خيارات البحث
النتائج 101 - 110 من 1,133
Effect of Fungicide, Salicylic Acid, Henna Powder and Propolis on Silkworm Larvae Infected with Aspergillus spp.
2021
Eman Abd El-Razek | Madiha A Rizk Rizk | Youssef Abdallah | Khadiga Abou-Taleb | sawsan abdelmegeed
Mulberry silkworm, Bombyx mori L. is in-fected with many diseases. In this work, two fungi species, Aspergillus fumigatus and As-pergillus flavus, were isolated from the in-fected B. mori larvae during rearing process. The morphological symptoms were the same for both fungi and appeared from newly hatched larvae until moth formation. In larvae, black spots of both fungi species appeared eve-rywhere on the body, then these spots extended and eventually larvae died, and fragments of the fungus came out from the spots. The only one difference between the two fungi, is that symptoms of A. fumigatus appeared four days earlier than those of A. flavus. Newly hatched larvae were sprayed with spore suspension (1x106 conidia spores/ml) of A. fumigates and A. flavus separately. One and 12 hrs. after in-oculation, larvae were sprayed with different concentrations of fungicide (Actamyl), sali-cylic acid, and henna and propolis powders, in isolation. After words, mortality and survival percentages were calculated and compared to those that occurred in untreated check (larvae were inoculated with A. fumigatus and A. fla-vus separately without any control treatment). The lowest mortality and highest survival per-centage were occurred in larvae treated with salicylic acid at 10% after 12 hrs. from inocu-lation with A. fumigatus. On the other hand, the lowest mortality and highest survival percent-ages occurred in larvae treated with the fungi-cide Actamyl at 6% and henna at 15% after 12 hrs. from inoculation with A. flavus.
اظهر المزيد [+] اقل [-]Evaluation of Different Control Methods on the Rust Flour Beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)
2021
Sara El-Deeb | Maha El-Ghannam | Pansea Azzam
The presented study aimed to evaluate the different control methods of the rusty flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). The experi-ments were conducted to evaluate the effi-ciency of a chemical pesticide (Mala-thion), biopesticide (Tracer 24% SC), plant oil (Lemongrass oil), plant extraction (Ac-etone extracts from Rosemary), powder (Diatomaceous earth) and modified At-mosphere (argon gas). Mortality percent-age increased with increase of exposure times at all tested concentrations. The tox-icity effect of different treatments against adults of T. castaneum at the LC50 after 7 days post-treatment at 30±1°C could be ar-ranged in descending order as follows: Malathion, Tracer 24% and lemongrass oil, while, acetone extracts from Rosemary and diatomaceous earth (DE) were the least effective. The LT50 values against the adult stage of T. castaneum were 19.99, 2.33 and 4.86 hr. for Argon 100, 80 and 60%, respectively. In order to avoid the disadvantages of using chemical insecti-cides such as malathion, it is recommended to use other more safe control methods for the environment as Tracer 24% or lemongrass oil or Argon gas.
اظهر المزيد [+] اقل [-]Effect of Clinoptilolite on Humoral Immunity and Biochemical Parameters in Calves Vaccinated with Foot and Mouth Disease Vaccine
2021
Nour Elhoda Tamim | Dawlat Salama | Hani Srour | Ehab Ibrahim
The foot and mouth disease (FMD) vaccine is used to control the FMD in cloven-hoofed animals including calves. The most important step in vaccine preparation is the selection of a suitable adjuvant which plays a main role in the vaccine’s potency. The present study is an attempt to use clinoptilolite instead of Montanide oil to enhance the efficiency of the FMD vaccine and reduce its production cost. Twelve calves were split into four groups. Three groups were vaccinated with FMD vaccine with different adjuvants i.e. 100% Montanide (ISA 206), 50% of Montanide with 1.0 μg/dose of clinoptilolite (ISA 206+CLINP), and by replacing the 100% of Montanide to 1μg/dose of clinoptilolite (CLINP). The fourth group was unvaccinated. Results showed that calves vaccinated with (ISA 206+CLINP) FMD vaccine expressed the highest and the longest periods of immune response until 38 weeks. While groups vaccinated with (CLINP) or (ISA 206) vaccine showed only protection up to 26 and 34 weeks respectively. Also, our results showed that clinoptilolite improved organ functions resulting from the stress of vaccines. Finally, this study recommended the use of clinoptilolite with Montanide oil as a potential adjuvant in the FMD vaccine to give high stimulation of the immune response.
اظهر المزيد [+] اقل [-]Capabilities of Hyperspectral Remote Sensing Data to Detect Soil Salinity
2021
Abdelrahman Medhat Saleh | Mohammed Abd-Elwahed | Yasser Metwally | Sayed Arafat
The objectives of the current study were to investigate the opportunity of estimating soil salinity from hyperspectral data and identifying the most informative spectral zones for estimation. Electrical conductivity (EC) measurements of ninety topsoil samples (0–30 cm) collected from Toshka, Egypt, were used as data set. Analytical spectral device was employed to collect the reflectance spectral signatures of soil samples. Both linear regression and HSD Tukey’s analyses displayed that the SWIR1 and SWIR2 zones are the most suitable for soil salinity prediction while, blue, green and NIR were the wickedest. Moreover, EC estimation was better in case of lower soil salinity (0-2 dS m-1) than higher levels (8-1). Partial-least-squares-regression (ΡLSR) was employed to establish soil salinity prediction model using the training set of soil samples (n=75). The PLSR model was set up using the most informative wave bands (SWIR1 and SWIR2). The result showed that PLSR linear model gave a precise prediction of soil salinity (R2 = 0.93). The results revealed that employing reflectance values in SWIR in the model variables increases the precision of soil EC prediction.
اظهر المزيد [+] اقل [-]Detoxifying Enzymatic Activity and Insecticide-Resistance Gene Expression in Field Populations of Pink Bollworm, (Pectinophora gossypiella (Saund.))
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.
اظهر المزيد [+] اقل [-]Turmeric Extracts as a Protective Natural Compound Against Hepatotoxicity Induced by Lead Nitrate in Male Albino Rat Model
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.
اظهر المزيد [+] اقل [-]Preparation and Thermal Stability of α-Tocopheryl acetate and Strawberry Anthocyanins Complexed with Starch and β-Cyclodextrin
2021
Eman Rashed | Hussein Ali | Mohamed Attia | Eslam Bendary | Khaled Ramadan
In the sake of enhancing the thermal stability of α-Tocopheryl acetate (α-TA) and Strawberry Anthocyanins (AN), their encapsulation with starch or β-Cyclodextrin were prepared and characterized by UV-Vis and IR spectra in addition to thermal analysis. Thermal stability was investigated by comparing the thermographs of each host and guest with that of the prepared complex. Both hosts provided extra thermal stability to both guests where α-TA is stabilized from 230 to 291oC by complexation with starch and to 285oC by encapsulation with β-CD. AN was also stabilized from 40.02oC to 75.57 and 79.46oC by complexation with starch and β-CD respectively.
اظهر المزيد [+] اقل [-]Identification and Reconsidering Phylogeny of Some Aphid Species, (Hemiptera: Aphididae), Based on Molecular DNA Markers Using ISSRs-PCR Technique
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.
اظهر المزيد [+] اقل [-]Soil hydrophysical properties as affected by kind of added polymer.
2020
Asmaa Musa | E Sallam | Usama Elbehairy | M Galal
Laboratory experiments were carried out to clarify the impact of different types of natural and synthetic polymers on some hydrophysical properties (soil hydraulic parameters) of a sandy soil. Adding 0.5% (w/w) of each treatment to soil significantly increased water retention at saturation, field capacity, total available water and readily available water. This treatment decreased the value of inflection point on water retention curve as result of enhancing water behavior in the soil. The obtained results revealed that soil water storage significantly increased from 0.271 in control treatment (without adding polymer) up to 0.414 in treatment [T10] (Acrylic acid + Xanthan) while, field capacity increased significantly from 0.078 in control up to 0.242 of the abovementioned treatment (T10). Regarding the effects of polymer application in total available water and readily available water, data revealed significant increases in the above mentioned parameters. Total available water increased from 0.044 in control treatment up to 0.153 in T10 and readily available water increased from 0.057in control treatment up to 0.185 in T10. Concerning values of inflection point on soil water retention curve, the obtained results revealed that, inflection point of control treatment (1000 mbar) decreased to 590 mbar, as a result of adding a mixture of polymer acrylic acid + xanthan (T10 ).Soil depletion rate decreased as due to polymer application by 25% up to 75% depending on type of polymer and wether it was added individually or in combination with another polymer. This effect led to significant differences among control treatment (control) and the other treatments. Generally, there were significant effects of all polymers on the concerned hydrophyical properties of the studied sandy soil, i.e. storage capacity of soil water, depletion rate of soil water, soil field capacity , soil available water, readily available water and inflection point on the soil water retention curve. Acrylic acid recorded the best results concerning soil water behavior if it was added individually to the sandy soil (Treatment 2) or in combination with Xanthan (Treatment 10) or with Lignosulphonate (Treatment 11).
اظهر المزيد [+] اقل [-]Effect of seaweed extract and biofertilizer on organic production of common bean seeds (Phaseolus vulgaris L.)
2020
M Amin | M Elshinawy | M Abdallah | H Abd El-Gawad
At the Experimental Farm, Agriculture Faculty, University of Ain Shams, Qaliobia Governorate, Egypt, in order to investigate the influence of biofertilizer ( Bio. ); Rhizobium ( R ), mycorrhiza ( MF ), R + MF and control, seaweed extract (SWE) concentration (zero, one, two and four gram per liter) and their interactions on vegetative growth, productivity and quality of seed common bean cv. Nebraska. Before planting, the seeds were soaked in MF (glomus sp.) and sown on the first of March 2016 and 2017 seasons respectively. The experimental plot area was seven m2 (four rows). The length of each row was 2.5 m and width of 0.7 m. The plant's distance was seven cm on one side, and an alley (one width m) was left as a border between the treatments. After two weeks of planting, young plant were inoculated with R phaseolus after the first irrigation. Plants were sprayed three times of SWE (30, 45 and 60 days) after sowing. A split plot design with four replicates was used; where the main plots are Bio treatments and the subplots are SWE treatments. The obtained results clearly indicated that different applied treatments increased measured growth characteristics (No. leaves/ plant, leaf area and total chlorophyll (SPDS)), the yield and components of yield (No. pods/plant, seed yield /plant and seed yield) and chemical constituents (total protein, carbohydrates, nitrogen and phosphorus) in seed after harvest. As well as, the best results were obtained by interactions between SWE (two and four gram per liter) and Bio. (R + MF) treatments in the two assigned seasons So adding combination between Bio. ( R + MF ) and SWE (two or four g) to improve vegetative growth, productivity and quality of common bean seed could be recommended under organic system ( conversion to organic agriculture ).
اظهر المزيد [+] اقل [-]