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POPULATION FLUCTUATIONS OF IMMATURE STAGES OF THE CITRUS FLOWER MOTH, PRAYS CITRI MILL. (LEP.: HYPONOMEUTIDAE) ON LIME TREES
2018
A.F., Badr | A.M. Hekal | L.A. Youssef
Mill. on lime flower buds showed six annual population peaks of 13.3, 1.2, 1.8, 6.2, 2.8 and 3.4 in mid-May, mid-Oct., mid-Nov., mid-Dec., midFeb. and mid-Mar., respectively during 2015/2016 season. Five peaks of 13.5, 14.5, 1.8, 5.8 and 5.0 immature stages were observed on flowers in midApr., mid-June, mid-Oct., mid-Dec. and mid-Mar., respectively. On newly formed fruits, five peaks of 7.3, 0.4, 2.2, 1.8 and 2.4 immature stages were also recorded in the middle of June, Oct., Dec., Feb. and Mar., respectively. The general mean was the highest (11.3 immature stages) in June, while it was the lowest (0.0 immature stage) in Sep. The highest population density of P. citri was recorded in spring, followed by summer then winter and autumn. The seasonal mean was 4.1 immature stages in 2015/2016 season. The same trend could be applied during 2016/2017 season. Six peaks of 12.8, 2.5, 4.0, 5.8, 3.3 and 4.6 immature stages were estimated on lime flower buds in mid-May, mid-Oct., mid-Nov., mid-Dec., mid-Feb. and mid-Mar., respectively. Mean numbers of P. citri immature stages on flowers also exhibited six peaks of 14.5, 2.8, 5.3, 7.2, 4.3 and 5.6 in mid-Apr., mid-Oct., mid-Nov., midDec., mid-Feb. and mid-Mar., respectively. Six peaks of 5.8, 1.0, 1.8, 3.0, 1.5 and 2.4 immature stages were also found on newly formed fruits in the middle of May, Oct., Nov., Dec., Feb. and Mar., respectively. The highest general mean was 10.8 immature stages in May, while the lowest was 0.0 immature stage in Sep. The highest population density of P. citri occurred in spring, followed by summer then winter and autumn. The seasonal mean was 4.6 immature stages in the second season.
Afficher plus [+] Moins [-]EVALUATION OF WHEAT FLOUR BLENDED WITH DIFFERENT RATIOS OF MORINGA OLEIFERA LEAVES AND SEEDS
2018
A.R., Khalaf | M.H., El-kalyoubi | M.F. Khallaf | A.S. Hussein | I.F. Helmy
Chemical composition, minerals content, amino acids, fiber fractions, fatty acids profile, total phenols, total flavonoids and antioxidant activity were determined in wheat flour (WF) 72%, moringa leaves powder (MLP), defatted moringa seeds powder (DMSP) and moringa seeds (MS). Pasting profile and rheological properties of blends supplemented with MLP at levels of 3, 6, 9 and 12% or DMSP at levels of 5, 10, 15 and 20% were also studied. The highest moisture and carbohydrate contents were found in WF (12.60 and 85.05%), respectively. MLP had higher ash and fiber contents (8.87 and 7.91%), respectively, while, protein and fat contents were higher in DMSP and in MS. Mineral content (Ca, K, Mg, P, Na and Fe) in MLP was the highest, while DMSP was higher in Zn content than that of other samples. Fiber fractions of WF were lower than that of both MLP and DMSP. Total essential amino acids of DMSP was higher (19.25%) than that of MLP and WF (12.45 and 4.16%), respectively. Oleic acid was the predominant fatty acid (66.85%) in moringa seeds oil. MLP had the highest value of total phenolic, total flavonoid and antioxidant activity (11.97, 8.02 and 15.87 mg/g), respectively. Color measurements showed that all of MLP, DMSP and WF blends decreased in L*, a*,however, they increased in b*, saturation, hue and ∆E values. Supplementation with MLP and DMSP at all levels decreased the peak viscosity, trough, breakdown, final and setback viscosities. While, it increased water absorption, dough development time, mixing tolerance index and dough weakening. On contrary, arrival time and dough stability were decreased. Also, MLP and DMSP decreased the extensibility, resistance to extension, maximum resistance to extension energy of dough and the proportional number.
Afficher plus [+] Moins [-]ISOLATION, IDENTIFICATION AND BIOCONTROL OF SALMONELLA TYPHIMURIUM IN KARIESH CHEESE BY BACTEIOPHAGE
2018
Atef Fayed | Ragia O. Mohamed | M.A. Hassan | A.E. Fayed
The study aims to assess the possibility of biological control on one of the most serious pathogenic microbes that found to infect Kariesh cheese, namely Salmonella typhimurium. To achieve this object, firstly a total of 20 Kariesh cheese samples were collected randomly from various markets located at Cairo and exposed to microbiological isolation and identification of S. typhimurium. The obtained results revealed that, S. typhimurium was detected in 30% of surveyed market Kariesh cheese according to the strain identified by polymerase chain reaction (PCR) technique. Secondary, five sewage water samples were obtained from Fac. of Agric., Ain Shams Univ., and Shoubra EL-Kheima station of drinking and sewage water for specific bacteriophage isolation and morphology particles of Salmonella bacteriophage was examined by transmission electron microscope. Third, pasteurized skimmed buffalo’s milk was converted into experimental Kariesh cheese at 40oC by milk inoculation with 2% of freshly activated yoghurt bacterial starter culture and then milk was divided into 5 equal portions. The 1st portion considered as control. The 2nd, 3rd, 4th and 5th portions were contaminated with equal level (1%) of S. typhimurium suspension containing 105 colony forming units (CFU)/mL, previously isolated from foregoing surveyed Kariesh cheese samples, followed by adding phage suspension, from which isolated from sewage water, containing 108 plaque forming units (PFU)/mL at the levels of nil, 1, 2 and 3% respectively. All portions were separately incubated at the same temperature up to curdling. The curds were cut and individually filled into stainless steel moulds lined with cheese cloth and consolidated by a slight pressure for 24 h. The blocks of curd were then cut, dry salted using 2% NaCl (w/w) and packaged into plastic containers. Experimentally, there were proportional reductions in lactic acid bacteria (LAB) population as the level of phage spiked into cheese milk increased, as which the reduction rate of LAB count during cold storage period (CSP) prolonging was however declined. In terms of health safety, although the number of pathogen microbe added was gradually reduced due to the acid developed by prolonging the Cold Storage Period in the absence of phage, but it stilled present until the end of experimental period. While, the pathogen was completely eliminated within 7 days of cheese age when the phage suspension (108 PFU/mL) has been spiked at the level of 1% at least. The contamination of experimental Kariesh cheese with S. typhimurium led to weaken the ability of cheese curd to drain whey as explained from the dry matter (DM) content which decreased due to the presence of pathogen and increased by the pathogen elimination with bacteriophage, which resulted also to increase the protein /DM content. The ash content reduced by both reasons, namely the contamination with S. typhimurium and/or the spiking level of phage suspension. The presence of S. typhimurium slowed the LAB population and acid production by them. Finally, as a conclusion, the spiking of Kariesh cheese milk with 1% Salmonella typhimurium phage suspension (108 PFU/mL) is quite enough to eliminate this microorganism when it present at the level of 1% suspension containing 105 CFU /mL.
Afficher plus [+] Moins [-]IMPACTS OF CYANOBACTERIA AND BRADYRHIZOBIUM INOCULATION ON LUPINE PLANTS UNDER DIFFERENT NITROGEN RATES IN SANDY SOIL
2018
fekry ghazal | Hala A.M. El-Sayed
A field experiment was conducted in sandy soil at Ismailia Agricultural Research Station, (Ismailia Governorate, Egypt, in two successive winter seasons of 2015/2016 and 2016/2017. The experiment aimed to study the response of lupine plants (Lupinus albus L.) variety Giza 2 to cyanobacteria applied with different methods under different nitrogen fertilizer rates and inoculated with rhizobia. Results revealed that application of cyanobacteria generally increased the mean values of nodules number, dry weight of nodules and shoot dry weight of lupine plants, nitrogen uptake, biological activity of the soil rhizosphere lupine plants, yield, yield components and seed protein content as compared to those recorded by the control treatment without cyanobacteria. Increasing nitrogen rates decreased the mean values of both nodules number and dry weight of nodules. On the contrary, increasing nitrogen rate up to 100% of the recommended one increased all the other tested parameters. The highest values of these parameters were recorded when cyanobacteria were applied as dry + soaking combined with 75 % N rate expect for those of number and nodules the dry weight of nodules that gave their highest values when the lupine plants received the treatment of dry + soaking combined with 50 % N rate. In conclusion, the use of cyanobacteria along with rhizobia as renewable nitrogen source for lupine production can save 25% N from that required for lupine.
Afficher plus [+] Moins [-]IN VITRO PROPAGATION OF KORONAKI AND CORATINA OLIVE CVS.
2018
Rehab N. Mostofa | M.A., Abu Rawash | H.F. Elwakeel | Vergini F. Noaman
Experiments carried out through 2016 revealed that a proper protocol for the in vitro propagation of Koronaki and Coratina olive cvs. as follows : Sterilization of stem node explants was carried out successfuly with copper sulphate at 50mg/l for Koronaki cv. And Ampicillin at 150mg/l for Coratina cv. both cultured on Olive medium.Multiplication on MS medium enriched with BAP at 1.5mg/l for both cvs. Rooting of Koronaki on half sterngth OM medium enriched with IBA at 0.5mg/l and Coratina on half sterngth MS medium enriched with NAA at 0.1mg/l. Acclimization of Koronaki plantlets derived from half strength OM rooting medium and acclimatized on peat : sand (1:1) and Coratina plantlets derived from MS rooting medium and acclimatized on peat :sand : vermiculite (1:1:1).
Afficher plus [+] Moins [-]VARIETAL VARIATIONS OF SESAME IN NITROGEN UTILIZATION EFFICACY
2018
Noha S. El-Khouly | H.S. Saudy | W.R. Abd El-Momen
From an eco–economic perspective, the efficient use of nitrogen is becoming incrementally worthwhile in crop management. Therefore, growth, yield and seed yield response index of three sesame varieties (Shandwel–1, Giza–32 and Sohag–1) as affected by four N rates (0, 72, 108 and 144 kg N ha−1) were investigated during two seasons of 2013 and 2014. The study illustrated that Sohag–1 was the superior variety for achieving SPAD value and seed yield ha−1. Sesame plants can be fertilized with N at a rate of 108 kg ha−1 being recorded higher seed yield ha−1. Integration between proper variety as a genetic factor with the appropriate N rate applied as an environmental one, i.e. Sohag–1 x 108 kg N ha−1 (or Sohag–1 x 144 kg N ha−1) considered a marked practice for gaining high sesame seed yield as an economic product. Being Sohag–1 exhibited less reduction in yield under low N rate and highly response with high N applied it belongs to ER group.
Afficher plus [+] Moins [-]REMOVAL OF ALIZARIN RED S FROM AQUEOUS SOLUTION USING SODIUM BENTONITE
2018
Eman A. El-Menofy | Omnia I. Ali | A.H.T. Kandil
In this work, sodium bentonite (Bn) was used for removal of alizarin red S (ARS) from aqueous solution using batch technique. Fourier transform infrared spectroscopy and X-ray diffraction were used to characterize sodium bentonite. Different parameters that would affect ARS dye removal such as initial pH, contact time, initial ARS dye concentration, bentonite dose, and temperature were explored. The realized data from kinetic studies demonstrated the high fitness of pseudosecond-order kinetic model for better interpretation of the experimental data. The adsorption isotherms studies showed that Freundlich isotherm had a high correlation coefficient among the studied isotherm models. Thermodynamic studies proposed that ARS adsorption onto Bn was spontaneous in nature at the lower temperatures and exothermic.
Afficher plus [+] Moins [-]SUSCEPTIBILITY OF DESERT LOCUST, SCHISTOCERCA GREGARIA (ORTHOPTERA: ACRIDIDAE) TO BACILLUS CEREUS ISOLATED FROM EGYPT
2018
M. Reda | T. Mashtoly | M. El-Zemaity | A. Abolmaaty | G. Abdelatef | A. Marzouk
Examination was done at preliminary bracketing bioassay on one old 4th nymphal instar of desert locust. Results showed that two isolates, namely NDL1 and NDL2 were having highly potentiality as entomopathogenic bioagents. Thirty isolates were isolated from dead/ infected nymphs of desert locust occurred in raring cages at Department of Locust and Grasshoppers Research, Plant Protection Research Institute, Agricultural Research Center, Dokki, Giza, Egypt. Molecular identification of isolated bacteria was done using universal primers of 16s rRNA, followed by DNA sequencing. Nucleotides were blasted at (https://www.ncbi. nlm.nih.gov /genbank/) to recognize that NDL1 and NDL2 isolates were two different isolates of Bacillus cereus with a high similarity (100%). Susceptibility of 4th nymphal instar of Schistocerca gregaria (Forskal) to the isolated B. cereus was determined using two bioassay procedures, Leaf-dip and per os. The insecticidal activity of both isolates against locust nymph in leaf dipping showed that NDL2 was more efficient than NDL1. However, the opposite trend was observed in using per os. Both Isolates have the potential to be a successful biocidal agent to control desert locust.
Afficher plus [+] Moins [-]CONTROL OF ANGULAR BACTERIAL LEAF SPOT DISEASE OF WATERMELON USING ADVANCED COPPER COMPOSITES
2018
M. Ebrahim | Wafaa Abd El-Sayed | N. Abd El-Ghafar | M. Paret | M. Young | S. Santra | J. Jones
Angular leaf spot, caused by P. syringae, is one of the most important bacterial disease of watermelon. For disease management, growers rely on copper bactericides, which are effective after the first two weeks of transplanting, while they couldn’t be applied before that due to the high phytotoxicity they may cause to the plant. This study was undertaken to evaluate the antibacterial activity of three new copper composites, core-shell copper (CS-Cu), multivalent copper (MV-Cu), and fixed quaternary ammonium copper (FQ-Cu), as potential treatments to control the disease before the emergence of the first true leaf where copper is not available, and to identify the possibility of applying the newly designed copper composites during that period to significantly reduce secondary dispersal of disease inoculum. In vitro, 50 μg/ml of metallic copper from MV-Cu and FQ-Cu significantly reduced the P. syringae populations after 2hrs of exposure compared to the untreated control (P= 0.05) and were more effective than using the Kocide® 3000. Greenhouse studies demonstrated that MV-Cu and FQ-Cu significantly reduced the disease incidence compared to both Mankozeb+ Kocide® 3000 and untreated control when using the seed inoculation method. In contrast, none of the nano-composites significantly reduced disease incidence when using the spray inoculation method. MV-Cu and FQ-Cu managed to significantly reduce seedling to seedling disease transmission under greenhouse conditions (P = 0.05). This study highlights that copper composites have the potential to manage P. syringae in the first two weeks of transplanting and reducing the contamination rate from infected to healthy transplants
Afficher plus [+] Moins [-]AN EXPERT SYSTEM FOR SELECTING THE TECHNICAL SPECIFICATIONS OF DRIP IRRIGATION CONTROL UNIT
2018
Samar Ragab | A. El-Gindy | Y. Arafa | Maybelle Gaballah
The good design of irrigation system is one of the main steps of extent the life of the irrigation system, as well as increase the cultivated crop productivity by choosing the proper components of irrigation system control head unit ( such as pump, motor, filters, main line pipe, fertilization device, and the different control unit attachements). Different types of control unit components are used according to the system conditions for irrigation of agricultural areas. It is very difficult to find an expert at desired time and desired place for choosing correct control unit which are varied in different types and models. In this study, this problem was to be tried to solve by designing of an expert system for choosing proper components of control unit in irrigation network. A rule-based program named TSDI-ES (Technical Specification of Drip Irrigation-Expert System) was coded and compiled using Microsoft visual basic 2013 language. Generally, the expert system database obtained from commonly used all components of control unit in irrigation network in Egypt. selection of all components of control head unit in irrigation network were determined by taking into consideration the following parameters: water resource, irrigation methods, irrigation area, crop pattern, climate, soil properties, and well characteristics. Results of the investigation indicated that it is possible to use the TSDI-ES rule-based program for choosing all proper components of control head unit in drip irrigation network such as pump, filtration unit, fertilizers devices, and flow, pressure measuerement and control devices.
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