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Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi
2022
Sokkar, Mostafa | Ahmed, Eslam | Ibrahim, Ahmed | Mubarak, Manal | Nosseir, Mona
A field experiment was conducted in new reclaimed areas to improve avocado trees water productivity cultivated under deficit irrigation and mulching. The deficit irrigation treatments were 90, 80, 70, and 60% of reference evapotranspiration (ETo). Results revealed that The average water requirements during different avocado trees physiological growth stages were 613, 1509, 1755, 1391, and 632 m3 /fed for flowering to end of fruit set, fruit set to approximately 50% of the expected market fruit size, during the fruit growth stage, during the fruit ripening stage, and during the flower bud formation stage, respectively. These values represent approximately 10.4%, 25.6%, 29.7%, 23.6%, and 10.7% of the total yearly water requirement. The averages irrigation frequency were 2.45, 2.61, 2.72, 2.87, and 3.91day for 100, 90, 80, 70 and 60% ETo treatments, respectively. The highest crop water productivity value of 1.24 kg/m3 water was attained at 70% ETo followed by 1.18 kg/m3 water at 80% ETo while the least crop water productivity (1.06 kg/m3 water) was realized at 100% ETo. The crop water requirement of 5110 m3 /fed/year with high irrigation frequency is recommended for mulched sandy soil cultivated with avocado trees.
Afficher plus [+] Moins [-]Evaluation of Orius laevigatus as a predator of Bemisia tabaci In Vitro
2022
Salama, Nada | Emam, Azza | washahy, Kadry | Gaffar, Saad
This study determined the ability of Orius laevigatus to consume different stages of Bemisia tabaci at various densities. Additionally, the use of B. tabaci as food and its effect on the life cycle parameters and female fecundity of Orius predator developmental stages were investigated. The results showed that O. laevigatus could consume whitefly at various stages and complete its preimaginal and postimaginal stages, with B. tabaci eggs, nymph instars, and adults as the only available food source. The consumption and fecundity of O. laevigatus were influenced by feeding on different stages of B. tabaci. Furthermore, the females of this predator consumed more eggs, fourth nymphal instar, and adults than the first, second, and third instar nymphs of B. tabaci on a different density level. The mean numbers of consumptions at different stages of B. tabaci increased with increasing prey densities. The result simply that O. laevigatus can be used as a predator in the biological control of tobacco whiteflies.
Afficher plus [+] Moins [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect
2022
Mahmoud, Sobhy | Arafa, Yasser | abdel aziz, Ahmed Abo El-Hassan | El-Gindy, Abdel-Ghany
Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.
Afficher plus [+] Moins [-]Steroidal Saponins as Antioxidant and Alleviator of CCl4-Induced Oxidative Damage in Albino Rats
2022
Eliwa, Hala | Ibrahim, Mervat | EL-Sayed, Salwa | Abdelhamid, Mohamed
Liver toxicity is a common condition that can be induced by environmental pollutants. The present study explored the hepatoprotective activity of steroidal saponins extracted from the yam plant versus CC14-induced hepatotoxicity in albino rats. Twenty-five albino rats were classified into 5 groups. Rats of group (G1) were provided a basal diet and drinking water and served as un-treated controls. Other groups were administered CC14 orally twice a week at a dose of 400 mg/kg. The second group (G2) did not receive any further treatment and served as positive controls while rats in the groups G3, G4 and G5 were administered saponins (50,100 and 200 mg/kg body weight, respectively) for six weeks in the remaining groups. The hepatoprotective activity of saponins was assessed by measurement of liver enzymes, kidney function tests, malondialdehyde content, and antioxidant defense enzymes activities in serum of these rats. Saponins administration improved liver and renal function and significantly increased the activities of catalase, glutathione peroxidase (GSH-PX), glutathione reductase GSH-RD and superoxide dismutase SOD. These increases were linked to a considerable decrease in serum malondialdehyde levels, indicating that lipid peroxidation was being mitigated. Thus, the concentration of saponins (200 mg/kg) is the best concentration of protection against CC14-induced hepatic injury, improved liver and renal function, and reduced oxidative stress in rats.
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.
Afficher plus [+] Moins [-]Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Elhosieny, Asmaa | Zayed, Mona | Selim, Shawky | Abdel Aziz, Norhan
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It has the capability to enhance plant productivity. It acts as a mineral dissolution and growth promoter for plants under salt-stress conditions. The selected isolates revealed the general morphological and biochemical characteristics of Stenotrophomonas sp. All the isolates exhibited the highest growth density after 15 hr. at 30˚C, resistance to different levels of salinity, different pH levels, and different temperature degrees. Also, the isolates revealed their capabilities to solubilize phosphorus and potassium and to pro-duce different phytohormones. The isolate X.M9 exhibited the highest growth performance in the form of 1.376,1.326,1.292,1.053 and 1.059 OD in most salts’ concentrations compared to all tested isolates respectively. As well it (X.M9) exhibited the highest resistance to low temperatures 10 and 15oC being 0.917 and 1.354 OD respectively. The isolate X.M9 recorded the highest IAA of 83.73 mg/100ml compared to all the tested isolates. The isolate X.M9 were identified using 16 SRNA sequencing and submitted to the GenBank database under accession number No: OP050187 as Stenotrophomonas rhizophila.
Afficher plus [+] Moins [-]Isolation and Characterization of Probiotics from Various Food Products as Potential Human Food Additives
2023
Mohamed Ali, Fekria | Abdelhafez, Ahmed | Hassan, Enas | Abd-Elhalim, Basma
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 (DSM20336), and one yeast isolate as Saccharomyces cerevisiae (SaCe1 26S).
Afficher plus [+] Moins [-]Increasing of Amylopectin in Tetraploid Potato Desiree Cultivar (Solanum tuberosum L.) Via CRISPR/Cas9
2023
Ali, Nermin | Abdel-Salam, Mohamed | hanfy, aiman | Abd-Elhalim, Haytham | Ahmed, Nouh | Metry, Emad
Potato tuber starch characteristic is influenced by the ratio of amylose to amylopectin, which is affected by the granule-bound starch synthase (GBSS) gene. GBSS gene expression was decreased in the leaves of the Desiree potato variety utilizing genome editing using CRISPR-Cas9. Constructs encoding Cas9 gene and sgRNAs targeting GBSS gene were inserted into plant leaves using Agrobacterium-mediated transformation delivery. The results obtained lines with mutations in GBSS genes accounting for 21% of regenerated shoots. The identification of mutations within one base pair of the used guide sequence provided further evidence of the considerable similarity between the target region around the protospacer adjacent motif (PAM) position and the used guide sequence. Transforming DNA into potato leaves produced mutants that lacked the Cas9 gene. Using microscopic inspection of iodine-stained starch granules, the increase of amylopectin in the starch granules of editing potato tubers was evaluated.
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