best outcomes, since it successfully struck a balance be-tween features of vegetative growth, yield, cluster and berry physical and quality attributes in both seasons.
Afficher plus [+] Moins [-]Predicting and Optimizing Tillage Draft Using Artificial Network Technique
2023
Shehta, Yasmin | Awady, Nabil | Kabany, Abdel-Fadil | Abd-Elwahed, Mohammed | Elhelew, Waleed
Machine learning models, Artificial neural network, Tillage performance, Energy needs, draught Tillage as one of the agricultural practices consumes the largest amount of energy, which reflects on the total production cost. The artificial neural network (ANN) technique was utilized in the current study to optimize the performance of the tillage process. The ANN-modeled multilayer perceptron network with a backpropagation learning algorithm and momentum term was used by the PYTHON program. The ANN inputs were the implement type, soil texture, moisture, bulk density, width, speed, and depth. The draught was the output (kN). Five layers composed the ANN model's optimal configuration (13-64-16-4-1). The linear and rectified linear units (ReLU) functions were utilized with hidden layers and the output layer, respectively. Momentum term and learning rate were 0.00003 and 0.9 respectively. The iteration number was 1000 epochs and stopped at 290 epochs. The coefficient of determination in the test datasets was high (0.92) while the difference between actual and predicted output was low (2.08). Bulk density and depth were the main determinants of the draft. The evaluation of the developed model for chisel, moldboard, and disk plow gave satisfactory results of 0.985, 0.924, and 0.917. In comparison to the ANNs, the regression model's correlation coefficient for predicting draught force was the lowest (0.373).
Afficher plus [+] Moins [-]Partial Gap-Filling of the Nile Tilapia Oreochromis niloticus Draft Genome
2023
Zoghly, Hala | Rashed, Mohamed | Magdy, Mahmoud
Nile tilapia is a freshwater fish of African origin, with productive and economical characteristics affecting global fish markets. The Oreochromis niloticus reference genome has a diploid set of 22 linkage groups (LGs) in addition to ungrouped sequences. A total of 42,622 genes have been identified, but 550 genomic gaps may include more. Our study focused on some of these genomic gaps, where appropriate primers were designed and then multiplied through the polymerase chain reaction (PCR) technique. From local samples, DNA was extracted and amplified with the new primers. Successful amplicons were sequenced and annotated using available bioinformatics tools. Five assessed sequences were annotated, of which three were newly predicted in O. niloticus, as mucin 1-like, and KLR genes, and SATB region. The other two sequences belonged to grid2 and trpm7 which were previously predicted. Although individual attempts to identify genomic gaps are not feasible in filling the large lack of information on the Nile tilapia genome, a good number and valuable new information has been reached. How-ever, the following plan showed many technical problems, more time, effort, and cost that could be avoided by suggesting the application of another technique, such as whole-genome sequencing, mapping, and assembly.
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