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MONITORING OF PESTICIDE RESIDUES IN SOME ENVIRONMENTAL ELEMENTS AT MENOFIA GOVERNORATE, EGYPT Full text
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.
Show more [+] Less [-]NATURAL OCCURRENCE OF CITRININ AND BIOCONTROL OF ITS PRODUCING FUNGUS BY Trichoderma hamatum IN RICE GRAINS Full text
2006
Ezzat S.M. | E.F. Abd-Allah
Paddy rice was sampled from El-Sharkia, El-Gharbia, El-Dakahlia and Kafr El-Sheikh governorates, Egypt. Of the 29 samples taken, ten were contaminated with the mycotoxin citrinin. An average of 6.79 x 104 fungal spores per gram rice was found. The isolated fungi represented 47 species belong to 28 genera. The predomi-nant genera were Aspergillus, Cladosporium and Penicillium. Aspergilli were represented by 22 species; Aspergillus niger and A. flavus had the highest occur-rence. Penicillium viridicatum produced the highest amount of citrinin on glucose ammonium nitrate salts broth and rice grains and hence, this isolate was selected as a good producer of citrinin in this study. The presence of Trichoderma hamatum re-duced the amount of citrinin produced by P. viridicatum compared with its respec-tive control. The excessive growth of T. hamatum on P. viridicatum was increased with time. Viability of P. viridicatum conidia decreased by T. hamatum with an in-crease in the incubation period. Chitinases and 1,3-B-glucanase enzyme activity of T. hamatum increased with extending the incubation period on P. viridicatum cell walls up to maximum values at 72 and 84 h, respectively. T. hamatum led to a de-crease in the production of citrinin by P. viridicatum on rice grains compared with the respective control values.
Show more [+] Less [-]IN VITRO PROPAGATION OF SOMATIC EMBRYOGENESIS-DERIVED PLANTLETS OF CITRUS Full text
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.
Show more [+] Less [-]INFLUENCE OF TEMPERATURE ON THE DEVELOPMENTAL RATE AND REPRODUCTION OF THE ENGLISH GRAIN APH-ID, SITOBION avenae (FABRICIUS) (HOMOPTERA: APHIDI-DAE). Full text
2006
Salman A.M.A.
A laboratory investigation was conducted to study the effect of constant tempera-ture on some biological aspects of english grain aphid, Sitobion avenae (Fabricius). The present work was carried out in electrical incubators provided with photoperiod of 16 : 8 (L : D) and 55 – 60% R.H. Data revealed that the english grain aphid passed through four instars to reach maturity. The duration period of the nymphal stage was 19.0, 13.98, 11.96, 8.51 and 7.5 days at 12, 15, 18, 21, 24 °C, respectively. Developmental threshold of this stage is found to be 4.2 °C. The thermal units re-quired for complete one generation was 148 day – degrees. Life table parameters were as following : The reproduction rate (Ro) were 18.75, 30.72, 36.53, 44.21 and 32.42; mean generation time (GT) were 26.16, 21.23, 17.39, 11.92 and 9.86 days; population doubling time (DT) of the english aphid were 6.19, 4.29, 3.35, 2.18 and 1.96; intrinsic rate of increase (rm) were 0.1121, 0.1613, 0.2069, 0.3178 and 0.3528 and finite rate of increase (λ) were 1.119, 1.175, 1.229, 1.374 and 1.423 at 12, 15, 18, 21 and 24 °C, respectively. The results indicated clearly that the favourable range temperature for development and multiplication the english grain aphid be-tween 18 and 24°C.
Show more [+] Less [-]PREPARATION AND PROPERTIES OF PROBIOTIC FROZEN YOGHURT MADE WITH SWEET POTATO AND PUMPKIN Full text
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.
Show more [+] Less [-]GROWTH, YIELD AND YIELD COMPONENT OF INOCULATED CHICKPEA AND FABA BEAN PLANTS AS AFFECTED BY USING METHYLOTROPHIC BACTERIA Full text
2006
Sawsan Shehata | Wedad E.E. Eweda | H.H Abo Taleb | Heba O.M. Orf
Two pot experiments were performed in Giza research station, AgriculturalResearch Center (ARC) using 2 isolates of Pink-Pigmented FacultativelyMethylotrophic bacteria (PPFMs) originated from chickpea and Faba bean. Foliarapplication with PPFM isolates were conjugated with specific rhizobial inoculumand N-fertilization (15 Kg N Fed-1). Nodulation status, nitrogen fixation and growthyield and yield component were recorded. Results clearly indicated that Chickpeawas superior in its response to foliar application with PPFM.C. As it gave higherrecords of number and dry weight of nodules, dry matter and N-content of plants ascompared to Faba bean. A field experiment was also conducted in sandy loam soil atSouth EL-Tahreer province to investigate the effect of foliar application withPPFM.C strain + specific Rhizobia and N-fertilization on nodulation, growth andyield of chickpea legume plants. Results indicated that foliar application withPPFM.C in the presence of specific rhizobial inoculation scored significant increasesin economic turnover of chickpea in the range of 21-32% as compared to Nfertilizationat rate 50 Kg N Fed-1. Foliar application with 5 L Fed-1 in the presenceof 15 Kg N Fed-1 and specific rhizobial inoculation led to an increase of 518 kg fed -1productivity of seed yield , with economic turnover of 2491 L.E.
Show more [+] Less [-]A NEW TECHNIQUE FOR GRAPE INSPECTION AND SORTING CLASSIFICATION Full text
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.
Show more [+] Less [-]EFFICIENCY OF HOST RESISTANCE AND FUNGICIDE APPLICATION FOR CONTROL OF POTATO LATE BLIGHT Full text
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.
Show more [+] Less [-]PRODUCTION OF PROBIOTIC LOW-CALORIE SOUR CREAM Full text
2006
Fayed A.E. | Gehan A.M. Hussein | Azza M. Farahat
The production of probiotic low calorie sour cream was aimed to experiment in relation to its compositional, bacteriological, biochemical, rheological and organo-leptic properties along the cold storage period of the product. Cream based on 36% total solids (TS) and 30 % fat was made using the obtained fresh cream (54 % TS and 50 % fat) and liquid skimmed milk (9 % TS).To produce low-calorie sour cream, fat content was lowered to 20 and 10 % depending on the addition of Sim-plesse100® to mimic milk fat on the basic of 0.1% fat mimetic is instead of 1.0% fat. Dried whey protein concentrate (DWPC, 95 % TS) was used as bulking agent to overcome the loss occurred in the TS content due to the reduction in the fat content. Thereafter, all creams were homogenized at 55-60°C and further heat treated to 74°C for 30 sec. followed by rapidly cooling to the appropriate temperatures. Then creams were inoculated with 2% freshly prepared bacterial starter culture and incu-bated at 30 or 37 °C, to reach pH value about 4.6, for cream cultured with R-704 or ABT-2 type starter culture, respectively. The results indicated that, the proportional fat replacement of cream led to gradual increase in the protein, carbohydrate and ash contents, and decreased the caloric value. There are a backward relationship between the bacterial population and the fat content of the sour cream. Where, in the product cultured with ABT-2 type, Lactobacillus acidophilus grew and predominated in all other accompanying strains overlooking either the fat content or the cold storage pe-riod (CSP). Streptococcus thermophilus populated the 2nd predominance order fol-lowed by Bifidobacterium sp., which tended to proximate and preceded, actually, Str. thermophilus by prolonging the CSP of the lowest fat-content cream (10%). The increase rate of the bacterial count continued until 3rd weak for Lb. acidophilus and to 1st weak for Bifidobacterium sp.. Thereafter, gradual decreases were occurred. However, Str. thermophilus began to decrease from the 1st day of CSP. Although the count of bacterial type R-704 was always higher, it behaved a trend similar to that of Bifidobacterium sp. toward the CSP. Sour cream of ABT-2 type contained higher ti-tratable acidity (TA) % as well as lower pH, acetaldehyde (AC) and diacetyl (DA) values than that cultured with R-704 type. Along CSP of sour cream the increment in AC, DA and TA contents continued, in order, until the 7th , 14th and the end of theFayed; Gehan Hussein and Azza FarahatArab Univ. J. Agric. Sci., 14(2), 2006experimental period. As the protein content raised at the expanse of the fat content via adding DWPC, which was in the denatured form, the firmness, consistency coef-ficient, and yield stress of sour cream increased, especially when ABT-2 type was used and the CSP progressed. Furthermore, ABT-2 sour cream was sensory distin-guished with, nearly, similar appearance as will as better flavour and consistency ra-ther than that of R-704. The fat reduction to 20 % did not influence the overall sen-sory quality, while that of 10% fat attained panel score averaged 93.5 % of the con-trol when ABT-2 type was used. As a conclusion, it is successfully possible to pro-duce probiotic low calorie sour cream with excellent sensory attributes using Sim-plesse100® as fat mimetic and bacterial type ABT-2 as starter culture.
Show more [+] Less [-]RELATIVE ADVANTAGE OF WEED CONTROL METHODS APPLIED IN SPRINKLER AND DRIP IRRIGATED SYSTEMS IN TOMATO CULTIVATIONS IN EGYPT'S NEWLY RECLAIMED LANDS Full text
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
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