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LARVAL PARASITOIDS OF THE POTATO TUBER MOTH Phthorimaea operculella IN POTATO AND TOMATO FIELDS
2006
M.S.T Abbas | Salwa S.M. Abdel-Samad
Larval parasitoids of the potato tuber moth, Phthorimaea operculella Zell. were surveyed in potato and tomato fields in Menofyia Governorate in 2003. Three species were found to attack P. operculella larvae infesting potato plants; the endoparasitoids, Apanteles litae var. operculellae Nixon and Diadegma molliplum Hlmgrn. and the ectoparasitoid, Bracon instabilis Marshal. Meanwhile, only B.instabilis was found to attack the larvae infesting tomato leaves. Percentages of parasitism in potato fields averaged 10.8, 5.6 and2.6 % by B.instabilis, A.litae and D.molliplum, respectively. The total percentages of parasitism by the three species ranged from 11.0 to 28.6 % with an average of 19.1 % in potato field, while it ranged in tomato fields from 0.0 to 21.4 % with an average of 11.1 % by B. instabilis
Mostrar más [+] Menos [-]EFFECT OF VITAMIN ADDITIVE AND COLONY MAN-AGEMENT ON HONEY BEE PERFORMANCE
2006
A.M. Elbassiouny
The effect of both beekeeping processes (compressed bees Cb and traditional beekeeping Tb) and food diets (vitamins mixed with pollen grains, pollen grains only and plain sugar syrup) on the colony build up were studied during February – April, 2004, at the apiary belonging to Faculty of Agriculture, Ain Shams University. Feeding colonies with supplementary vitamins plus pollen grains resulted after four brood cycles significantly high daily rates of rearing brood (523 and 434 brood cells for Cb and Tb, respectively) and drawing combs (4.31 and 1.61 combs for Cb and Tb, respectively) compared to either unique pollen grains (432 and 338 brood cells and 3.2 and 1.19 combs for Cb and Tb, respectively) or plain sugar syrup (313 and 219 brood cells and 2.1 and 0.79 combs for Cb and Tb, respectively). On the other hand, the worker’s longevity recorded vice versa which were 21.2 26.2, 23.8 days for colonies fed on vitamins plus pollen grains, pollen grains and sugar syrup, respectively. The colonies which fed on vitamins plus pollen grains, pollen grains and plain sugar syrup, their workers were hoarded 236, 220 and 191 mg of sugar syrup / 3 days, respectively.
Mostrar más [+] Menos [-]STUDIES ON BACTERIAL POLLUTION IN LAKE MANZALA
2006
D.S. Ghaleb ; Abduljalil | A. Thabet Jamil | F.A Mansour | A Ismail | M.M . Zaky | M.I. Abou-Dobara
Lake Manzala in Egypt have shown great changes in water properties including pH (7.4 to 8.4), total suspended solids (19 to 350 mg/l), total dissolved salts (1578 to 33480 mg/l), dissolved oxygen (2.25 to 8.45 mg/l), ammonia (0.00 to 44.8 mg/l) and nitrate (0.00 to 8.96 mg/l). In addition there has been quite high bacterial density in water and fish of the lake, including total viable bacterial counts and indicator organisms such as total coliforms, faecal coliforms and some other organisms such as Aeromonas spp., Vibrio spp. and Staphylococcus spp. However, the magnitude number of bacteria in water and fish was found to vary sometimes considerably and sometimes slightly depending on the site of sampling. Our results herein showed that LakeManzala is highly contaminated.
Mostrar más [+] Menos [-]EFFECT OF TILLAGE TREATMENTS AND INTERCROPPING PATTERNS ON WATER USE EFFICIENCY AND YEILD COMPONENTS OF SOYBEAN AND MAIZE
2006
Sahar Sherif | Wafae Kh. Mohamed | Sahar T. Ibrahim | H.E . Osman | S.I El-Khatib
Two field experiments were performed at Sids Agriculture Farm Research Station, Bani Swif Governorate during 2003 and 2004 seasons, to study the suitability of different tillage treatments, i.e. chisel plough two and three passes at 10, 15 and 20cm depths and intercropping patterns of maize and soybean i.e. two ridges of maize : two ridges of soybean (2:2) and two ridges of maize : four ridges of soybean (2:4) on water consumption, growth characters, yield and quality of maize (cv. T.W.C. 310) intercropped with soybean (cv. Clark). The results indicated that using chisel plough 3 passes decreased the value of mean weight diameter (M.W.D) by 33.00%, 27.92% and 31.87% as compared when using chisel plough 2 passes for 10, 15 and 20cm depths respectively. On other hand, yield and quality of maize, as well as, yield and quality of soybean were significantly increased by using tillage with chisel plough 3 passes. Both yield of maize and soybean per feddan. in pure stand were always higher than those within any intercrop combination, these results were true in both seasons. The data also revealed that maize yield in (2:2) pattern and using chisel plough 3 passes at 15cm depth gave the highest yield whereas, the highest yield of soybean per feddan was obtained when soybean plants grown in (2:4) pattern with 3 passes of chisel plough at15cm depth. On other hand the highest values of water use efficiency (W.U.E) in the two seasons were recorded when (2:4) pattern was applied and using chisel plough 3 passes at15cm depth The highest values of land equivalent ratio (LER) in the two seasons were 1.54 and 1.53 respectively when (2:4 ) pattern was applied.
Mostrar más [+] Menos [-]ANTIOXIDATIVE PROPERTIES AND ANTIMICROBIAL ACTIVITY OF DIFFERENT AROMATIC EXTRACTS OF MELISSA officinalis L
2006
Shahinaz A.Helmy
The present study was carried out to maintain aromatic extracts of Melissa using different techniques (water distillation, steam distillation and extraction with acetone). The volatile components of these extracts were identified. Likewise, the antioxidative properties and antimicrobial activity of these extracts were determined. Data confirmed that the yield percent of acetone oleoresin extract was higher than both of water distillation and steam distillation extracts. Moreover, fractionation of volatile components using GC/MS technique showed the ability of acetone to extract more components than that of other techniques. In addition to being more effective in extracting higher amounts of sesquiterpene and phenols fractions. Odor threshold level confirmed that the concentration up to 1000 ppm from either water distillation or steam distillation extracts could be mixed with sunflower oil without affecting its odor, while acetone oleoresin extract could be used at concentration up to 800 ppm. Likewise, the different aromatic extracts of melissa exhibited antioxidative properties on sunflower oil. However, acetone oleoresin was markedly superior to that of water distillation as well as steam distillation extracts as antioxidant agents. This could probably attributable to the high content of some active components such as phenolic compounds in the acetone oleoresin extract. Also, antioxidant synergistic effect was observed for a mixture of 200 ppm tested extracts and BHT at 100 ppm. However, a mixture includes acetone oleoresin extract was the most effective as an antioxidant on sunflower oil. In conformity with antimicrobial activity, all tested extracts exhibited antimicrobial activities, however acetone oleoresin extract appeared the most potential antimicrobial spectra.
Mostrar más [+] Menos [-]PHYSICAL AND STRUCTURAL PROPERTIES OF THE PROMISING EGYPTIAN LONG STAPLE COTTON CROSS (GIZA 89 X GIZA 86)
2006
Nadia S. Abd El-Gawad
A promising cotton inbred line characterized by high yielding ability, earliness in maturity and better fiber quality was developed via pedigree selection from the subsequent segregating generations of a cross between the two long-staple cvs.; Giza 89 and Giza 86 by the Cotton Breeding Section of the Cotton Research Institute. The purpose of this investigation aimed at assessment of the superiority of the physical and fine structural properties of the promising line derived from the cross (Giza 89 x Giza 86) over its parents. The results indicated that: - The promising line surpassed its parents in upper half mean length, uniformity index, fiber strength, fiber elongation, micronaire value, maturity ratio, hair weight, dry fiber ribbon width, swollen fiber diameter, convolution number / cm., reversals number/ cm. and yarn strength. - There were highly significant positive correlations between upper half mean length, uniformity index, convolution number/cm., fiber bundle strength and yarn strength. - Highly significant negative correlations exhisted between dry fiber ribbon width, swollen fiber diameter, reversals number and bundle strength. The promising line is now under propagation for growing as a commercial cultivar and would replace both parents in their growing areas.
Mostrar más [+] Menos [-]SYNERGISTIC EFFECT OF VOLATILE OILS AND ANTIBIOTICS AGAINST SOME GRAM POSITIVE AND NEGATIVE PATHOGENIC BACTERIA
2006
M.F. Ghaly
Eight most currently used antibiotics were examined for their antibacterial properties against Gram-ve bacteria as Pseudomonas aeuroginosa, E. coli, Proteus vulgari and Gram+ve as Staphylococcus aureus, Streptococcus pneumonia. Nitrofurantoin was the most effective against the tested bacteria, the inhibition zones ranged between 16-20mm and the MIC between 65-85ug/ml followed by ampicillin (11-18mm), ciprofloxacin (9-12mm) and gentamicin (6-9mm). The erythromycin was the lowest effective against the tested bacteria. Also, seven volatile oils were applied by contact and fumigation methods to study their effect on the tested bacterial strains. The fumigation method gave the highest inhibitory effect more than contact method and the thyme oil gave maximum inhibitory action (inhibition zone 20-28mm) against all the tested bacteria, and the MIC ranged between 0.1-0.15mg/ml followed by marjoram oil (19-25mm) and the MIC between 0.1-0.2mg/ml, cinnamon oil (12-16mm) and the MIC between 0.2-0.3mg/ml. Anise and chamomile oils did not gave any response against all the tested bacteria. The combination between thyme and other tested oils gave a synergistic effect for inhibitory action against all the tested bacteria, if compared with thyme oil alone. The combination between thyme and marjoram oil gave the maximum inhibition zones (20-29mm), followed by thyme with cinnamon oil (20-27mm), thyme with geranium gave (18-27mm), thyme with peppermint (17-27mm), thyme with chamomile (16-27mm) and thyme with anise oil (15-26mm). The combination of thyme oil with different tested antibiotics gave the lowest inhibitory effect than combination between thyme and other volatile oils against all the tested bacteria. The protein and DNA content of treated bacteria with thyme oil were increased by 38.46-47.37% and 34.26-46.94% respectivily, if compared by non-treated bacteria
Mostrar más [+] Menos [-]EFFECT OF BROAD BEAN MOTTLE VIRUS INFECTION ON FABA BEAN NODULATION AND EFFICIENCY OF N2-FIXATION
2006
Hanaa H.A.Gomaa | M.M Hazaa | Kh.A El-Dougdoug | M.H Abdel-Ghaffar
Plant growth and root nodules of infected Faba bean plants with broad bean mottle virus were significantly reduced in plant height, leaf area, dry matter, number and size of nodules in comparison with healthy ones. As well Leghaemoglobin content and Nitrogenase activity were reduced in infected nodules at 45 days after BBMV inoculation. The amount of N2-fixed as expressed by acetylene reduction was reduced considerably by 38.8%. Nitrogen content as an indicator for the efficiency of N2-fixation was reduced in shoots, roots and root nodules of infected nodulated plants as compared with healthy nodulated ones. Differences between bacteroids in healthy and in BBMV infected cells were no longer apparent. These differences include: (i) a decrease in endocytotic and exocytotic vesiculation on the membrane envelope of the bacteriods and on plasma membrane of bacteroidal cells, (ii) a decrease in number of vesicles in the space between the bacteriod and the membrane envelope. The possible significance of these changes relative to the decreased efficiency of N2-fixation was discussed.
Mostrar más [+] Menos [-]FARMERS NEED OF AN EXTENSION PROGRAM TO RATIONALIZE IRRIGATION WATER AND MANAGE NEW IRRIGATION SYSTEMS IN “DARB AL-ARBE’EN” PROJECT, AL-WADY AL-GADID GOVERNORATE
2006
M.M Moustafa Muawad
The study aimed at identifying both knowledge and skill levels of farmers in regard of technical recommendations of rationalizing irrigation water use and its various management systems, determine the deficit in their knowledge and skills degree in that regard as a step to propose an extension program that hope to remedy this gap. The study was conducted in Al-Wady Al-Gadid governorate on beneficiaries of “Darb Al-Arbe’en” project, with a random sample of 160 represent about 25% of total beneficiaries (640). Data were collected through a personal interview questionnaire during (August-September) 2005, and the following statistics were used: frequencies, percentages, arithmetic mean, standard deviation, simple correlation coefficients, F test and multiple regression analysis (Stepwise).
Mostrar más [+] Menos [-]CROSS RESISTANCE OF DIPEL 2x RESISTANT STRAIN OF PINK BOLLWORM PECTINOPHORA GOSSYPIELLA (SAUND.) TO SOME CONVENTIONAL AND BIOINSECTICIDES
2006
El-Zemaity M.S. | A.E. Bayoumi | Mona F. Rofail | Hemat Z. Moustafa
A field strain of pink bollworm Pectinophora gossypiella (Saund.) collected from Sharquia Governorate, Egypt was exposed to the selection pressure of the for-mulation of Bacillus thuringiensis subsp. Kurstaki, Dipel 2x under laboratory condi-tions. Resistance ratio attained 16-fold based on the susceptible strain after 14 gen-erations of selection. Study the response of Dipel 2x resistant strain to some insecti-cides indicated that there is no cross resistance to the conventional insecticides, es-fenvalerate, chlorpyriphos and thiodicarb or the bioinsecticides Ecotech and Agerin. These data may be emphasizing the possibility of rotation the Dipel 2x with these insecticides in pest control program of pink bollworm to manage resistance to Bt products.
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