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SOME ECOLOGICAL ASPECTS OF TWO WHITEFLY SPECIES INFESTING ARABIAN JASMINE SHRUBS IN EGYPT (HEMIPTERA: STERNORRHYNCHA: ALEYRODI Texte intégral
2005
A. Helmi,
Two whitefly species, Aleurotuberculatus jasmini Takahashi and Dialeurodes kirkaldyi (Kotinsky) were found infesting Arabian jasmine shrubs, Jasminium sambac at the Botanic Garden of Faculty of Agriculture, Ain Shams University, Shoubra, Qalyubiya, Egypt. To obtain basic ecological data for both species, samples of Arabian jasmine leaves were conducted every ten-day intervals throughout one complete year (January to December 2004). Seasonal fluctuations of alive total population, nymphs and adults (empty exuviae) of the both species indicated that the D. kirkaldyi was more dominant one than A. jasmini throughout the tested year. Three periods of seasonal abundance for both species were established. Three annual field generations were estimated for D. kirkaldyi, which lasted 170, 90 and 100 days, respectively. While A. jasmini passed throughout five annual field generations, which lasted 80, 80, 70, 60 and 70 days, respectively. The effects of nine ecological factors (7 physical +2 biotic) on the population dynamics of alive nymphs population for both species were estimated. Each factor gave variable effects for both species while the combined effects of these nine factors were responsible as a group for about 74.2% and 95.5% of the changes in nymphal population densities of D. kirkaldyi and A. jasmini, respectively.
Afficher plus [+] Moins [-]GC-MASS ANALYSIS OF BITTER ORANGE PETITGRAIN BIGARADE OIL PRODUCED IN EGYPT AND STORED UNDER DIFFERENT TEMPERATURES Texte intégral
2005
A Abd El-Rashid,
Identification of bitter orange petitgrain bigarade oil produced in Egypt was studied by GC/MS on carbowax – 20M colum. It was found that linalyl acetate, which represented more than 25% of the whole oil was considered to be the major component of ester fraction; while linalool, which ranged from (30-33.7%) was the main alcohol components. On the other hand, limonene, (E)-β-ocimene,myrcene and β-pinene were the highest monoterpene hydrocarbons. Room temperature (about 20°C), 4 and -18°C were used for storing the samples for 6 mounths. No pronounced effect was noticed on the composition of petitgrain oil with the exception of slight effect on the color, acid number and solubility (v/v 70% alcohol) when samples stored at 20°C. Statistical analyses proved that 4 ºC could be considered the best fit temperature at which no significant changes occur in both the major chemical analyses and the main identified volatile constituents.
Afficher plus [+] Moins [-]EFFICIENCY OF CERTAIN INSECTICIDES ON WHITEFLY LEAF CURL VIRUS AND THEIR RESIDUES IN TOMATO FRUITS Texte intégral
2005
Ibrahim Soad, A. | Elias Nadra, M. | M.Y Ola, | El-Adl Fathy E. | El-Sheemy M.KH.
The work was conducted to clarify the efficiency of certain insecticides on the population of whitefly B. tabaci and incidence of yellow leaf curl virus (TYLCV) in tomato field. The experiment was carried out during Nili plantation of two successive seasons at El-Fayoum governorate. The obtained data showed that the alternate use of etofenprox /thiamethoxam; imidacloprid/ thiamethoxam; acetamiprid/ etofenprox; single continuous application of etofenprox; etofenprox / imidacloprid; acetamiprid/ imidacloprid; thiamethoxam/ acetamiprid; imidacloprid; thiamethoxam and acetamiprid gave excellent initial mortality over 90% on the adult stage of B. tabaci and incidence of tomato yellow leaf curl virus without significant differences between treatments. Thimethoxam as soil drench proved to be the most effective insecticide against adult and immature stages of whitefly, while acetamiprid achieved the lowest mortality for these two stages as well as short residual mortality. On the other hand, alternation of etofenprox / imidacloprid showed the highest initial mortality on nymphs. Residue levels in tomato fruits were also investigated at 30, 45 and 60 days after application of tested insecticides. For imidacloprid residues were found in amounts nearly above maximum residue levels MRLs 30 days while degraded to amounts below MRL by the progression of time to 45 and 60 days after application. Application of imidacloprid in alternate spray program with thiamethoxam; etofenprox; acetamiprid resulted in residues below MRL at the 3 preharvest intervals. Acetamiprid when used at the recommended rate showed the residue of 0.36 mg/kg at early season and then decreased to 0.08 mg/kg at late season. Alternate use of acetamiprid with thiamethoxam; etofenprox or imidacloprid reduce MRLs in tomato fruits. The successive applications of etofenprox alone at the recommended rate resulted in residues above MRL after 30 and 45 days and approximately near MRL at 60 days. On the other hand, the half rate in alternative use with imidacloprid; acetamiprid or thiamethoxam showed residues below MRL at all sampling intervals. Thiamethoxam when used in single successive applications gave residues of 2.5, 1.9 and 1.5 mg/kg at the 3 preharvest intervals, respectively
Afficher plus [+] Moins [-]HETEROSIS AND COMBINING ABILITY FOR FIBER-TO-SEED ATTACHMENT FORCE, EARLINESS, YIELD AND YIELD COMPONENTS IN A HALF DIALLEL CROSS OF COTTON Texte intégral
2005
M. Hassan Rokaya, | El-Marakby A.M. | El-Agroudy M.H. | Seif M.G.
Seven cotton genotypes involving cvs. Giza 70, Giza, 77, Giza 86 and Giza 83 and the exotic varieties; Pima S7 and SeaIsland, as well as, the American Upland variety Tamcot C.E., were crossed in a diallel pattern, excluding reciprocals, in 2000 season to produce 21 F1 hybrids. Parents and F1'swere evaluated in 2001 season for eight economic traits. Mean squares due to genotypes were highly significant for all traits, revealing the presence of sufficient variability in the population. Significant desired negative mid and better parent heterosis were found for fiber-to-seed attachment force and days to flowering. Significant positive heterosis was also observed for yield and its components. The variances due to general combining ability (GCA) and specific combining ability, (SCA) were significant for all studied traits, indicating the importance of both additive and non additive gene action in the inheritance of these characters. The GCA/SCA ratio was found to be greater than unity, indicating predominance of additive and additive x additive types of gene action in the inheritance of these traits. Based on GCA effects, the Upland variety Tamcot C.E. proved to be the best general combiner for earliness, boll weight, seed index, seed cotton yield and lint cotton yield/ plant. Giza 83 seemed to be good combiner for fiber-to-seed attachment force, Giza 86 for lint percentage and Pima S7 for number of bolls per plant.
Afficher plus [+] Moins [-]FORTIFICATION OF PROCESSED CHEESE SPREAD WITH ACCUSTOMED EDIBLE MUSHROOM Texte intégral
2005
A. Fathi Fatma | A.M. Hussein Gehan | Mohamed A.G.
The effect of incorporating accustomed edible mushroom (Agaricus campestris) into processed cheese spread (PCSs) on the chemical, microbiological and organoleptic properties was evaluated. Tiny pieces of mushroom accustomed with steeping into citric acid and boiling in emulsifying salt solution were added to the blend of the cheese spread base at the levels of 5,10 and 15 %. The resulting PCSs were stored at 7°C for 3 months. Significant differences (p < 0.05) were recorded among the chemical composition of PCSs made without and with addition of mushroom. The incorporation of mushroom into PCSs resulted in higher contents of total solids, total protein, SN, ash, total carbohydrates and fiber, as well as pH values than the control spread. On the other hand, control treatment made without mushroom possessed the highest content in F/DM. Addition of mushroom to the base blend did not significantly affect (p > 0.05) in the salt and TVFA contents. The standard plate and psychrotrophic counts of PCSs made without and with mushroom showed slight differences when fresh and during the storage period. The standard plate counts slightly increased during the storage period reaching the maximum counts after one month, and then decreased with prolonged storage. Psychrotrophic bacteria gradually increased in all treatments throughout the storage period. On the other hand, no colonies were found from yeasts and molds, coliform and mesophilic anaerobic spores in all samples examined. Obvious differences (p < 0.05) were noticed in the organoleptic evaluation scores among all treatments of PCSs. The flavours of PCSs with mushroom were generally better and preferable when fresh and throughout the storage period. Addition of 15 % mushroom caused an over pieces of mushroom, which defected the body & texture and appearance & colour of the resulting spread. Therefore, PCSs with improved nutritional and functional values as well as acceptable organoleptic properties and good microbiological quality could be made by incorporation of accustomed edible mushroom into the base blend at the levels of 5 and 10% with refrigerated expiry period more than 3 months.
Afficher plus [+] Moins [-]INDUCTION OF DEFENSE RESPONSES IN TOMATO PLANTS INOCULATED WITH PHYTOSTIMULATION MICROORGANISMS AGAINST Fusarium oxysporum Texte intégral
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.
Afficher plus [+] Moins [-]MITES IN MARJORAM AND CHAMOMILE CULTIVATIONS IN FAYOUM AND THE RELATIVE ABUNDANCE OF TWENTY SIX SPECIES Texte intégral
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.
Afficher plus [+] Moins [-]EFFECT OF SALINITY AND NITROGEN BIO-FERTILIZATION ON SOME SUDAN GRASS (SORGHUM SUDANENSE (L.) MOENCH) VARIETIES AT RAS SUDR Texte intégral
2005
S.M Abd El-Rahman, | El Shouny S.M.; K.A. | Abd El-Gawad M.A. Ashoub; M.A. | Abd El-Maaboud M.Sh.
This study was carried out at Ras Sudr Experimental Station, South Sinai during 2001 and 2002 seasons. Four sudan grass varieties (Giza2, Piper, Hybrid102 and Is3214) were tested under five nitrogen fertilizer (Mineral and biofertilizer) treatments under two levels of irrigation water salinity (3700 and 9200 ppm). Growth characters i.e. plant height, number of tillers/plant, stem diameter, number of leaves/plant, leaf area, leaves/stem ratio, and forage yield (fresh and dry weight of stem+sheaths and fresh and dry weight of forage yield) were recorded. In addition, carbohydrates, protein, fibers and ash percentages (in leaves and stems) and proline in leaves were determined. Results demonstrate that the Piper variety had the highest value of forage yield compared with the other varieties. The recommended dose of mineral nitrogen fertilizer gave the highest values followed by mixture of biofertilizers (Azospirillum plus Azotobacter) under the two salinity levels of irrigation water at both cuts (the first one was harvested after 65 days from sowing date and the second was obtained at the same time interval). Moreover there was a significant decrease in all growth characteristics and the yield of four sudan grass varieties by increasing the level of irrigation water salinity from 3700 to 9200 ppm except proline in leaves which significantly increased by increasing the level of salinity
Afficher plus [+] Moins [-]TOXICOLOGICAL AND BIOCHEMICAL EFFECTS OF BIO-AGENT PRODUCTS ON THE COTTON LEAF WORM, SPODOPTERA littoralis (BOISD.) (LEPIDOPTERA: NOCTUIDAE) Texte intégral
2005
H.E.A. Sakr Hanafy, H.E.M. | El-Sayed W.
A comparison on the larvicidial activity of four commercial bacterial and viral bioagents, Profect®, Virotecto®, Viroset® and Protecto® were evaluated on the 2nd and 4th larval instars of Spodoptera littoralis (Biosd.). The LC50 values showed 1.35, 1.52, 1.57 and 1.61 mg/ ml against 2nd instar larvae, respectively. On the other hand, the LC50 values recorded 2.03, 2.5, 2.72 and 3.01 mg/L. on 4th instar larvae of S. littoralis using the above mentioned commercial bioagent products, respectively. The effect on four isozymes, i.e., , esterase (EST), glutamate oxaloacetate transaminase (GOT), malate dehydrogenase (MDH) and alcohol dehydrogenase (ADH) were evaluated. The obtained results indicated differences in the activity of the isozymes in treated 4th instar larvae as compared to untreated larvae.
Afficher plus [+] Moins [-]A TAXONOMIC STUDY OF THE GENUS TRIBULUS L. IN EGYPT I- MORPHOLOGICAL FEATURES Texte intégral
2005
Kadria Ahmed | Amaal Mohamed
This work aims at classifying the genus Tribulus which is represented in Egypt by 7 taxa (6 species & one variety) viz.: Tribulus terrestris, T.terrestris var. bicornu-tus, T.pentandrus, T.macropterus, T.megistopterus, T.mollis and T.kaiseri according to the current classical morphological features including those of flower which can lead to a correct taxonomic decision. The work includes detailed comparative vege-tative and reproductive morphology of the studied taxa, while drawings representing the extracted results are tried into cumulative plates. Also an artificial indented di-chotomous key for the studied taxa is constructed. The key easily differentiated the pentacyclic flowered taxa from the tetracyclic in 2 separated collections. The 1st is composed of 5 taxa in which; nature of pericarp (bony or herbaceous), leaflet pairs into large leaf (7 or 6), calyx (persistant or deciduous), anther connection (basi-or dorsifixed) and others are found effective in identification. On the other hand; calyx imbrication (quincuncial or ascending) and stigma (persistant or deciduous) are used in separating the 2 spp. within the 2nd collection.
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