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MONITORING OF PESTICIDE RESIDUES IN SOME ENVIRONMENTAL ELEMENTS AT MENOFIA GOVERNORATE, EGYPT
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.
Afficher plus [+] Moins [-]PREPARATION AND PROPERTIES OF PROBIOTIC FROZEN YOGHURT MADE WITH SWEET POTATO AND PUMPKIN
2006
Gehan A.M. Hussein | I.E. Aumara
Low-fat frozen yoghurt was made by using commercial probiotic (Lactobacillus acidophilus, Streptococcus thermophilus & bifidobacteria) and traditional (Lactoba-cillus delbrueckii ssp. bulgaricus & Streptococcus thermophilus) starters; as well as; roasted red sweet potato and pumpkin for enhancing nutritional and functional val-ues of this products. The preparing mixes and resulting frozen yoghurt stored at -20ºC for 8 weeks were evaluated for physicochemical, bacteriological and organo-leptic properties. The results revealed that, there was significant differences (p<0.05) in all properties studied among the mixes and resulting frozen yoghurt. Frozen yoghurt mixes made with traditional yoghurt starter and sweet potato had higher specific gravity, weight per gallon, freezing point and apparent viscosity, but lower in pH values than the mixes made with probiotic starter. Also, resulting frozen yoghurt prepared with traditional starter and sweet potato had higher specific gravi-ty, weight per gallon, freezing time, melting resistance and acetaldehyde content, but lower in overrun % and diacetyl content than that made with probiotic starter. Counts of Lb. delbrueckii ssp. bulgaricus, Str. thermophilus (traditional starter) and Lb. acidophilus were the most numerous in pumpkin frozen yoghurt, followed by sweet potato frozen yoghurt. On the other hand, sweet potato frozen yoghurt had higher Str. thermophilus & bifidobacteria (probiotic starter) counts, than the other treatments. However, frozen storage for 8 wk was slightly effected on the viable bacterial counts determined of different frozen yoghurt treatments, and bifidobacte-ria counts were still higher along the storage period than the recommended mini-mum levels. Also, frozen yoghurt manufactured with probiotic starter; especially with sweet potato; had the highest total organoleptic scores. Therefore, low-fat fro-zen yoghurt with improved nutritional and functional values, and also good organo-leptic properties could be made by traditional yoghurt and probiotic starters; as well as roasted red sweet potato and pumpkin.
Afficher plus [+] Moins [-]A NEW TECHNIQUE FOR GRAPE INSPECTION AND SORTING CLASSIFICATION
2006
Elbatawi I.E | M.T. Ebaid
Sorting and classification of fruits are the main problem specially for Superiorand King Ruby varieties which represent more than 50% of grape production inEgypt. A usual procedure to carry out this task is based on human visual inspectionconsidering general fruit attributes like color, size, shape, firmness and sugar contentof grape cluster. Color contains important information about fruit status and in somecases it is decisive for fruit quality differences. This paper provides a new techniqueto investigate the applicability of color classification, sugar content and firmness ofgrape. Standard RGB color chart, artificial neural network and a potential of nearinfrared(NIR) reflectance as a means for nondestructive measurements of grapefirmness and sugar content were used. NIR spectral data were collected from the twovarieties of grape in the spectral region between 800 nm and 1700 nm. Statisticalmodels were developed using the partial least square method to predict the firmnessand sugar content of grape. The models gave relatively good predictions of thefirmness of both Superior and King Ruby, with corresponding r values of 0.80 and0.65. The NIR models gave excellent prediction for grape sugar content with valuesof 0.71 % and 0.65 % Brix for Superior and King Ruby, respectively.
Afficher plus [+] Moins [-]EFFICIENCY OF HOST RESISTANCE AND FUNGICIDE APPLICATION FOR CONTROL OF POTATO LATE BLIGHT
2006
El-Shimy A.O. | Tomader, G. Abdel-Rahman
Late blight caused by Phytophthora infestans is one of the most destructive dis-eases potato in Egypt and world wide. Stability of resistance to late blight was eva-luated in twenty five potato cultivars during 2003 and 2004 successive seasons un-der heavy natural infection. Data showed that the potato cultivars Altesse, Occania, Safrane and Soleia highly resistant while cultivars Daisy, Hermine and Isabel rec-orded the highest susceptibility to late blight. Application different fungicide against potato late blight revealed that Aquagen Bro and Previcur-N were the best effective fungicides in reducing disease severity and progress of late blight. Data showed also that the losses of tubers due to late blight in season 2003 ranged from 11.75 Kg/plot (cultivar Hermes) to 18.0 Kg/plot (cultivar Lady Roseta) while in season 2004, yield losses ranged from 11.25 Kg/plot (cultivar Hermes) to 23.75 Kg/plot (cultivar Spun-ta). The results demonstrate that integration of Previcur-N treatment with host resis-tance was effective in reducing late blight and tuber yield loss of potato.
Afficher plus [+] Moins [-]RELATIVE ADVANTAGE OF WEED CONTROL METHODS APPLIED IN SPRINKLER AND DRIP IRRIGATED SYSTEMS IN TOMATO CULTIVATIONS IN EGYPT'S NEWLY RECLAIMED LANDS
2006
Sahhar E.A. | K.F. El-Bagoury
This study, based on a collaborative project with the Regional Council forResearch and Agricultural Extension, was carried out at an experimental farm of asandy soil belonging to Faculty of Agriculture, Ain Shams University, El-BustanRegion, Beheira Governorate, during two seasons (2004&2005) on an area of 5850m2. The experiment was designed in a split plot, arranged in a randomized completeblocks with three replications. Irrigation operations [Drip(DI)/Sprinkler(SI)] wereassigned to the main plots, while weed control methods (hoe weeding/herbicide usedthrough either conventional spraying with 0.300kg/fed concentration or herbigationwith three herbicide concentrations of 0.150, 0.225 and 0.300kg/fed.) were assignedto the subplots. The data were statistically analyzed by the Least Squares Methodusing a model involving the two factors (irrigation system and weed control method)and their interaction as affecting eradication percent, tomato yield/fed., and cost ofcontrol operation. The effect on herbicide residues in the tomatoes was alsoinvestigated
Afficher plus [+] Moins [-]EFFECT OF PASTEURIZATION AND STORGE ON FLAVOUR OF APPLE AND KIWIFRUIT BLEND JUICE
2006
Magda A. Abd El-Mageed | Emad El-Din Ragheb
A blend Juice prepared from apple juice and kiwifruit juice (60:40 v/v), was pas-teurized and stored for 3 and 6 months at 4o and 25oC untill analysis. Sensory evalu-ation showed significant differences between the fresh and pasteurized blend juice in all sensory attributes. The headspace volatiles of fresh apple, fresh kiwifruit, fresh and stored pasteurized blend juice at different temperatures were collected and sub-jected to GC and GC-MS analysis. A total of 33 volatile components were identi-fied, 18 esters (17 aliphatic and one aromatic), 6 alcohols, 3 aldehydes, 3 terpenic hydrocarbons, 2 ketones and 1 carboxylic acid. The volatile components in the pas-teurized blend juice showed considerable quantitative and qualitative variations dur-ing storage. By comparative study between the blend juice and fresh apple, fresh kiwifruit juices it was clear that the pasteurization process caused a remarkable in-crease in the total esters content due to the high increase in methyl propanoate, me-thyl butanoate and methyl benzoate. Pasteurization caused a sharp decrease in buta-nol which is the most abundant compound in fresh apple juice. All alcohols showed the same trend except ethanol. Pasteurization revealed a remarkable decrease in (E)–2-hexenal which is the most abundant compound in fresh kiwifruit juice. Regarding the effect of storage it was noted that the blend juice stored at 4oC showed high qual-ity after 3 months due to the remarkable increase in the contents of total ester, buta-nol, and (E) –2- hexenal with a decrease in limonene, but after 6 months the good quality was attributed to the high increase in ethyl butanoate concentration. While stroage at 25oC showed good quality after 3 months due to the very high increase in total esters content which attributed to a greate increase in ethyl butanoate concen-tration (which gave sweet and fruity aroma to juice), but storage for 6 months gave rise to a sharp decrease in ethyl butanoate which led to a high loss in aroma quality.
Afficher plus [+] Moins [-]SOME PHYSIOLOGICAL AND HISTOPATHOLOGICAL EFFECTS OF TWO PESTICIDES AGAINST THE COTTON LEAF WORM, SPODOPTERA LITTORALIS (BOISD.)
2006
Youssef L.A.
The toxicological effect of two pesticides, pyriproxyfen and abamectin were eva-luated on third instar larvae of the cotton leafworm, Spodoptera littoralis (Boisd.). According to the estimated toxicity values, i.e. LC50, LC90 and slope values, the chemical abamectin showed that it was slightly more toxic than pyriproxyfen. The effect of these two insecticides, at the determined LC50 and LC25 values on the di-gestive physiology of treated larvae, as indicated by some nutritional indices was conducted. Obtained results demonstrated that pyriproxyfen and abamectin caused a significance reduction in growth of treated larvae as depicted by larval weight gain Also, a significant decrease was found in the efficiency of ingested food to body matter and efficiency of conversion of digested food to body matter as compared to untreated insects. These effects were generally more evident when abemectin was used. The two tested compound also caused histological changes in the midgut of treated larvae, in form of disruption in the columnar epithelium cells and stretching leading to tearing in the peritrophic membrane. This observation might explain the impairment in nutritional indices in treated larvae as compared to the control.
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