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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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]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
Mostrar más [+] Menos [-]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.
Mostrar más [+] Menos [-]Impacts of Natural and Supplementary Foods on Some Biochemical Activities in the Bodies of Honeybee Workers
2022
Sayed, Sobhia | Elsherif, Mohamed | Mahmoud Basuony, Adel | Ghazala, Naglaa
The experiments were conducted during seasons (summer, au-tumn, winter, and spring) 2020–2021 to study the activities of invertase, adenosine triphosphatase (ATPase), and alkaline phosphatase (AlkP) as well as the determination of total proteins. These activities were determined in the bodies of adult honeybee worker, Apis mellifera, (house and forager bees) after feeding on three different diet groups (A) pollen cake, (B) supplementary diet and (C) control group during the four seasons. Group (A) received 50 g pollen cake + 250 ml honey syrup (2 honey: 1 water)/colony/three-day intervals, group (B) received 50 g Brewer’s yeast chickpea cake fortified with 4.2% pollen + 250 ml sugar syrup (2 sugar: 1 water) while group (C) received 250 ml sugar syrup (1 sugar: 1 water) only. Results indicated that the highest increase in total proteins was found in group B during the autumn season with house bees. Invertase activity was high in group A during the summer season with forager bees. The highest ATPase activity was observed in group B during the spring season with house bees, whereas the highest AlkP activities were found in group A during the autumn season with house bees.
Mostrar más [+] Menos [-]Impact of Maltodextrin and Inulin on Synbiotic Fermented Milk Production
2022
El-Komaily, Reda Mohamed | Elbatawy, Osama | Aumara, Ihab
The influence of maltodextrin or inulin added as a prebiotic on the survival of various strains of probiotics in synbiotic fermented milk along cold storage was investigated. Synbiotic fermented milk was prepared using several probiotic strains (Lb. helveticus and Lb. acidophilus) and 2% maltodextrin or inulin and compared with traditional yoghurt starters (Lb. delbrueckii subsp. bulgaricus and Str. thermophilus). Synbiotic fermented milk samples were stocked at 4°C then the chemical, microbiological and sensory characteristics were estimated. Starter culture strains showed no significant effect on dry matter and ash contents in various synbiotic fermented milk samples during storage. However, starter culture type, fortification by maltodextrin or inulin, and storage period significantly influenced the acidity, total and soluble nitrogen contents (SN\TN), acetaldehyde, diacetyl contents and viscosity in various synbiotic fermented milk samples. In addition, fortification of maltodextrin or inulin significantly influenced the survival of yoghurt starter culture strains, Lb. helveticus and Lb. acidophilus strains. The counts of probiotic strains used in all treatments of synbiotic fermented milk survived well and were above the recommended minimum levels (106CFU/ mL) during a storage period.
Mostrar más [+] Menos [-]Performance and Stability of Promising Bread Wheat Lines for Grain Yield and Yield Components
2022
Badr, Asmaa | Saleh, Samir | Mohamed, Amal | El-Gabry, Yasser
The present study was conducted to evaluate 50 wheat genotypes for their productivity and stability under eight environmental conditions. Wheat genotypes were sown at two planting dates under two nitrogen fertilization treatments during the winter seasons of 2018/2019 and 2019/202. The analysis of variance showed that the mean squares of genotypes, sowing dates, and nitrogen fertilization treatments were significant for the number of spikes/plants, the number of kernels/spikes, 1000-kernel weight, and grain yield/plant. The results showed that sowing at the favorable date using 80 kg N/fed increased all studied traits. This study revealed that line numbers 9 and 10 exhibited general adaptability across different environments; hence, these lines are considered promising and could be exploited in breeding programs for wheat improvement.
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