Уточнить поиск
Результаты 31-40 из 57
BIOLOGICAL CONTROL OF MELOIDOGYNE JAVANICA AND RHIZOCTONIA SOLANI ON SOYBEAN BY FORMULATION OF BACILLUS THURINGIENSIS AND TRICHODERMA HARZIANUM Полный текст
2006
M.E Mahdy | E.Z Khalifa | Rania Z. El-Shennawy
Preparationof either Bacillus thuringiensis or Trichoderma harzianum were used as seed coating or soil application for management of root-knot and root rot disease complex caused by the root-knot nematode, Meloidogyne javanica and the fungus Rhizoctonia solani on soybean plants. Number of galls, root galling, egg masses and disease severity were reduced sharply on plants treated with both biocontrol agents, either as seed or soil application compared with non-treated plants. Soil application with both biocontrol agents was the best method in reducing nematode and fungus disease severity. Plant growth parameters i.e. fresh shoot and root weight, dry weight and number of pods and bacterial nodules were markedly increased with all treatments of biocontrol agent either with seed or soil treatment compared to plants grown in infested soil with either pathogens alone or combined. Results show that plant survival was more affected when R. solani was alone or combined with M. javanica. Seed coating was considered the effective method in increasing survival plants. The biochemical analysis of treated plants with both biocontrol agents were affected compared to non-treated plants grown in pathogen infested soil. The biochemical parameters i.e. chlorophyll A and B, carotein, phenols and amino acids were enhanced in bioagent treated plants compared to non-treated plants
Показать больше [+] Меньше [-]CERTAIN BIOLOGICAL ASPECTS, THRESHOLD OF DEVELOPMENT AND THERMAL UNITS FOR HYMENIA recurvalis (FAB.), (LEPIDOPTERA: PYRALLIDAE) Полный текст
2006
Seham S.M. El-Gendi | F.F.M . Mostafa | F.A.E . Aly | S.H.A Hussein
Biological studies on the Hawaiian beet webworm, Hymenia recurvalis were carried out under laboratory conditions of 18.6 ± 2°C and 70 ± 5% R. H. The incubation period ranged between 5 and 7 days with a mean of 6.0 ± 0.3 days. The mean durations of larval, prepupal and pupal stages were 26.29 ± 0.3, 5.04 ± 0.08 and 16.86 ± 0.18 days, respectively. Mean adult longevities were 28.42 ± 1.80 and 26.08 ± 1.83 days, ranging between 19-41 and 15-37 days for female and male, respectively. The sex ratio was about 1 : 1.3 (♀ : ♂ ). Accumulative thermal units needed for certain biological features of H. recuurvalis were calculated and the estimated thermal thresholds were 10.97, 12.14, 10.49 and 13.55°C for egg, larval, pre – pupal and pupal stages, respectively. The corresponding values for the thermal units needed for development of these stages were 51.49, 168.47, 47.88 and 102.59 day degree at 25°C for the respective stages.
Показать больше [+] Меньше [-]ANTIOXIDATIVE PROPERTIES AND ANTIMICROBIAL ACTIVITY OF DIFFERENT AROMATIC EXTRACTS OF MELISSA officinalis L Полный текст
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.
Показать больше [+] Меньше [-]SYNERGISTIC EFFECT OF VOLATILE OILS AND ANTIBIOTICS AGAINST SOME GRAM POSITIVE AND NEGATIVE PATHOGENIC BACTERIA Полный текст
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
Показать больше [+] Меньше [-]EFFECT OF BROAD BEAN MOTTLE VIRUS INFECTION ON FABA BEAN NODULATION AND EFFICIENCY OF N2-FIXATION Полный текст
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.
Показать больше [+] Меньше [-]MITE FAUNA ASSOCIATED WITH SOME DOMESTIC AND WILD AGRICULTURAL ANIMALS AND THEIR HABITAT IN EGYPT Полный текст
2006
A.E.A Mahgoob | M. E . Tharwat | Samia . O. Kilany | T.S . Hafez
Random samples were collected from Giza Qualubyia and Minufyia Governorates during summer, autumn and winter 2001. The collected samples were litter, poultry food and feather from chickens, ducks, pekeeny ducks, geese, rabbits (as a domestic animals) and quails, rozella birds, zebra birds and kockteel birds (as a wild animals which were in captivity). Mites belonging to twenty-seven families of four suborders; viz., Gamasida, Actinedida, Acaridida and Oribatida plus the hypopal stage of family Acaridae, were collected. Out of 27 families, 24, 14 and 11 were found in Qaliobia, Giza and Minufyia Governorates, respectively. However, number of mites, percentage of occurrence and dominance differentiated families in and between localities. Number of mites during autumn season was the highest representing 21 families followed by summer then winter. Hypopal stage represented about 20% of mite population in autumn season while no hypopal stage in summer but nil in winter. Litter harbored mites of all 27 families and hypopal stage which was not found in feather and food. The percentage of mites and hypopal stage was 89.39% in litter, followed by feather (9.51%) then food (1.1%). Only 6 and 5 families were found in food and feather respectively. Feather of Pekeeny ducks harbored 49.5% of mites while chicken’s feather harbored 42.6%. The percentage of mites in leftover food was 89% while it was 11% in food before feeding. The most common mite families in this study were Acaridae, Glycyphagidae Pyroglyphidae, Cheyletidae, Ascidae and Dermanyssidae. Declaration of the role of the animals under investigation and their habitat as a source of stored product mites also the dominance of occurrence of the recorded mite families were discussed in details
Показать больше [+] Меньше [-]POTENTIAL FORAGE YIELD OF CANARY GRASS (PHALARIS CANARIENSIS L.) IN RELATION TO BIOFERTIL-IZER AND SOME MICRONUTRIENTS UNDER RECLAIMED SOIL CONDITIONS Полный текст
2006
A.A. El-Houssini
This investigation has been performed in Mariout Research Station, Desert Research Center (D.R.C.) throughout two successive growing seasons of 2002 / 2003 and 2003 / 2004. Canary grass plants were raised under 9 treatments which were the combinations of 3 biofertilizer sources i.e. Azotobacter, Azospirillum and uninoculated control and 3 micronutrients i.e. 2% FeSo4, 1% MnSO4 and control. The treatments were arranged in split-plot design with three replications. The important results obtained can be summarized as follows: 1- Maximum values of all growth parameters tested of canary grass plants were obtained when seeds were inoculated with Azotobacter compared to inoculation with Azospirillum or uninoculated control. Fresh and dry forage yields followed the same trend of growth parameters in their response to the different biofertilizer resources. 2- All growth and forage yield traits of canary grass plants were increased when the plants were sprayed with 2% FeSo4 compared to spraying with 1% MnSo4 or control treatment.
Показать больше [+] Меньше [-]MONITORING OF PESTICIDE RESIDUES IN SOME ENVIRONMENTAL ELEMENTS AT MENOFIA GOVERNORATE, EGYPT Полный текст
2006
El-Zemaity, M.S. | M.I. Abd El-Megeed | A.E. Bayoumi | M.A. Hamaad
The pesticide residues in drinking water, irrigation water, sediment and soil sam-ples collected from three villages, i.e. Samadon, Ashmon and El-Ramla, located at Menofia Governorate, Egypt were monitored during the period of Septemper 2002 to February 2003. The obtained results showed that the detected pesticide residues were varied in their types and structures in the investigated villages during period of study. It is clear that residues of organochlorine insecticide and the herbicide, atra-zine, were the most frequently detected in both of drinking and irrigation water sam-ples. According to the detected amounts and numbers of pesticide residues in all the collected samples, the soil samples contained higher pesticide residues (average of 0.07 ppm) sediment (average of 0.05 ppm) irrigation water (average of 0.04 ppm) drinking water (0.01-0.02 ppm). Comparing between the selected sites, Sa-madon was the highest site contained pesticide residues more than Ashmon and El-Ramla.
Показать больше [+] Меньше [-]IN VITRO PROPAGATION OF SOMATIC EMBRYOGENESIS-DERIVED PLANTLETS OF CITRUS Полный текст
2006
El-Sawy, A. A. | A. Reda | A. Gomaa | Nansy Danial
Nodal stem segments of in vitro growing somatic embyogenesis and seedling-derived plantlets of sweet orange, C. sinensis (L.) of (Washington navel, shamouti and blood orange cvs.); grapefruit, C. paradisi (L.); Local mandarin, C. deliciosa (Tenor); lemon, C. limon; (L.); citron, C. medica (L.); lime, C. aurantifolia (Christm); rough lemon, C. jambhiri (Lush) and sour orange, C. aurantium (L.) were cultured on MS medium supplemented with different concentrations of BA (0.5,1.0 and 2.0 mg/L) alone or in combination with NAA (0.5 mg/L) for shoot multiplica-tion. The results indicated that somatic embryogenesis-derived plantlets can be suc-cessfully propagated in vitro with a good vigor compared with germinated seedlings. A large number of proliferated shoots were produced when these explants were cul-tured on MS medium containing 0.5mg/L of BA combined with 0.5mg/L of NAA. Most obtained shoots were rooted on half-strength MS medium containing 0.5 mg/L of NAA. These in vitro grown plantlets were then successfully transferred to green house through acclimatization process.
Показать больше [+] Меньше [-]SURVIVABILITY OF ESCHERICHIA COLI 0157:H7 AND NON- 0157 SEROTYPES ISOLATED FROM SOME DAIRY PRODUCTS UNDER STRESS CONDITIONS Полный текст
2006
Zeinab I. Sadek
Microbiological assay of 150 samples of dairy products for the incidence of Co-liforms, E. coli, E. coli 0157:H7 and non-0157 E.coli, show the recovery of the Coli-forms and E.coli from the tested products with different incidence percentage. Strains of E. coli 0157:H7 and non-0157 E .coli were recovered from 9 (6%) and 13(8.6%) of the total samples, respectively. The behaviour of these isolates were tested when exposing to low pH, salt, low holding temperature and heat treatment. The results indicate obvious survival of E. coli 0157:H7 and non-0157serotype with pH as low as 3.8 pH for 5 days. Also, survival or even multiplication in TSB con-taining <6% salt. Moreover, the strains remained viable at low holding temperature (5oC). So, the product which contaminated with this pathogens remain hazardous even under such stress condition. Decimal reduction times (D-values) of cells sus-pended in saline solution, TSB medium, reconctituted dry milk and chocolate milk were determined. The greatest survival as evidenced by highest D and Z values oc-curred with chocolate milk. Product composition and type of strain affected the heat lethality rates.
Показать больше [+] Меньше [-]