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Greenhouse and Laboratory Evaluation of The Efficiency of Green Silicon Dioxide Nanoparticles Against Tetranychus urticae (Koch) Texte intégral
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 [-]Detoxifying Enzymatic Activity and Insecticide-Resistance Gene Expression in Field Populations of Pink Bollworm, (Pectinophora gossypiella (Saund.)) Texte intégral
2021
Rabab Desouky Alam | Amgad Sobeiha | Abdel-Aziz Khdir | Naima Alsenosy
A study was conducted to assess two enzyme detoxifying activities and insecticide-resistance gene expression quantitation using real-time (PCR). Four populations of pink bollworms were compared with the baseline laboratory strain. Field populations showed higher levels of enzymatic activity, glutathione-S-transferase and β–esterases, than those of the laboratory strain. The amplification curves scored a cycle threshold (Ct) value of 25 for the ribosomal protein subunit7 (rps7). For the BtR gene, the Ct values of analyzed biological groups ranged from 20 for the laboratory strain to 24 for the Fayoum group. For Cad1, the Ct values ranged from 19 for laboratory strain to 23 for Fayoum and Qalubia populations. Therefore, the present work introduces a method for the challenge of monitoring resistance to Bt toxins in crops which requires, according to the IPM (Integrated Pest Management) program, a wise insecticide application.
Afficher plus [+] Moins [-]Management of Irrigation Water for Cucumber Crop by Using Drip Irrigation Systems under Greenhouse Texte intégral
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 [-]Impact of Bio- and Chemical Fertilization on Growth, Yield, Essential Oil and Chemical Composition of Fennel (Foeniculum vulgare Mill.) Plant Texte intégral
2021
Omniea Allam | Soheir Hassan | Awad Kandil | Ahmed Abdel Hamid | Abdallah Korayem
A pot experiment was carried out in seventeen levels of fertilization to evaluate the effect of the bio-fertilizer mixture alone or in combination with chemical fertilizer (NPK) on Fennel (Foeniculum vulgare Mill). Bio-fertilizer was a mixture of Azotobacter chroococcum, Bacillus circulans and Vesicular-arbuscular mycorrhiza. Results indicated that the use of bio-fertilizer at 3.75 ml/pot four times with 25% of NPK gave the highest significant values of vegetative growth, yield parameters, and NPK uptake; how-ever, fertilizing with bio-fertilizers without NPK application showed the lowest significant values in the two experimental seasons. The same addition of bio-fertilizer gave the highest significant values of total microbial count of soil and increased cumulative CO2; whereas the addition of 100% NPK gave the lowest significant values in both seasons. The full dose of NPK significantly increased volatile oil percentage while the addition of bio-fertilizer only significantly decreased it in both seasons. GC analysis of essential oil showed that the highest percentage of anethol (12.77 %) was obtained by applying 3.75 ml/pot bio-fertilizer added one time + 25% NPK and de-creased estragole (72.78%).
Afficher plus [+] Moins [-]Turmeric Extracts as a Protective Natural Compound Against Hepatotoxicity Induced by Lead Nitrate in Male Albino Rat Model Texte intégral
2021
Abd el-Fattah Abd el-Fattah | Medhat Abozid | Kamal Mahmoud
Excessive exposure to lead may damage the liver by increasing oxidative stress, leading to many serious diseases. Dietary antioxidants may protect the liver from damage. Therefore, the effect of ethanolic and aqueous turmeric extracts against lead-induced liver damage was evaluated by estimating liver function and antioxidant/oxidative stress biomarkers. Forty rats were divided into group (A) served as the control and group (B) was treated with 93 mg/kg b.wt. lead nitrate; while group (C) and group (D) were treated as group B in addition to 400 mg/kg b.wt. of turmeric aqueous and ethanolic extracts, respectively. Group B showed a significant increase in the activities of alanine transaminase by 10 folds, aspartate transaminase by 9 folds, alkaline phosphatase by 3 folds and the level of malondialdehyde by 10 folds, while showed a significant decrease in albumin by 60%, total protein by 54.5%, and superoxide dismutase by 80.5%, catalase by 75% and glutathione by 71.6% in comparison with those of the control group. On the other hand, turmeric treatments (groups C and D) led to a readjustment of levels for such biomarkers. Collectively, these results demonstrate the potential of turmeric extracts (particularly the ethanolic extract) to improve the fatal effect of lead in a rat model.
Afficher plus [+] Moins [-]Identification and Reconsidering Phylogeny of Some Aphid Species, (Hemiptera: Aphididae), Based on Molecular DNA Markers Using ISSRs-PCR Technique Texte intégral
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 [-]Design of Sprinkler Irrigation Systems Using an Expert System Program Texte intégral
2021
Mohamed Alashram | Khaled elbagoury | Said Shaaban | Ahmed abdel-aziz
In this research, a rule-based expert system named EFSIS-ES (Engineering Factors of Sprinkler Irrigation System -Expert System) had been built, verified and validated. Therefore, the aims of this research were to build, verify and validate an expert system for making a decision for the normal user to maximize system efficiency of sprinkler irrigation. The inputs data included location data, climate data, pump data, crop data, soil data and sprinkler system data. The outputs of the expert system were number of the sprinklers on a lateral, number of laterals in the irrigation system, length of each lateral, main line length, irrigation frequency, required pump power, total dynamic head (TDH) and pump discharge output. Results showed high correlation (R2 = 0.9927) between the EFSIS-ES program and the designed spreadsheet in regard to irrigation frequency. It could be indicated high correlation (R2 = 0.9999) between the EFSIS-ES program and the designed spreadsheet regarding pump power. The regression coefficient (R2) was 0.9983 between EFSIS-ES program and SSSDPS Expert regarding total dynamic head (TDH). It could be indicated high correlation (R2 = 0.9979) between EFSIS-ES program and SSSDPS Expert regarding pump discharge output.
Afficher plus [+] Moins [-]Improvement of Irrigation Efficiency by Developing Surface Irrigation System Texte intégral
2021
Marwa Mohamed | Mahmoud Hegazi | essam wasif | Osama Ahmed Bedir
The experiments were Carried out in Biahmu Village at Al-Fayoum Governorate, Egypt during the two winter seasons of 2018/2019 and 2019/2020, on wheat crop to (cv. Gemmiza 11) evaluate the traditional surface irrigation system "TSIS" and the improved surface irrigation system "ISIS"(terrace), under laser leveling with two slops (S1≈ zero% and S2 ≈ 3%). The evaluation parameters included; reduction in land loss "LL", the roughness coefficient of marwa-walls, water efficiencies (i.e., water conveyance efficiencies "WCE", water application efficiencies "WAE" and water storage efficiencies "WSE"), yield productivity "Yp", total applied water and water required, irrigation water productivity "IWP" and times of water advance, recession and opportunity. The results concluded that improving traditional marwa, led to reduction in land loss by 49.46% from the area of marwa, and "WCE" increased by 83.17% in improved Marwa "IM" the compare to Traditional Marwa "TM. It was observed that on the efficiency of water added to the field irrigated by "TM". The highest level of water productivity (1.79kg wheat/m3 water) was achieved in "IM" at a level of 3%. Advanced time "T.Adv" (min) decreased at 50, 50.77, 27.6, 20.75, and 17.17% and 30.9, 40.51, 22.8, 10.89 and7.05% for "TL and IL" by sloping to "S2".
Afficher plus [+] Moins [-]Efficiency of Three Bacterial Strains Against Tetranychus urticae Koch (Acari: Tetranychidae) Under Laboratory Conditions Texte intégral
2021
Heba Emam
This study was conducted to evaluate the efficiency of three bacterial strains Pseudomonas aeruginosa, Bacillus subtilis and Lysinibacillus spaericus against adult females of Tetranychus urticae Koch using spraying and dipping techniques with concentrations (101, 103, 105, 107 cfu. ml-1). The mortality percentages were calculated and numbers of each stages resulting from the live treated females were recorded. The symptoms that appear on treated female's mites as a result of death under laboratory conditions were recorded and photographed. The results revealed that, P. aeruginosa caused the highest mortality percentage of adult females T. urticae 100% after 72h at concentration 107 cfu. ml-1 by spraying application. Whereas the mortality percentage which recorded by the dipping technique was 54.58±1.71. B. subtilis also, was recorded increased the average mortality percentage of female T. urticae as it reached 73.33±2.67 in spraying technique compared 41.25±2.08 in dipping technique. While in L. spaericus recorded 62.08±3.41 mortality (%) in spraying technique but at dipping technique the mortality was 27.50±1.61. A sharp decrease was shown in number of stages resulting from lived treated females of T. urticae with P. aeruginosa by four concentrations 101, 103, 105 and 107 by using spraying technique and the life cycle was stopped at the larval stage only at concentration 101 and were not changed into the nymphal stage. While with dipping technique a slight increase in the average number of stages resulting from the adult living females treated with the previously aforementioned concentrations of bacteria P. aeruginosa. The present study cleared that application of bacteria strains on T. urticae adult females either by spraying or dipping techniques lead to some deformations such as, swelling of the body, then fluids exit followed by complete dryness of the body and forward protrusion of the podosoma region and finally death of the adult females
Afficher plus [+] Moins [-]Effect of Using Probiotics (ZADO®) on the Productive Performance of Nile Tilapia Fish (Oreochromis niloticus) Texte intégral
2021
Shahinaz Abdelaty | Mohammed Osman | Hany Gado | Nagwa Maghraby | Zeinab Aly | Ali Elnadi
The research was performed at the Department of Animal Production's fish laboratory, National Research Center, Dokki, Egypt. The research was conducted to assess the impact of commercial powder probiotic (ZADO®) on growth efficiency of Nile tilapia mono-sex fish (O. niloticus), which were fed on basal experimental diet (the control group)and other 4 experimental diet, which was the basic diet augmented with 0.25,0.5,0.75 and 1% of ZADO® for T1, T2,T3,T4 andT5, respectively. The Five experimental treatments were performed in three replicates each, the experimental aquaria were part of closed recirculating system, where environmental parameters were kept constant throughout the experimental period. Fifteen aquaria 60 × 40 × 30 cm, width, depth, and height, respectively each was stocked with 15 fish. The mean individual initial body weight (4.04 g/fish) was recorded at the start of the experiment. All fish in each aquarium throughout the entire experimental period were weighed every two weeks. The experimental fish were fed 32 % crude proteinbased diet for (98 days). The daily feed allowances were calculated as 5% of fish body weight and were divided into 3 portions fed at 8 am, 12 pm and 4 pm. The Results of the experiment indicated that T2 had the largest significant (P<0.05) final body weight (FBW g/fish), average weight gain (AWG, g/fish), specific growth rate (SGR % day), feed conversion ratio (FCR), feed efficiency ratio (FER) and protein efficiency ratio (PER) among all the experimental groups. In addition, no substantial variations (p > 0.05) were found in protein productive value (PPV). Although significant effects (p <0.05) have been reported in fish body crud protein (CP) and fat (EE) in T2. By increasing ZADO levels in experimental diets higher than 0)25% no significant effect were observed.
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