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SOME ECOLOGICAL ASPECTS OF TWO WHITEFLY SPECIES INFESTING ARABIAN JASMINE SHRUBS IN EGYPT (HEMIPTERA: STERNORRHYNCHA: ALEYRODI
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 [-]ISOLATION, PURIFICATION AND IDENTIFICATION OF SOME MICROORGANISMS PRODUCE PLANT GROWTH PROMOTING SUBSTANCES (METHYLOTROPHIC BACTERIA)
2005
Orf, O.M. Heba | Eweda Wedad, E.E. | Shehata Sawsan, F. | Abo-Taleb H.H.
Recently, the potential economical importance of the methylotrophic bacteria encouraged the isolation of this group. In the present study five Egyptian isolates were obtained from green leaves surface of legume plants named PPFM.C (ChickPea), PPFM.Ph (Common bean), PPFM.F (Faba bean), PPFM.P (Peanut) and PPFM.S (Soybean) ,to study their general characters which belonging to methylotrophic bacteria. Morphological studies indicate that all isolates were short rods, gram negative and motile. All Physiological studies to the isolates gave the same results except PPFM.F which could not grow in peptone medium. All isolates were sensitive to Kanamycin but they were resistant to Erythromycin. There was a great range in the ability of the isolates to grow on different sodium chloride concentrations indicating that PPFM.Ph grew well in 5 % sodium chloride, and they were able to excrete and produce cytokinin. Molecular biology studies indicated that there was a great similarity between PPFM.C and PPFM.Ph (99.34%). Identification was carried out to the5 isolates, PPFM.F may be related to Methylobacterium mesophilicum, PPFM.P may be related to M. fujisawaense and PPFM.Ph, PPFM.C and PPFM.S were related to M. radiotolerans.
Afficher plus [+] Moins [-]A COMPARATIVE STUDY ON FRUIT QUALITY PARAMETERS AND YIELD OF FOUR OLIVE CULTIVARS GROWN IN SANDY SOIL
2005
O.A. Nofal Rezk, A.I.; | El-Masri M.F.
Four olive cultivars namely Manzanello, Picual, Coratina and Arbicon grown at Wadi El-Natroon area, Egypt under drip irrigation system in sandy soil were compared for optimizing their own yield as well as fruit quality parameters during 2001 (off-year) and 2002 (on-year), by application of an integrated and balanced fertigaion program including macro and micro-nutrients. Results showed that remarkable and significant differences in leaf mineral contents, yield and yield quality parameters were detected by using well distributed fertilizer program during the growing season of olive trees. The treated four cultivars attained higher yield in the “on” and “off” year than the control. The most outstanding olive cultivars having greater yield were Picual, Manzanello, Coratina and Arbicon in a descending order. Oil percentage was maximized with Picual olive while, Arbicon olive had the lowest value. Free fatty acids (%), Iodine number as well as Acidity (%) were minimized in Coratina olive and the lowest peroxide number as was in Picual olive. It is apparent that for planting Picual olive variety proved to be the promising one due to its greatest yield and best fruit quality specially when the actual requirements of macro and micro nutrients were used through the drip irrigation system.
Afficher plus [+] Moins [-]EFFECT OF THE NATURE OF THE FEEDING RESOURCE ON ITS IN VITRO GAS PRODUCTION KINETICS USING RUMEN FLUID OF SLAUGHTERED DROMEDARY
2005
Dehimi; Y. Dib Arhab, R.; A. | Bousseboua H. Bousseboua
Degradation aspects in terms of kinetics of the tested samples namely dates, oranges and olive residues by the dromedary ruminal microflora is comparatively studied with vetch-oat hay as a standard. The results indicate greater hydrolytic ac-tivity of the dromedary ruminal microflora towards dates and orange residues than both olive residues and hay. Fermentation of dates and orange residues reaches their stationary phase after 24 hours and olive wastes after 48 hours. However, fermentation process was marked by two phase; namely the degradation of soluble fraction and that of cellulosic one. The results showed also that types of substrate is a determining factor for in vitro gas production. In fact, substrate rich in cellular content (dates and orange residues) is characterised by a fast fermentation that moves towards CO2 production, and it is marked by a long latency phase. On contrary, the fibrous substrate degradation (olive residues and hay) is tributary of less long latency period and generates CH4. The degradation level observed indicates that the dates and oranges residues might represent an acceptable source of energy for dromedary. On the other hand, the olive residues, in spite of being rich in organic matter, cannot be used in animal feeding.
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
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 [-]INTERACTIVE EFFECTS OF ZINC AND DIFFERENT NITROGEN SOURCES ON YIELD AND QUALITY OF ONION
2005
A.M.R. Abdel-Mawgoud, | Abou-Hussein S.D. | Salman S.R. | El-Nemr M.A.
and 2003 to investigate the interactive effect of Zn and different nitrogen sources, i.e., mineral nitrogen (ammonium sulfate) and organic nitrogen (poultry manure) on the growth and productivity of onion (Allium cepa) cv. Giza 20. Four levels of Zn application (0, 1, 2 and 3 ppm) in a sulfate form were foliar sprayed at 30 and 60 days after planting. Within each Zn application, three treatments of nitrogen dose were applied in different combination forms (mineral and organic sources). Nitrogen treatments were 100% mineral N; 75% mineral + 25% organic and 50% mineral + 50% organic. Organic-N source was poultry manure. All poultry manure treatments were applied during soil preparation. Data showed that all growth parameters of onion plants increased as the fraction of poultry manure increased. Zn had also a positive effect on all plant parameters except of plant length, and leaf dry weight. The interactive effect of Zn and poultry manure increased yield and quality of onion bulbs. The most effective treatments on bulb fresh weight, total yield and quality were the spraying with 1 or 2 ppm zinc and the application of N as 75% mineral and 25% organic, in both seasons
Afficher plus [+] Moins [-]DISSIPATION OF MALATHION IN DILL AND CORIANDER PLANTS AND THEIR OILS
2005
Abd El-Rahman Mohamed M.T. | Zaki MayssounY. | Hamouda Laila S.
The insecticide malathion (57% E.C.) was applied at the rate of 712.5 gm active ingredient per feddan on dill, Anethum graveolens L. and coriander, Corianderum sativum L. for controlling aphids infesting these plants. An analytical method, using gas chromatography equipped with flame photometric detector was used for detecting the insecticide residues. A field trial was conducted to determine the rate of dissipation of malathion in dill and coriander plants and in the resulting oil. Residue analysis showed that the initial deposits determined one hour after application were 35.81 & 22.7 ppm in dill and coriander plants, respectively. Rates of dissipation of malathion were 4.72, 51.1, 68.39, 88.41 and 93.49% in dill plants and were 13.61, 43.22, 66.78, 86.26 and 91.85% in coriander plants at 1, 3, 7, 14 and 21 days post treatment, respectively. The pesticide was decayed quite rapidly in and on dill and coriander plants and detectable residues (1.62 and 0.93 ppm) were observed in these plants 28 days after treatment. At harvest 46 days for coriander and 70 days for dill after application malathion was found at average levels of 0.78 mg/kg and 0.54 mg/kg in dill and coriander dry seed, respectively. The volatile oil extracted from the seed by steam distillation process was contaminated with the insecticide at a higher levels than in the seed [about sevenfold in dill oil, 5.21 mg/kg and ninteenfold in coriander oil 10.16 mg/kg]. This means that malathion had tendency to co-distill with the dill and coriander oil throughout steam distillation process.
Afficher plus [+] Moins [-]TOXICOLOGICAL AND BIOCHEMICAL EFFECTS OF BIO-AGENT PRODUCTS ON THE COTTON LEAF WORM, SPODOPTERA littoralis (BOISD.) (LEPIDOPTERA: NOCTUIDAE)
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 [-]ANTIOXIDANT ACTIVITY OF SOME SAGE LEAVE EXTRACTS
2005
A. F. | Al-Saadi A.H. | Al-Saadi M.H. | Hamad Wessal H.
Sage leaves were successively extracted with water, chloroform: methanol (2:1, v/v), n- hexane, benzene, diethyl ether, chloroform, chloroform: methanol (8:2, v/v) and dichloromethan. Antioxidant activities were detected using two methods :1. The carotene spray method and 2.Measuring the coupled oxidation of β–carotene and linoleic acid. Generally, all extracts had antioxidant activities when tested by the first method. By means of the second method, the extracts of water, diethyl ether and chloroform : methanol( 8:2, v/v ) showed the greatest antixidant activities , followed by the extracts of organic and aqueous phases ( which were extracted with chloroform: methanol, 2:1, v/v), dichloromethan and chloroform, while the n- hexane and benzene extracts showed low activities.
Afficher plus [+] Moins [-]IN VITRO PROPAGATION OF THREE ALMOND CULTIVARS AND THE ALMOND – PEACH HYBRID ROOT-STOCK“HANSEN”
2005
A El-Hammady | Wafaa Wanas | A Abd El-Hamid | M El-Salem
Stem node explants of three almond (Prunus dulcis Mill) cultivars (Om – Elfahm, M-Dalt and Ne Plus Ultra) and the hybrid rootstock “Hansen” cv. were suc-cessfully established and proliferated on Murashige and Skoog medium (MS) sup-plemented with benzyl adenine (BA) at 0.0 - 2.0 mgl -1 and indol butyric acid (IBA) at 0.0 - 0.1 mgl-1 .The highest bud development percentage of stem node explant was obtained with medium contained BA at 2 mgl-1 with or without IBA at 0.1 mgl-1 for M – Dalet and Ne Plus Ultra almond cultivars compared with other treatments. The longest shoot during establishment stage was recorded by “Hansen” rootstock cultured in MS with BA at 2.0 mgl-1 plus IBA at 0.01 mgl-1.Using BA at 1.0 mgl-1 plus IBA at 0.1 mgl-1 and BA at 2.0 mgl -1 plus 0.05 or 0.1 mgl -1gave the highest number of proliferated shoots for Om – Elfahm, M-Dalt and Ne Puls Ultra cvs. and “Hansen”, respectively in the 3rd subculture. The best average proliferated shoot length was achieved with medium supplemented with BA at 1.0 mgl-1 plus IBA at 0.05 mgl-1 or 0.1 mgl-1 for M-Dalt, Ne Puls Ultra and “Hansen” respectively, where-as, using BA at 2.0 mgl -1 plus IBA at 0.1 mgl -1 recorded the longest average prolif-erated shoot for Om- Elfahm cultivar. Microshoots were rooted in modified Bourgin and Nitsch medium supplemented with IBA or NAA at 1.0 mgl-1 only or combination (0.2 IBA mgl-1 + NAA 0.4 mgl-1, IBA 0.4 mgl-1 + NAA 0.8 mgl-1 and IBA 0.5 mgl-1 + NAA 1.0 mgl-1). The large callus (more than 10 mm diameter) was recorded with “Hansen” rootstock and Om – Elfahm treated by IBA at 0.4 mgl -1 plus NAA at 0.8 mgl -1. The greatest rooting percentage (66.67%) was obtained with medium contained IBA at 0.2 or 0.4 mgl-1 plus NAA at 0.4 or 0.8 mgl-1 for “Hansen” rootstock and Ne Plus Ultra shoots.
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