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Water Distribution Uniformity for Turf Using a Simulation System Program
2024
shahenda el basha | khaled Elbagoury | Osama Ahmed Bedir
The study examines factors affecting sprinkler irrigation system distribution uniformity, including sprinkler type, operating pressure and computer software design. The pressures used were 1.5, 2.1, and 2.5 bar for spray nozzles 4A and 17A, and 1.7, 2, 2.5, and 3 bar for rotor nozzles 1 and 3. The results showed a strong correlation, with (R2) values of 0.996 and 0.973, between SIDUL-Program (Sprinkler Irrigation Distribution Uniformity for Landscape–Program) and Excel program with respect to coefficient of uniformity (CU) and distribution uniformity (DU) respectively, suggesting a strong correlation between the two programs. The HEDIA program validated the SIDUL–Program, revealing a 0.42% difference in CU values between the two programs for rotor nozzle 3, indicating also a strong correlation (R2 = 0.953) between the two programs. The results showed that DU for spray 4A at a pressure of 2.1 bar was 7.4%, higher than DU at a pressure of 1.5 bar; the CU for spray 17A was 11.9% higher, as supported by manufacturer specifications. The study concluded that calculating CU and DU using the SIDUL–Program is critical for assessing sprinkler performance in irrigation systems since it considers factors such as soil type, irrigation 1methods and location; in addition to being easy to use and accurate com-pared to other programs.
Afficher plus [+] Moins [-]L-Ascorbic Acid Improves Fruit Setting and Activates Antioxidant Enzymes in Tomato Plants (Solanum lycopersicum L.) Grown Under Heat Stress Conditions
2024
Abdalla Abdelmonaem | Zeinab Abdou | Hany Sror | Mohamed Aboul Fotouh
Heat stress is an environmental problem that can negatively impact tomato productivity by reducing fruit setting and disrupting pollen development. The present study aims to understand the molecular mechanism of heat tolerance induced by L-ascorbic acid. Plants were grown in the summer of 2022 (day and night temperatures were 34.4°C and 25.2°C respectively). The plants were divided into two groups: one was sprayed with L-ascorbic acid (0.5 mM) and the other served as a control. Growth parameters, antioxidant enzymes, proline, hydrogen peroxide, and malondialdehyde levels in the leaves were determined. Additionally, a molecular docking allowed understanding the interaction between the antioxidant enzymes and L-ascorbic acid. Results indicated that L-ascorbic acid increased antioxidant enzyme activities (catalase, peroxidase, ascorbate peroxidase, polyphenol oxidase), proline content, fruit setting and growth indicators (shoot and root fresh and dry weight). It also reduced hydrogen peroxide and malondialdehyde levels in tomato leaves. Furthermore, the in-silico analysis revealed that L-ascorbic acid binding energies toward antioxidant enzymes were similar to those of known activators. In conclusion, foliar application of L-ascorbic acid (0.5 mM) effectively mitigated heat stress effects, activating antioxidant enzymes and eliminating reactive oxygen species, ultimately resulting in increased fruit setting.
Afficher plus [+] Moins [-]Isolation of Proline-Rich Protein Gene from Potato under Drought Stress
2024
Heba Mohammed | Mohamed Abdel-Salam | Ayman Hanfy | Mervat Diab | Nouh Ahmed | Emad Metry
Drought stress is considered one of the main factors that reduce plant growth, development and production. Therefore, studying plants during drought stress is highly useful to discover the newly gained characteristics of plants. The potato is considered one of the most important crop with economic value in Egypt and over the whole world. The main target is the proline-rich protein extracted from potato plants under drought stress. A stress experiment was applied to two potato (Solanum tuberosum L.) cultivars Desiree and Diamante. The stress experiment was conducted by poly-ethylene glycol (PEG) 4000; the used water potentials were: zero (control), (PEG 2%), (PEG 4%) and (PEG 8%), after drought stress, the solutes accumulation in the two potato cultivars were determined. Increasing drought stress through elevating PEG decreased leaf area as well as shoot and root lengths. Incontorary, the chlorophyll and proline contents increased with increasing PEG treatments. The proline-rich protein gene was cloned to the pGEM-T Easy vector and was submitted to the gene bank to be used later for enhancing drought resistance in other cultivars.
Afficher plus [+] Moins [-]In Silico and In Vitro Assessment of Antiviral Activities of Licorice and Green Tea Extracts Against Tobacco Mosaic Virus
2024
Alshymaa Ahmed | Khalid El Dougdoug | Lina Amin | Atef Sadik
Using integrated in silico and in vitro experiments, the antiviral capabilities of green tea and licorice extracts were evaluated against the tobacco mosaic virus (TMV). It was noted that the number of induced necrotic local lesions of TMV decreased by increasing extract concentrations and thus it is considered concentration dependent on the extracts’ active compounds. Properties of eleven compounds belonging to licorice and green tea were obtained from databases to examine their activities in silico. A molecular docking simulation was performed between these agents and the protein coat of the tobacco mosaic virus (TMV). The highest effective compounds were glycyrrhetic acid, liquiritin and EGCG. ADMET studies revealed good overall properties of nine non-toxic compounds based on their predicted pharmacokinetic, physicochemical, drug-likeness and toxic properties. Based on docking energy and mode of interaction, these compounds showed strong binding with the protein coat of TMV. The antiviral effect may be due to the most effective compounds with the highest affinity namely glycyr-rhetic acid, liquiritin and isoliquiritin. As a conclusion, the promising value of our titled extracts is the anti-TMV activity and pharmacokinetic and physicochemical properties of their active constituents.
Afficher plus [+] Moins [-]Isolation and Characterization of Probiotics from Various Food Products as Potential Human Food Additives
2023
Fekria Mohamed Ali | Enas Hassan | Ahmed Abdelhafez | Basma Abd-Elhalim
In this study, human-safe lactic acid microorganisms (LAM) were isolated from food samples to be used as potential additives for human food. Samples from various food sources (artisanal cheeses, fermented chickpeas, fermented rice, natural yogurt, pickles, and raw milk) were used to inoculate de Man, Rogosa, and Sharpe (MRS) and malt agar plates, which were incubated at 30°C for 48 h or 37°C for 72 h to isolate lactic acid bacteria and yeast, respectively. Out of 120 isolates (85 bacteria and 35 yeast), 75 isolates showed γ-hemolytic activity and were considered “Generally Recognized As Safe” (GRAS) isolates. After testing their growth rate under the gastrointestinal tract (GIT) conditions, including acidic pH and specific bile salt concentrations, we selected 30 isolates. Then, we evaluated the fermentative abilities of these 30 isolates on nine types of carbohydrates, their total acidity, and their antagonistic activity against five human pathogens. Based on the results of these tests, four isolates were selected for identification using the Biolog program and 16S rRNA sequencing for bacteria and 18S rRNA sequencing for yeast and found to be Bacillus bingmayongesis (FJAT-13831), Lacticaseibacillus paracasei (R094), Pediococcus pentosaceus (DSM 20336), and one yeast isolate as Saccharomyces cerevisiae (SaCe1 26S).
Afficher plus [+] Moins [-]The Potential Efficiency of Lactobacillus farraginis Isolated from Ruminants with a View to be Used as Animal Probiotics
2023
Mona Zayed | Dalia Abd El-Fattah | Rateb Abbas | N. El-Bordeny | Sherif Edris
Probiotics refer to 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 37oC, and moving toward neutrality and alkalinity of the media. Strain Lactobacillus farraginis MD_A11 revealed the lowest decrease 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 [-]Effect of Foliar Spraying with Pink Pigmented Facultative Methylotrophic Bacteria on the Growth and Productivity of Strawberry
2023
shadia Ismail | Fafy Mohammed
Pink-pigmented facultative methylotrophic bacteria (PPFM) isolated from cotton leaves was identified based on phenotypic and genotypic characteristics as Methylobacterium rodiotolerance. Two field experiments were conducted to investigate the effects of PPFM, methanol (10 and 30%) and a combination of bacteria and methanol on the growth, fruit quality, and yield of two strawberry cultivars (Florida and Festival). The main differences between the two cultivars are greater foliage fresh weight and early yield in cv. Florida while Festival cv. had a higher total yield per plant and greater anthocyanins and ascorbic acid contents. The greatest vegetative growth, dry matter percentage, potassium content, and carbohydrate content besides the earliest yield per plant were observed following spraying with PPFM or PPFM mixed with 10% methanol. Spraying with PPFM resulted in the highest total yield per plant, highest yield per feddan, and fruit quality. Spraying cv. Florida with PPFM resulted in the best early yield while spraying cv. Festival with PPFM resulted in the highest total yield and fruit quality. Spraying with PPFM appears to be the most efficient treatment for enhancing the total yield of Festival cv. by an average of 23.02 and 24.06 tons per feddan in the first and second seasons, respectively.
Afficher plus [+] Moins [-]Molecular Identification of Some Rhizobium and Serratia Isolates as Potential Producers of Indole-3-Acetic Acid
2023
Shaimaa Sello | Ashraf Abdel Razik | Samir Ibrahim | Sawsan Elateek
In order to reduce the use of chemical fertilizers, the use of biological inoculants has been increased. Beneficial microorganisms are used to increase crop yields by stimulating plant growth through the production of phytohormones. In the present study, Indole Acetic Acid (IAA) production was analyzed in 18 bacterial isolates with Plant Growth-Promoting (PGP) capabilities; 15 of these isolates were Rhizobium, and three were Serratia. All isolates have been characterized morphologically and biochemically, and their IAA production in the presence of tryptophan, a precursor for IAA biosynthesis, has been evaluated. IAA production was detected using the Salkowski reagent with CT-2200 spectrophotometer at 530 nm. The levels of IAA production varied between the different isolates. The top two IAA producers were selected for genetic identification using 16SrRNA primers (27F and 1492R). One of the Rhizobium isolates (NRC-R2) shared 95% sequence similarity with Rhizobium sp., according to a Blastn search in GenBank and Rhizobium leguminosarum, whereas the Serratia isolate (Ain Shams Center for Genetic Engineering and Biotechnology (ACGEB)-S2 was 99.5% similar to Serratia sp. Accordingly, these two isolates could serve as biological sources for IAA.
Afficher plus [+] Moins [-]Predicting and Optimizing Tillage Draft Using Artificial Network Technique
2023
Yasmin Shehta | Nabil Awady | Abdel-Fadil Kabany | Mohammed Abd-Elwahed | Waleed Elhelew
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 opti-mize the performance of the tillage process. The ANN-modeled multilayer perceptron network with a backpropagation learning algorithm and momen-tum 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, re-spectively. Momentum term and learning rate were 0.00003 and 0.9 respec-tively. 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 den-sity and depth were the main determinants of the draft. The evaluation of the developed model for chisel, moldboard, and disk plow gave satisfactory re-sults 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 [-]Residue Assessment of Bifenazate, Spirodiclofen and Abamectin in Strawberry Fruits Under Field Conditions
2023
Eman Abdelmaksoud | Walaa Elsayed | Shoukry Elrefai | kadry mahmoud | Khaled Ramadan
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.
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