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Результаты 431-440 из 1,443
INTERCROPPED WITH GROUNDNUT ON GROWTH, YIELD AND YIELD COMPONENTS OF BOTH CROPS
2005
; A.A Zohry Sherif, Sahar A. | Ibrahim Sahar T.
Two field trials were carried out at South Tahrir Research Station (Ali- Moubark). These trials were conducted in 2003 and 2004 to evaluate three planting dates of maize (the over story shade crop) intercropped with groundnut i.e, on 1st June, 10th June and 20th June, and four plant densities of maize intercropped with groundnut, i.e, maize was spaced at 50 and 100 cm apart leaving one or two plants/hill. Groundnut (the main crop) was grown on all rows. The data obtained indicate that ear length, ear diameter, number of rows/ear, number of kernels/row and the weight of 100grains increased with increasing maize spacing as well as with diminishing the number of plants remained per hill after thinning (to one plant/ hill). On other hand dense planting resulted in higher yield of maize whether by narrowing maize spacing or increasing the number of maize plants per hill after thinning. Yield and yield components of maize were significantly decreased by delaying planting date of maize up to the latest date. Yield /fed and yield components of groundnut were associated with maize density and distribution. The more the shade offered by maize the less the values of these traits were obtained. Highest values were obtained when maize was spaced at 100cm. and thinned to one plant/ hill. Increases in the values of yield and yield components of groundnut were associated with delaying the planting date of maize. Delaying the planting date of maize resulted in increases in the values of land equivalent ratio (LER) and the relative crowding coefficient. The treatment effect at any planting date of maize exerted very low competitive pressure when aggressivity was measured. With delaying seeding maize, competitive ratio (CR) diminished to the least. Spacing maize at 50cm. apart and leaving two plants / hill after thinning resulted in highest value of LER and relative crowding coefficient (RCC). Nor any maize density had any heavy competitive pressure on groundnut when aggressivity was measured
Показать больше [+] Меньше [-]THE FEASIBILITY OF USING SOME WHEY PROTEINS CONCENTRATE PREPARATIONS IN MANUFACTURE OF INFANT FORMULA
2005
A.M. Hassan Fatma, | Khorshid M.A. | Abd El-Gawad Mona, A.M.
Different types of whey proteins concentrate (WPC) were prepared in Brewaster Dairy pilot plant at Ohio State Univ. USA and used for formulating an infant formula and compared with Alacen 841 (Commercial WPC) as control to select the best WPC preparations which succeed in manufacture of infant formula. Infant formula was prepared with different types of WPC (Alacen 841, UF 5x, UF4x, DF 8x and DF 4x). The ratio of WPC: sodium caseinate was 40: 60. Salt, sucrose, lecithin and vegetable oil were added then homogenized and sterilized after sealing at 121ºC for 6 minute, cooled in an ice bath and stored at room temperature. Samples were analyzed chemically and organoleptically when fresh and after storage at room temperature for three months. Emulsion volume index (EVI), viscosity, protein solubility, sedimentation and particle size were determined before and after sterilization. Results showed that EVI, viscosity, sedimentation and particle size increased after sterilization than before where as protein solubility take an opposite trend. Emulsion volume index, viscosity, sedimentation and particle sizes were increased after storage at room temperature for three months than fresh. Whereas proteins solubility deceased after storage than fresh. Statistical analysis showed high significant difference (α0.05) for emulsion volume index, protein solubility, viscosity, particle size and sedimentation.
Показать больше [+] Меньше [-]INDUCTION OF DEFENSE RESPONSES IN TOMATO PLANTS INOCULATED WITH PHYTOSTIMULATION MICROORGANISMS AGAINST Fusarium oxysporum
2005
M. Attia, | Hamed Hoda A.
Phytostimulation microorganisms (PSM) viz. Trichoderma harzianum (TH), Bacillus subtilis (BS) and arbuscular mycorrhizal (AM) fungi were tested individually or in mixed culture for their ability to induce pathogenesis-related (PR)-proteins (chitinase, β-1,3-glucanase, peroxidase, phenylalanine ammonia-lyase PAL) and phenolics in tomato plants grown in sterilized soilless medium artificially infested with or without the Fusarium oxysporum f. sp. radicis-lycopersici (FORT). PSM-treated plants were more developed than non-treated control or inoculation with FORT. PSM-treated plants were effective in reducing diseases produced by FORT infection. Plants application with PSM significantly increased the activity of peroxidase, chitinase, β-1, 3-glucanase and PAL and accumulated phenolics in tomato plants compared to untreated control. Among the treatments, AM fungi recorded the maximum increase in the activities of all defense–related enzymes and accumulated phenolics followed by T. harzianum and B subttilis. The maximum increase in the activities of peroxidase, β-1, 3- glucanase, PAL and accumulated phenolics were observed 6 days after application of PSM. However, the maximum increase in the activities of chitinase was observed 9 days after application of PSM. Several fold increase in the accumulation of phenolics and activities of defense enzymes was observed when the induced plants were inoculated with Fusarium oxysporum f. sp. radicis-lycopersici (FORT). These results suggest that enhanced activities of defense enzymes and elevated content of phenolics by inoculation with PSM may contribute to protection of tomato plants against F. oxysporum.
Показать больше [+] Меньше [-]MITES IN MARJORAM AND CHAMOMILE CULTIVATIONS IN FAYOUM AND THE RELATIVE ABUNDANCE OF TWENTY SIX SPECIES
2005
A.A.R. Rahil,
A study on mite species in marjoram and chamomile plantations in Fayoum was carried out during 2003 and 2004 seasons. Twenty-six species were found and divided according to their feeding habits into three major groups, phytophagous (7 species), predaceous (8 species) and a group of debatable feeding habits (11 species). Population density evaluation showed that Tetranychus urticae Koch was the main phytophagous mite on both hosts. The predatory mite Amblyseius cydnodactylon Shehata and Zaher was dominant on marjoram followed by Hemicheyletia bakeri (Ehara). From the debatable group, Pronematus ubiquitus Mc Gregor was the dominant followed by Tyrophagus putrescentiae (Schrank) and Paralorryia gizai El-Bagoury. On chamomile, the predatory mite Eupodes niloticus Abou-Awad & El-Bagoury was dominant and from the debatable group, Tydeus kochi Oud. was dominant followed by T. putrescentiae and P. gizai. Population densities were insignificantly affected by temperature and relative humidity.
Показать больше [+] Меньше [-]SUSCEPTIBILITY OF SOME TOMATO CULTIVARS TO BACTERIAL CANKER AND SPOT DISEASES AND THE ROLE OF SEEDS IN PATHOGEN TRANSMISSION*
2005
Z.A. Afaf El-Meneisy, | Abd El-Ghafar N.Y. | Abd El-Sayd Wafaa, M. | El-Yazeed A. Abo | Gamil Nagwa, A.M.
Bacterial canker caused by Clavibacter michiganensis subsp. michiganensis (Smith) and bacterial spot caused by Xanthomonas campestris pv. vesicatoria (Doidge) Dye have become important diseases of tomato in Egypt. The present work was planned to evaluate the reaction of different tomato cultivars and the role of seeds to transmit both pathogens. Cultivars of Dora, Flora-Dade, KTM141, Money Maker, Niagra, Super strain B hybrid and GS12 were moderately resistant to both diseases, but Castle rock, Peto 86 and Super strain B cultivars were susceptible. However, Castle rock, Peto 86, Super strain B and Niagra cultivars were highly susceptible for bacterial canker than spot disease. Using the Liquid assay method, C. michiganensis subsp. michiganensis bacterium could be detected in seeds of cultivars Dora, KTM141, Niagra and Super strain B hybrid, but X. campestris pv. vesicatoria was detected on seeds of cultivars GS12, Peto 86 and Super Marmand. However, both bacterial pathogens were not detected in seeds of all cultivars, except GS12, when direct planting method on selective media was used. In an in vivo assay, bacterial canker has developed more than bacterial spot disease on tomato seedlings produced from non-treated seeds. Bacterial canker has developed on all tested cultivars at different frequencies. Transmission of both pathogens occurred at high frequency by seeds of cultivars Niagra and Dora, however bacterial spot was not borne on samples of other tomato cultivars
Показать больше [+] Меньше [-]ISOLATION AND IDENTIFICATION OF Spiroplasma citri USING SOME SENSITIVE METHODS
2005
Mahrous Rasha M. | Moustafa T.A. | Galal Farag Azza | Sadik A.S. | El-Afifi Sohair I. | Gamal El-Din A.S.
Spiroplasma citri, the causal agent of stubborn disease, was isolated from leaves and fruits of diseased citrus plants and cultured on solid and liquid C3G medium. On the basis of mode of transmission, symptomatology, shape on solid medium, staining of infected plant tissues with Dienes’ stain and phase contrast microscopy, the isolated agent was identified as Spiroplasma citri. Identifiction was ensured by ELISA and PCR techniques. A fragment (1053 bp) from the spiralin gene of S. citri was amplified by PCR using two specific primers for the spiralin gene. The nucleic acid hybridization techniques (Southern and dot blots) were used for identification of the spiroplasmal genome using non-radioactive DNA probe specific for spiralin gene region. It was carried out as an alternative sensitive method for rapid detection of the Egyption isolate of S. citri using non-radioactive DNA probe specific for spiralin gene region.
Показать больше [+] Меньше [-]DIAGNOSING THE NUTRITIONAL STATUS OF APPLE ORCHARDS AT SOUTH OF JORDAN
2005
F Al-Nasir | K Al-Absi
A test survey was conducted to determine the nutritional status of apple trees grown at four highly productive orchards in south of Jordan. Leaf and soil samples were taken from each orchard, and analyzed for the concentrations of macro- and micronutrients. Soils of Al-Shoubak tend to have high pH, low organic matter and high CaCO3 contents. The results showed that soil concentrations of N, K, Fe, Mn, Zn and Cu varied widely among the orchards. No deficiency or hunger signs of N, P, K, Mn and Zn nutrients were observed at any of the localities since concentrations of leaf nutrients were generally within the sufficient range, indicating adequate lev-els of fertilization applied to the trees. The leaf analysis has shown that Cu deficien-cy is found in some apple orchards. Soils and leaf nutrient levels were generally not well correlated with one another. The only highly significant correlation was be-tween soil P and leaf N. However, positive relations were observed among leaf P and Mn, Fe and Mn, Fe and Zn, and Mn and Zn contents.
Показать больше [+] Меньше [-]A PROPOSED TAXONOMIC SYSTEM OF THE GENUS TRIBULUS L. IN EGYPT BY MEANS OF NUMERICAL TAXONOMY
2005
Kadria Ahmed
Numerical analysis of 62 morphological and histological characters extracted from the 2 previous papers (Ahmed and Mohamed, 2005, a & b) of the 7 studied taxa in the genus Tribulus led to their classification into two groups. The 1st contains 5 pentacyclic flowered taxa (T.terrestris, T. terrestris var. bicornutus, T.macropterus, T.megistopterus & T.mollis) with 2 basal vascular bundles in their small leaflets while the 2nd included 2 tetracyclic flowered taxa (T.kaiseri, T.pentandrus) with single main bundle. The resulted analysis arranged taxa of gp.I into 2 sections while that of gp.II into a third section. Tribulus besides possessing its own generic characters, also shares the Zygophylloid genera in major grounds. Therefore it is recommended to remain in tribe Tribuleae of Zygophylloideae within Zygophyllaceae and never isolated either into a family or even subfamily of its own.
Показать больше [+] Меньше [-]EFFECT OF IRRIGATION WITH SALINIZED WATER ON GROWTH AND CHEMICAL CONSTITUENTS OF “KALA-MATA” OLIVE CULTIVAR GRAFTED ONTO DIFFERENT OLIVE ROOTSTOCKS
2005
Sanaa, Laz
The most important black table olive (Olea europaea L.) “Kalamata” cultivar, grafted onto three different vegetative olive rootstocks[Picual (Pic), Frantoio (Fra) and Koroneiki (Kor) cvs.] was evaluated with 2-year-old grafted plants grown in sand clay soil, and received concentrations of salt mixture (NaCl, Na2So4, CaCl2, MgSo4 and KCl) making 6000 and 8000 ppm with SAR 12 of salinity level, for two seasons. Morphological and chemical parameters were investigated to determine the relative salinity tolerance of these rootstocks and to define possible reasons for any observed differences in the salt tolerance. However, results indicated that differences in response to salinity among rootstocks were observed primarily in morphological traits. Increasing of salinity level in irrigation water decreased, all of scion height and its rate of increase, leaf area, number of leaves/plant and fresh & dry weight of leaves and roots. But different rootstocks can affect the degree to which these pa-rameters is reduced under salinity, where Kalamata growth on Picual and Frantoio was considerably better than on Koroneiki at 6000 and 8000 ppm treatments. In-versely in untreated grafted plants Kalamata on Kornaki exhibited the best growth vigor, comparing with Kal/Pic or Kal/Fra plants, suggesting that a decrease of scion growth in untreated grafted plants is a salt tolerance quality transmitted by tolerant rootstocks. Salinity significantly decreased leaf chlorophyll (a) and (b) content of all grafted plants, but different content among rootstocks were noted. On the contrary, proline content increased in leaves of all treated plants, however, insignificant dif-ference was noted between rootstocks, yet the interaction between the two factors show that Kalamata on Picual and on Frantoio rootstocks recorded higher values of leaf proline content than Kalamata on Koroneiki rootstock. Leaves and roots Na+ and Cl- content of treated grafted plants showed an increment but to a different de-gree, comparing with the untreated (control) plants. There were differences among the grafted plants where Kalamata grafted on Koroneiki (the least tolerant cv.) most-ly affected by saline treatment and accumulated the highest content of Na+ and Cl- in leaves comparing with Kalamata on Picual (the most tolerant cv.) or on Frantoio (the Sanaa LazArab Univ. J. Agric. Sci., 13(2), 2005400moderate tolerant cv.). Tolerant rootstocks contained more Na+ in roots than in leaves. This response become apparent as salinity increased. Leaf N, P and K con-tents decreased in Kalamata leaves as influenced by different rootstocks and increas-ing salinity in irrigation water comparing with the control. Kal/Pic and Kal/Fra plants had higher N% in leaves than Kal/Kor plants, whereas Kal/Pic accumulated K more than the other plants, while P content in leaves of all grafted plants were insig-nificant in the two seasons. Based on the overall growth parameters and chemical composition in response to salinity, Kalamata grafted on Picual exhibited the great-est salt tolerance followed by those grafted on Frantoio whereas, Kalamata on Koro-neiki showed the poorest plants pertaining salt tolerance.
Показать больше [+] Меньше [-]CULTURAL, MORPHOLOGICAL, PHYSIOLOGICAL AND MOLECULAR STUDIES ON SOME STREPTOMYCETE ISOLATES
2005
H Abdel-Fattah
In this study, three isolates of Streptomyces isolated from Egyptian soil at Giza Governorate and belonging to red series were identified based on their cultural, morphological and physiological characters. According to the key proposed by Pridham and Tresner (1974), the experimental isolates ST55, ST71 and ST86 ap-peared to be related to S. lincolnensis, S. venezuelae and S. umbrinus, respectively. In addition, random amplified polymorphic DNA (RAPD)-polymerase chain reac-tion (PCR) was used to amplify the DNA genome of the three applied isolates and an identified strain to determine their fingerprints. This was carried out using 10-decamer oligonucleotides, i.e., OP-A02, OP-D01, OP-D02, OP-D05, OP-D06, OP-D07, OP-D08, OP-D11, OP-D18 and OP-D20. The PCR amplified products were detected by electrophoresing on 1.5% agarose gel and visualized by staining in eth-idium bromide and UV trasilluminator. Results showed that the same oligonucleo-tide flanking fragments differed from one isolate to another with different sizes. Monomorphic and polymorphic fragments were amplified confirming the molecular relationships as well as the genetic diversity between the four applied strains of Streptomyces. Based on the statistical analysis of RAPD-PCR polymorphisms a de-gree of similarities ranged from 33.9 to 59.2 % was found. Furthermore, frag-ment(s), whatever absent or present, were found to be unique molecular markers and could be used for characterization of some isolates. This result supported the idea for using the RAPD-PCR technique for classification of Streptomyces isolates.
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