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MONITORING OF PESTICIDE RESIDUES IN SOME ENVIRONMENTAL ELEMENTS AT MENOFIA GOVERNORATE, EGYPT 全文
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.
显示更多 [+] 显示较少 [-]IN VITRO PROPAGATION OF SOMATIC EMBRYOGENESIS-DERIVED PLANTLETS OF CITRUS 全文
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.
显示更多 [+] 显示较少 [-]SURVIVABILITY OF ESCHERICHIA COLI 0157:H7 AND NON- 0157 SEROTYPES ISOLATED FROM SOME DAIRY PRODUCTS UNDER STRESS CONDITIONS 全文
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.
显示更多 [+] 显示较少 [-]A NEW TECHNIQUE FOR GRAPE INSPECTION AND SORTING CLASSIFICATION 全文
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.
显示更多 [+] 显示较少 [-]SOME PHYSIOLOGICAL AND HISTOPATHOLOGICAL EFFECTS OF TWO PESTICIDES AGAINST THE COTTON LEAF WORM, SPODOPTERA LITTORALIS (BOISD.) 全文
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.
显示更多 [+] 显示较少 [-]RECOGNITION OF CERTAIN KAIROMONES BY THE PARASITOID TRICHOGRAMMA SPP. IN EGGS OF IT’S HOST CYDIA POMONELLA 全文
2006
Sakr, H.E.A.
A kairomone from adult Cydia pomonella L. scales is an important factor in the host recognition and searching behaviour process of Trichogramma cacoeciae Mar-chal and Trichogramma dendrolimi Matsumura. The Trichogramma spp. used the chemicals from the host eggs for orientation to host and increased their parasitism. The females of T. cacoeciae*, T. dendrolimi** and T. dendrolimi*** contacted the unwashed host eggs significantly longer than the washed eggs. Washing the codling moth eggs with hexan significantly reduced the parasitism of all the tested Tricho-gramma strains compared to unwashed eggs. The treated apple trees with wing scales of C. pomonella had significant influence on the parasitism compared to un-treated trees. The percentage parasitism of codling moth eggs on the treated trees (31.6%) was significantly higher than on the untreated trees (19.3%).
显示更多 [+] 显示较少 [-]SURVEY OF MITES ASSOCIATED WITH GRAIN RESIDUES AND MIXED FLOUR IN WAREHOUSES AND MILLS IN GREAT CAIRO 全文
2006
A.E.A Mahgoob | A.I. Badawy | I.M Badoor
Twenty one mite species belonging to 3 suborders and 11 families were found in grain residues and mixed flour samples collected from warehouses and mills at Great Cairo. They were 12 pest species, 7 predatory and 2 parasitic species. Species commonly found in all inspected materials at all locations were Dermatophagoides farinae Hughes, Tyrophagous putrescentiae (Sch.) and Cheyletus malaccensis Oud. However Acrus siro (Lin), Acarophenax tribolii (New.) and Pyemotes herfsi (Oud.) were often abundant. The remaining species occurred sporadically in the collected materials. Actinedid and acaridid mites were “dominant” and “constant” in mixed flour and grain residues samples, the second group was the most abundant. Whereas gamasid mites was “recedent” and “accidental”. Mixed flour taken from Qaliobia Governorate harboured the highest number of mite species (15 species) followed by grain residues from Giza Governorate (13 species). While grain residues taken from Cairo Governorate harboured the lowest number (5 species).The highest infestation level with mites (2677.3 individuals) was recorded in mixed flour at Qaliobia Governorate, while the lowest one (1067 individuals) was found in grain residues at Cairo Governorate. Generally, mixed flour harboured more mite species than grain residues. Most of the collected mite species occurred during autumn and winter except P. herfsi and A. tribolii which were recorded during spring and summer, respectively. Dominance and frequency of occurrence, population fluctuations, effect of temperature and relative humidity on the population dynamics, also the relation between the predators and pests of mites were discussed in details.
显示更多 [+] 显示较少 [-]LARVAL PARASITOIDS OF THE POTATO TUBER MOTH Phthorimaea operculella IN POTATO AND TOMATO FIELDS 全文
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
显示更多 [+] 显示较少 [-]ROOT ROT DISEASE OF OLIVE TRANSPLANTS AND ITS BIOLOGICAL CONTROL 全文
2006
M.S. Mousa, | M.K. Ali | A.A. Mosa | I.S Elewa
Several nurseries of olives in Fayoum and Giza were surveyed for root rot incidence during early summer of 2003. In Fayoum, root rot incidence reached 53% while in Giza, disease incidence was 44%. Disease symptoms consist of partial wilting, leaves browning and twig dieback, which was associated with severe root rot and basal stem cankers and followed, in most cases, by plant decline and death. The most frequently isolated fungi from rotted roots were Fusarium oxysporum, F. solani, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Cylindrocarpon sp. and Alternaria alternata. Isolation frequency of different fungi varied among olive cultivars. Generally, Fusarium spp. were the most frequently isolated pathogens and Fusarium oxysporum was the most frequent (35.5%) on all cultivars followed by F. solani (19.3%) R. solani (16.1%). Meanwhile, S. rolfsii, F. moniliforme, Cylindrocarpon sp. and A. alternata occurred at lowfrequencies. Pathogenicity tests showed that all tested isolates caused varied degrees of root rot symptoms on olive transplants, cvs. Manzanillo and Picual. Fusarium oxysporum, F. solani and R. solani caused the highest root rot incidence and severity on both cultivars. There was a positive correlation between disease severity on roots and severity of foliar symptoms. All evaluated olive cultivars were susceptible or extremely susceptible to fungal pathogens. All cultivars showed high disease severity with root rots, especially in response to infection by F. solani, F. oxysporum and S. rolfsii. However, the least foliar symptoms were recorded on cultivar Coratina. Application of two commercial biological control products (Rhizo-Plus and Trichoderma 2000) to soil, 24h before planting olive cuttings in the nursery, significantly reduced incidence of root rot on transplants of cultivars Manzanillo and Picual, up to 28 weeks after planting
显示更多 [+] 显示较少 [-]PROLINE ACCUMULATION IN DURUM WHEAT (Triticum durum Desf) UNDER WATER DEFICIT 全文
2006
Chaib, Ghania | M. Benlaribi
Proline’s content was estimated in different organs of durum wheat; dry wheat seeds (caryopsis), seeds during germination, second and third leave’s level in different degrees of water alimentation: 75%, 50.0, 42.5, 35.0, 25.0 and 12.5% of the field capacity. Four genotypes of durum wheat Triticum durum DESF were studied from three different origins; Algeria, France and Mexico. Results showed that proline’s content was low in dry wheat and in seeds during germination, and increased by decrease of water supplies. This amino acid estimation during experimentation, allowed us to classify the studied genotypes into 3 main groups: - Genotypes with high proline accumulation (Mexicali). - Genotypes with low proline accumulation (Clairdoc). - Two intermediate genotypes MBB and OZ. These differences among genotypes can be exploited in parietal selection with relation towater deficit.
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