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ASSESSMENT OF THE ENTOMOPATHOGENIC FUNGUS BEAUVERIA BASSIANA SAUDI ARABIAN ISOLATE (B - SA3) AGAINST THE DEVELOPMENTAL STAGES OF THE RED PALM WEEVIL, RHYNOCHOPHORUS FERRUNGINEUS (OLIV.)
2009
The efficacy of the entomopathogenic fungus Beaveria bassiana Saudi Arabian isolate (B-SA3)was evaluated against the red palm weevil, Rynochophorus ferrungineus (Oliv.).The mentioned isolate was assessed on the different developmental stages of the red palm weevil through toxicity tests, i.e. determination of lethal concentration and lethal times to kill 50% of treated insects. The results showed that 8th instar larvae were the most tolerant followed by pupa to B.bassiana as their LC50 values were 3.75x 108 and 3.78x 107 conidia/ ml, respectively. Meanwhile, 4th instar larvae were the most susceptible to infection by B.bassiana (B-SA 3), as LC50 value was 3.25x 106 conidia/ ml, which proved insignificantly different to that determined in adult weevils, i.e. 4.18x 106 conidia /ml. Furthermore, LT50 values were very similar in these latter mentioned developmental stages in any considered concentration; meanwhile, LT50 was much longer in 8th instar larvae than the other considered instar and/or developmental stages. The fungus B. bassiana was most virulent to eggs of the red palm weevil as none of the eggs hatched following their treatment with any of the considered concentrations (ranging between 5x 109 to 5x105 conidia /ml). Moreover, germination viability of harvested conidia of B.bassiana stored at -4°C was insignificantly affected up to the 10th month storage period and was well above 90%. However, germination percentage of conidia then decreased to 70.27% after 16 months of storage. Also, the virulence of the stored conidia was tested after 1, 6, 12 and 16 months on adult red palm weevils, the LC50 values were 3.75x106, 4.66x106, 4.17x107 and 3.37x108 conidia/ ml, respectively. These results show that there was a significant decrease in the virulence of the tested fungus when the duration of storage period was more than 10 months.
Afficher plus [+] Moins [-]DISAPPEARANCE OF AZOXYSTROBIN, CYPRODINIL, FLUDIOXONIL, FENHEXAMID AND MYCLOBUTANIL IN STRAWBERRY FRUITS UNDER FIELD CONDITIONS
2009
A field experiment was carried out at Nubariah region Alexandria desert road located at 120 Km from Cairo, (Egypt) during 2005-2006 to study the degradation rates of five fungicides azoxystrobin, cyprodinil, fludioxonil, fenhexamid, and myclobu-tanil in strawberry fruits after application with their recommended rates under field conditions. The samples were collected in successive intervals after spraying and transported to Bioforsk refer-ence Lab, Ǻs, Norway for analysis by GC/MS. The fungicide residues on strawberry showed different degradation rates after treatment, with first-order kinetics. Half-lives (t0.5) were 1.92, 4.99, 3.68, 6.02 and 5.17 days for azoxystrobin, cyprodinil, fludioxonil, fenhexamid and myclobutanil, respectively.
Afficher plus [+] Moins [-]STUDIES ON NEEM SEED KERNEL EXTRACTS AS OVIPOSITION DETERRENTS AND OVICIDAL COMPOUNDS FOR THE COTTON LEAF WORM MOTHS, Spodoptera littoralis (Boisd.)
2009
H.A Gomaa
Mated female moth of the cotton leafworm, S. littoralis laid a total number of 1564.22 eggs during its whole life. In a free choice test, treating N. oleander leaves (as an oviposition site) with an aqueous extracts of neem seed kernel solutions extracted by different organic solvents reduced the number of deposited eggs on it. The lowest number of eggs was recorded when methanol was used for extraction, followed by chloroform, and the highest was, however, obtained after using benzene, butanol and ethyl acetate. The number of deposited eggs decreased as the concentration of any tested neem extract increased to reach the minimum at 0.2%. This means that the most deterred neem seed kernel extract is that which extracted with methanol at the concentration of 0.2%.Hatchability percentage of S. littoralis eggs greatly affected by the type of organic solvents used for neem extraction and the concentration of each extract on treated N. oleander leaves. The lowest hatchability was recorded after using methanol, followed by chloroform.On the other hand, an increase in neem seed kernel extract concentration caused an obvious decrease in egg hatchability.
Afficher plus [+] Moins [-]CHANGES OF SOME SOIL PHYSICAL AND HYDROPHYSICAL CHARACTERISTICS IN RESPONSE TO DIFFERENT SPRINKLER TYPES AND NOZZLE SIZES
2009
Walaa El-Shalakany | M.O El-Zakaziky | A.M. El-Araby | E.A. El-Sahhar | Y.E Arafa
Soil characteristics' degradation had been considered as one of the most important problems that face the agricultural development processes under arid and semi-arid conditions due to non-suitability of the applied technologies and techniques, attributed to management considerations. Consequently, higher crop yield and quality reduction had been occurred due to the degradation of the plant healthy media (soil). Therefore, the goal of this investigation was to monitor the change detection of some soil physical and hydrophysical characteristics under sprinkler irrigated agriculture. However, the terminal objectives were to evaluate and monitor some soil characteristics changes (soil bulk density, hydraulic conductivity and soil penetration resistance) under different mode of action of sprinkler types (rotating and impact sprinkler) and corresponding nozzle sizes (small and large sizes). Hereby, field experiments were carried out for two seasons (2006 and 2007) in the Desert Experimental Farm of Faculty of Agriculture, AinShamsUniversity which is located at El-Bustan region, Behaira Governorate. Results revealed that soil characteristics were highly affected with the sprinkler mode of action and corresponding nozzle sizes. However, a power function proportion of soil penetration resistance with respect to applied rotating and impact sprinkler types and corresponding small and large nozzle sizes, had been observed and analyzed. Therefore, data analysis speculated that, selection of the appropriate sprinkler types under diverse field conditions and situations such as: crop type and design criteria of sprinkler irrigation systems, have to be considered for good agricultural development processes under Egyptian newly reclaimed regions.
Afficher plus [+] Moins [-]EVALUATION OF RED CABBAGE ANTHOCYANIN PIGMENTS AND ITS POTENTIAL USES AS ANTIOXIDANT AND NATURAL FOOD COLORANTS
2009
H M. Sror | E Rizk | A. Azouz | Lobna A.M. Hareedy
Anthocyanins derived from red cabbage were extracted, and identified by using HPLC. These pigments are used as alternative natural red colorants in some processed foods i.e.; hard candy; jelly and ice sherbets. They are also effect of using as natural antioxidant on sunflower oil. Red cabbage has 90.5 mg anthocyanin /100 gm on fresh weights. Where the major constituents were cyaniding-3-diglucoside-5-glucoside (80%) and cyanidin 3, 5 diglucoside (20%) with HPLC. The best carrier for red cabbage anthocyanin pigment was found to be dextrin followed by cellulose, soluble starch and glucose respectively. On the other hand, color and higher pigment stability of anthocyanin derived from red cabbage were in acidic condition at pH ranged between 1.0 to 4.0 and in temperatures ranged between 40 to 80ºC. Meanwhile, the degradation of anthocyanin being 10% of total pigments after 180 min at 100ºC. Antioxidant activities of red cabbage anthocyanin were assessed by determining peroxide value on sunflower oil during 7 days at 60ºC. Sunflower oil contained 200 ppm red cabbage extract showed lower peroxide value being (9.92) than using 200 ppm synthetic antioxidant (BHT) (10.12) meq/Kg. Analysis of variance for sensory evaluation of prepared hard candy, jelly and ice sherbets indicated that, hard candy, jelly contained 0.10% and ice sherbets contained 0.20% red cabbage anthocyanin pigments revealed the highest score of color, taste, odor and overall acceptability similar with synthetic color (carmine).
Afficher plus [+] Moins [-]CHEMICAL AND TECHNOLOGICAL EVALUATION OF SOME SWEET POTATO VARIETIES
2008
El-Bastawesy Amal | Lobna A. Hareedy | Mervat M. EL-Far
This investigation was carried out to evaluate the chemical characteristics of new eight sweet potato varieties namely, CEMSA 74-228, SANTO AMARA, NC 1525 and KEMB 37 (creamy flesh) and JAPON TRESMESINO, LO 323, TAINUNG 64 and BEAUREGARD (yellow flesh ), and study their suitability for processing. The obtained re-sults reveal that SANTO AMARA and KEMB37 varieties were the best ones having the highest content of chemical constituents compared with those of the other studied creamy flesh sweet pota-to varieties. Moreover, 140 days from planting was the best harvesting time that achieved the highest chemical characteristics. All selected creamy sweet potato varieties had adequate miner-als contents especially, KEMB 37 followed by NC 1525 and CEMSA 74-228 then SANTO AMARA varieties that could be considered good sources of minerals for human nutrition. Yellow flesh sweet potatoes have been recognized as valuable sources of carbohydrates, protein, dietary fibers and could be considered as good sources of both vitamin C and total carotenoids. Moreover, TAINUNG 64 and LO 323 were found to be good sources of β-carotene (pro- vitamin A). The more suitable har-vesting time for yellow sweet potato varieties, which recorded the highest levels of essential ele-ments, was 140 days from planting. On the other hand, TAINUNG 64 variety could be considered the best one compared to the other examined vari-ties. The most suitable varieties that having good quality attributes for processing were SANTO AMARA and KEMB 37 as creamy flesh and TAINUNG 64 and BEAUREGARD as yellow flesh sweet potato varieties. Moreover, these va-rieties could be successfully used in the produc-tion of new and untraditional sweet potato prod-ucts.
Afficher plus [+] Moins [-]EFFECT OF VAPOR GARD AND CALCIUM CHLORIDE TREATMENTS ON KEEPING QUALITY OF NAVEL ORANGES AT DIFFERENT STORAGE TEMPERATURES
2008
Hanafy Ahmed A.H | H.M. Rashad | Samia, G. El-Oraby | F El-Wakil
The experiments were conducted in two suc-cessive seasons (2004 - 2005) on Washington Na-vel orange fruits to study the effect of cold storage conditions on reducing postharvest losses and im-proving keeping quality for the export mar-ket.Fruit samples were obtained from El–Fayoum governorate, Egypt and treated with vapor gard (VG) 2%, calcium chloride (CaCl2) 4% or vapor gard 2% + calcium chloride 4%. Fruits were stored at 2 or 8 ºC for 60 days and the last group was stored at 2 ºC for 30 days and transferred to be stored at 8ºC for another 30 days at R.H. 85-90%.The results revealed that during storage fruits treated with Vapor gard (2%) alone or with calci-um chloride (4%) + Vapor gard (2%) had been in good quality as well as it caused a pronounced increase in peel color and fruit firmness, while fruit weight loss and juice percentage were de-creased. In addition, it caused a significant in-crease in ascorbic acid, total sugar and calcium concentration, but there is no significant effect in T.S.S. / acid ratio. While, free amino acid, total soluble phenols and free proline concentrations were decreased. Furthermore, the fruits storaged at 2º + 8ºC caused a pronounced increase in fruit firmness, while fruit weight losses, juice percent-age and peel color were decreased. Also, it caused a pronounced decrease in T.S.S. / acid ratio, total sugar, total free amino acid, total soluble phenols and free proline concentrations, but there is no significant effect on calcium concentration. In addition, there is an increase in ascorbic acid con-centration. Generally, the results revealed that Vapor gard either alone or combired with calcium chloride dipping treatments and stored at 2º + 8ºC had better results in improving fruit quality and decreasing total fruit losses compared with control or calcium chloride treatment alone at other stor-age temperatures and this was also accompanied by changes in various metabolic and physiological processes of orange fruits.
Afficher plus [+] Moins [-]EVALUATION OF PERFORMANCE OF DAMASCUS GOAT AND ITS CROSSES WITH EGYPTIAN BALADI AND BARKI
2008
Khallouf N | Manal Elsayed | Mona, A. Osman
A total of 3108 records on conception rate (CR) and 2123 on litter size (LS) were used in this study. CR data represented 1600 Damascus (D) does, 201 Barki (BR) does, 229 Baladi (BL) does and 1070 crossbred does between D and each of BR and BL, while LS represented 1070 D does, 128 BR does, 145 BL does and 775 crossbred does. These records were used to study the effect of crossing and other fixed effects and to estimate heritability of these two traits in the Damascus goats. Statistical models included varying combination of the fixed effects of station, genotypes within station, year of mating, month of mating, and parity and the random effect of animal nested within station, genotype, year of mating and month of mating. Variance and covariance components for Damascus data were estimated through the Gibbs Sampling technique using a model that included the fixed effects of station, year and month of mating and parity, and the random effects of doe additive genetics and permanent environmental. CR mean in different analyses ranged from 0.39 to 0.63. Damascus, with a range of CR of 0.48 to 0.63, surpassed both local breeds (ranging from 0.33 to 0.58) and was close to the crossbreds that ranged between 0.34 and 0.68. LS mean ranged from 1.26 to 1.50 in different analyses. Baladi scored the highest in LS (1.49). Damascus ranged from 1.15 to 1.24 in different locations. LS ranged from 1.37 to 1.67 for crossbreds. For both traits there was no clear evidence of the merit of Damascus goats or their crosses over the Barki and Baladi goats. More data taken under sound herd management are needed to clarify the utility of the Damascus and its crosses. Heritability estimates+SE for CR and LT in Damascus goats were 0.03 ± 0.003 and 0.04 ± 0.003, respectively.
Afficher plus [+] Moins [-]Food Technology Research Institute, Agricultural Research Center, Giza, Egypt
2008
Ayman E. M | Nadia M. Abd El-Motaleb | Nadia H. Assem
Day by day increase the importance of using the natural food additives. Hence in this study, the phenolic extracted from basil leaves, spearmint leaves and fennel seeds, as natural antioxidants, were added at concentrations 200, 400 and 600 ppm from fat weight using in biscuit production. Biscuit was stored at room temperature for 8 months. Induction period was measured by Rancimat apparatus. Total phenolic and phenolic acids were determined. Peroxide value, acid value, thiobarbituric acid and refractive index were measured during storage. Antimicrobial activity of phenolic extraction were examined after 8 months. Sensory evaluation was measured directly after baking. The results showed that total phenolic content in basil leaves, spearmint leaves and fen-nel seeds were 3.97, 1.91 and 1.53 mg/g as caffeic acid equivalents respectively. Five phenolic acids were found in both basil leaves and spearmint leaves, while four phenolic acids were found in fennel seeds as determined by using HPLC. Rancimat results showed that induction period for phenolic herbs could be ranked as follow: basil leaves > spearmint leaves > fennel seeds. The re-sults elucidated that the best concentration from natural additives as antioxidants activity were 400 and 600 ppm compared with BHT. The results revealed that with increasing the concentration of natural antioxidants increased, the more peroxide value, acid value, thiobarbituric acid and refractive index were decreased. Total bacterial count and (yeast & mold) count were decreased with increas-ing the concentration phenolic additives. Sensory evaluation indicated that addition of different anti-oxidants showed no significant differences be-tween control and biscuit samples
Afficher plus [+] Moins [-]USE OF SOME VOLATILE OILS AS ATTRACTIVE AGENTS TO INCREASE FOOD CONSUMPTION IN HONEYBEE COLONIES
2008
Alqarni A.S | F J Alatawi
The present work aimed to investigate the stimulating and attractive effects of five volatile oils on honey bee colonies food consumption. These oils were added to sugar syrup and pollen substitutes. The consumption of sugar syrup and percentage of dead bees in caged honeybee work-ers were determined. Multi-choice test inside the honey bee colonies was carried out to determine the food consumption rate from different pollen substitutes. Positive effect was recorded by adding Coriander oil 0.03% followed by Fennel 0.15% and Spearmint oils 0.03% while nigella oil showed a repellent effect on honey bee workers. The mor-tality percentage was very low with no significant differences between treatments. Results indicated that addition of 5% pollen grains and three volatile oils increased significantly pollen substitute’s con-sumption. The highest consumption rate was rec-orded with coriander oil 0.03%. Results obtained indicated that the consumption of diets that con-tain Coriander, Fennel, and Spearmint volatile oils was more successful than control.
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