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Effect of gibberellic acid on the persistance of certain pesticides onion grape fruits
2010
Ahmed, N.S. | Zidan, Z.H. | El-Sayed, W. | Abdel-Hamid, R.M.
Recommended application was done by spray regime for two pesticides, namely diniconazole, fenitrothion and a plant growth regulator (gibberellic acid) and their mixtures. Their residues were determined after different successive treatments in and on grape fruits in two consecutive years. The initial deposits of the fungicide diniconazole when used alone were 0.49 and 0.50 ppm for 2006 and 2007, respectively. While the initial deposits of fenitrothion reached to 11.35 and 11.19 ppm for the same interval, respectively. Initial deposits of the plant growth regulator gibberellic acid were 30.52 and 30.42 ppm for the same period, respectively. After mixing the tested pesticides and the plant growth regulator, the initial deposits loss reached 38.77 and 42.0 % for diniconazole, 43.08 and 48.16 % for fenitrothion and 6.88 and 7.00 % for gibberellic acid for the same seasons, respectively. A significant degradation was recorded with the mixture of the two tested pesticides and plant growth regulator compared with that occurred when pesticide was used alone at' the two studied seasons.
Mostrar más [+] Menos [-]Formulation and evaluation the nematicidal activity of certain plant oils against citrus nematode Tylenculus semipenetrans
2010
El-Kady, A.M.A. | Ibrahim. H.S. | Farag, E.M.A. | El-Torkey, H.M.
Four plant oils namely Barka, Sesam, Garlic and Almond were prepared as emulsifiable con centrate (EC). Polyethylene glycol 600 dioleate (PEG 600 DO), Toximol R and Toximol H were used as emulsifiers while xylene and toluene used as solvents. Four formulations only passed successfully (F1, D2, C3 and E5) in the Physicochemical properties according to the standards of WHO. The results indicated that the successful prepared formulations showed different degrees of effectiveness against second stage juveniles of Tylenculus semipenetrans under laboratory conditions. Second stage juveniles seem as paralyze at 24 hrs, whereas this effect disappears completely after 72 hrs in case of Almond and Barka. On the other hand, the effect of Sesam and Garlic showed a slight effect at 24 hrs and increased gradually to give highly effectiveness after 72 hours. According to EC50 values at 72 hrs, Garlic was more effective than Sesam. The respective EC5o values were 0.6 and 2 mg/ml. These results emphasized the promising effect of certain plant oil formulations including Garlic and Sesam oil against pathogenic nematode, and that such formulation might be used for nematode control in small areas, as gardens and plant nursery.
Mostrar más [+] Menos [-]Effect of neem and willow aqueous extracts on fusarium wilt disease in tomato seedlins 1-induction of antioxidant defensive enzymes
2011
Farag, H.R.M. | Abdou, Z.A. | Salama, D.A. | Ibrahim, M.A.R.
. The effects of neem (Azadirachta indica) and willow (Salix babylonica) aqueous extracts on fusarium wilt disease in tomato seedlings were investigated. Four weeks old tomato seedlings were treated with 10% of either neem and willow aqueous extracts and then infected with Fusarium oxysporum after 4 days of treatment. The results showed that the percentage of disease incidence was increased in non treated tomato seedlings in time dependent manner and reached the maximum level (65%) after 6 weeks of infection. Treatments of tomato plants with neem and willow aqueous extracts reduced the percentage of disease incidence to the level of 25.5% and 27.8% after 6 weeks of infection respectively. The results show that infection of tomato seedling with Fusarium oxysporum led to many morphological and biochemical changes including, reducing the growth of tomato shoot and root, increasing the level of lipid peroxidation and marked increase in the activities of antioxidant defensive enzyme I.e. POX, CAT, and SOD. Treatment with neem and willow aqueous extracts significantly exhibited a growth promotion of tomato shoot and root in infected or non infected seedling. Moreover, application of neem and willow aqueous extracts with fusarium, significantly reduce the level of lipid peroxidation and induce high activities of antioxidant defensive enzymes after 3 and 7 days of infection. Electrophoretic pattern of POX demonstrated that Fusarium oxysporum caused up regulation of several POX isoenzymes. It could be concluded that neem and willow aqueous extracts reduced the disease incidence of fusarium wilt in tomato seedlings by increasing the activities of antioxidant defensive enzymes and decreasing the level of lipid peroxidation.
Mostrar más [+] Menos [-]Analytic study of short fiber content in Egyptian cotton
2011
Ebado, E.A. | Hassan, R.M.
The experiment was conducted through two successive seasons of 2008 and 2009 at El Bosaily farm, EI-Behira governorate at the North Coastal of the Nile Delta, in Egypt. This work aimed to study the effect of three green-house covers (polyethylene sheet, white and black net) and three irrigation levels 180%, 100% and 120% of the potential evapotranspiration estimated according to class A pan equation (ET,)], applied by drip irrigation system, on plant growth and crop yield of Cucumber (Cucumis sativus L.. cv. Reda F1). The experimental design was split- plot with three replicates. The results showed that white net green-house cover optimized growth and yield of cucumber plant. White net cover treatment recorded the highest vegetative growth (plant height, number of leaves, total leaves area, total fresh and dry weights), and significantly increased total yield. The highest vegetative growth was obtained by 100% ETo compared to 80 and 120% ETo treatments. The interaction among water treatment and green-house cover indicated the highest vegetative growth and crop yield were obtained under white net cover with 100% ET,.
Mostrar más [+] Menos [-]Zinc and manganese sorption behavior by natural zeolite and bentonite
2011
Iskander, A.L. | Khald, E.M. | Sheta, A.S.
Understanding the sorption process in natural zeolite and bentonite is necessary for effective utilization of these minerals as nutrient adsorbents and on the other side for controlling release of plant nutrients. This research was undertaken to characterize the ability of natural zeolite and bentonite minerals to adsorb and release zinc and manganese. The potentials for sorption of these ions were evaluated by applying the Langmuir and Freundlich equations. The results showed that Langmuir constant (maximum adsorption (b mmol kg-1)) of both Zn and Mn were for bentonite zeolite While the [binding strength values (k in L.mmol1 for zeolite bentonite Zn in case of zeolite showed the lowest desorbed percentage particularly at high levels of sorbed Zn. Only, 74.7 % is readily extractable by DTPA after three successive extractions leaving, 25.3 % Zn retained by the mineral. In case of bentonite, 82.26 % of sorbed Zn is readily extractable by DTPA after three successive extractions leaving, 17.74 % Zn retained by the mineral. In case of Mn, 84.63% of Mn sorbed by zeolite is readily extractable by DTPA after three successive extractions leaving, 15.37% Mn retained by the mineral. In case of bentonite, 89.79 % of adsorbed Mn is readily extractable by DTPA after three successive extractions leaving, 10.21 % Mn retained by the mineral. This finding may reflect clearly the possibility of using natural zeolite and bentonite as a slow release fertilizer for Zn and Mn and on the other hand preventing soil pollution with heavy metals.
Mostrar más [+] Menos [-]Study of genetic relationship between some olive varieties in gellin gene bank
2011
Moustaf, N. | Hamed, F. | Lawand, S.
Olive tree (Olea europaea L.) is one of the most important fruit trees, there is a lot of varieties with the possibility of mislabeling, homogenouses and synonyms, which makes major troubles when having plant material for propagation and breeding programs. In this search, 12 olive varieties (Maw! Istanbul!, Khilkhali Khishen, Dan, Mniekri, Adkam, Doaibli, Mot, Khilkhali Saghir, Karamani Modabal, Mawi abo Shokeh, Sourani, and Abo Shokeh), cultivated in ACSAD Gene bank in Gellin, were characterized by ISSR molecular markers to determine the relationship between these varieties. Depending on quantitive traits the results indicated that these varieties are so close to each other's, ranged from 60% and 85%. It was noticed that Mneikri was apart from the other varieties in its traits, (polymorphic rate was 92.94%).
Mostrar más [+] Menos [-]Effect of harvesting dates on the yield and quality of some flax genotypes
2010
El-Kady, E. | Salama, A.S. | Abd-El-Fattah, A.A.
Two field experiments were conducted during the two successive seasons 2007/2008 and 2008/2009 at Sakha Agric. Res. Station, Kafr ElSheikh Governorate to study the effect of four harvesting dates i.e. 135, 145, 155 and 165 days after sowing on yield and its quality of six flax genotypes namely, Sakhal, Sakha 2, Sakha 3 and Giza 9 varieties and two new promising strains (strain 16 and strain 22). This study was laid out in a split-plot design, with four replications, the main plots were allocated to the six flax genotypes, whereas, the sub-plots contained the harvesting dates. The obtained results could be summarized as follow: Sakha 3 and Giza 9 varieties gave the highest means for technical length, fiber yield/plant as well as per fed., fiber length, fiber percentage, fiber strength, fiber fineness, germination % and crude protein %, whereas strain 22 (yellow seed) surpassed the other flax genotypes which produced the highest values for No. of seeds/plants, seed yield/fed., oil content and oil yield/fed. The harvest date of 155 days after sowing showed significant increases in stem diameter, straw yield/plant as well as per fed. fiber yield and its quality and crude protein % compared to the other three dates (135, 145 and 165 days after sowing). However, delayed harvesting date to 165 days after sowing recorded significant increase in technical length, upper branching zone length, seed yield and its related characters, germination %, seedling vigour, seed index, volume of 1000 seed,'oil content and oil yield/fed. The interactions among the studied factors had significant effects on straw yield/fed., No. of capsules/plants, fiber strength and germination % in the first season of study, while the characters of the upper branching zone length, seed yield/fed., oil yield/fed., fiber length and oil content in both seasons.
Mostrar más [+] Menos [-]Effect of treatment on the nutritive value and residues of some synthetic pesticides in fresh bolti fish
2010
Ahmed, N.S. | El-Saad, El.O.
Fresh Bolti -fish (Tilpia nilotica) collected randomly from 9 different markets in Ismailia Governorate for evaluation the effect of grilled fish by the method used in grillrooms and houses on the concentration of pesticide residues found and the nutritive value. Results revealed that decrease in the estimated parameters i.e. moisture, crude protein, fat and ash by grilling, this decrease were 6.07, 2.63, 4.07 and 1.56%, respectively. On the contrary, carbohydrates behaved another behavior that there was an obvious increase ranged from 1.98% to 2.92%. Fresh and grilled fish were analyzed to detect 12 organochlorine (OC) and 7 synthetic pyrethroid (SP) pesticides with a mean level on a lipid basis. Gas Liquid Chromatography equipped with Electron Capture Detector GC-ECD was used to detect the contamination in the samples. The results showed that p,p'-DDE isomer was dominated over the other isomers in all analyzed fish samples, followed by q-isomer of hexachlorocyclohexane. The concentrations of OC residues were higher than SP pesticides in all fish muscles. Also, the fresh fish muscle recorded higher concentrations of the evaluated pesticides than the grilled one.
Mostrar más [+] Menos [-]Taxonomic study of the genus Zygophyllum in Egypt. 1.- morphological features
2003
Ahmed, K.A. | Mohamed, A.H.Azhar Univ., Cairo (Egypt). Faculty of Science (Girls))
Effect of some constituents of citrus essential oil against postharvest pathogenic fungi of citrus fruits
2002
El-Mohamedy, R.S.R. | Abdel-Kareem, F. | Abd-Alla, M.A. (National Research Center, Cairo (Egypt). Plant Pathology Dept.)