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MONITORING THE REPRODUCTIVE INDIVIDUALS IN THE ORIENTAL HORNET Vespa orientalis Texto completo
2007
A Elbassiouny
Individuals of the oriental hornet, Vespa orien-talis Fab. were monitored at the apiary of Faculty of Agriculture .Ain Shams University throughout the year of 2006. The individual which was first detected in early spring at the first week of Febru-ary was the mated queens, later during the last week of April workers were appeared. At the first week of September individuals large in size ap-peared which were workers with developed ovary and not a new queen as believed previously. New queens started to appear at the second week of November after about three weeks from appear-ance the drones which appear at the last week of October. The numbers of ovarioles varied from 7 to 8 for each ovary in queens either in spring or in autumn. On the other hand the numbers of ovari-oles were only 7 for each ovary in workers either normal or with developed ovary. The measure-ments of the spermatheca showed no significant differences between all female individuals. The average numbers of spermatozoa in the queen's spermatheca of spring queen hornet were 1.486± 0.370 million spermatozoa and in the new queens who appear in the end of the year, the numbers of spermatozoa recorded 1.343±0.332 million. The counts of spermatozoa in the seminal vesicles of drone hornet recorded 2.336 ± 0.408 million sperms per drone.
Mostrar más [+] Menos [-]EFFECT OF DIFFERENT NITROGEN LEVELS ON PRODUCTIVITY OF THREE MAIZE HYBRIDS FERTIGATION Texto completo
2007
M Hassanein | M Abdrabbo | A Farag
Two field experiments were conducted in 2004 and 2005 seasons at El-Bosaily farm located at Beharia Governorate, Egypt, to study the effect of three nitrogen levels 60, 120 and 180 kg/feddan applied into irrigation water "fertigation" with drip irrigation system on vegetative growth, nutrient content (N, P and K) in leaves and grain and yield of three maize (Zea mays L.) hybrids (Single Cross 10, Three Way Cross 310 and Three Way Cross 324). The experiment design was a split plot with three replications where nitrogen fertilizer levels were distributed in the main plots and maize hybrids allocated in sub plots. The obtained results indicate that the increase of nitrogen level up to 180 kg /fed significantly increased plant height, number of leaves per plant, leaf area index, grain yield and straw weight. Single Cross 10 gave the significant highest vegetative growth and grain yield comparing with the other hybrids. The high-est nitrogen level (180 kg /fed) combined with Single Cross 10 gave the significantly highest grain yield and straw weight. On the other hand, 60 kg N / fed gave the highest nitrogen use effi-ciency (NUE) value followed by 120 kg N / fed The regression analysis of nutrition content (N, P, and K %) between leaf and grain was estimated. The highest regression determination coefficient (r2) was found in nitrogen percentage with r2= 0.965 followed by potassium with r2= 0.936. The lowest r2 was found in phosphorus with r2= 0.872.
Mostrar más [+] Menos [-]EFFECT OF MICROWAVE POWER ON QUALITY PARAMETERS OF PECTIN EXTRACTED FROM MANGO PEEL Texto completo
2007
M Assous | E Abd El-Wahab | K El-Waseif
The present study aims to use microwave pow-er to facilitate the extraction of pectin from dried mango peels, and also to explore the effect of power on some quality parameters of the resultant pectin. Chemical composition of dried mango peels ascertained a high percent of total pectin, being 16.01 % (on dry weight basis). With respect to microwave heating, the optimal experimented power was 600W, and 6 minutes as the best short holding time, which gave 12.80 % yield, 86.54% recovery and 77.20% anhydrogalacturonic acid (AGA) of extracted pectin. Comparing to the commercial pectin, the results of some physico–chemical characterstics of isolated pectin, revealed that the pectin isolated by microwave heating from mango peels, being to some extent analogous to the commercial pectin with respect to its qualities, such as high methoxyl pectin, high degree of estri-fication (DE), and high percent of AGA besides its high viscosity, followed by the pectin isolated using the conventional method. Statistical analysis of organoleptic data showed no significant differ-ences between strawberry jam prepared by using commercial pectin and that treated with pectin isolated by microwave heating as affecting their texture, color, taste and preference. Besides, high significant differences were detected between var-ious concentrations of added pectin, with respect to the texture alone. Generally, the utilization of pectin isolated from mango peels using microwave heating in jam processing gave high quality attrib-utes resembling that of the commercial pectin when added to strawberry jam and this would also lead to gain economical benefits.
Mostrar más [+] Menos [-]MYCOBIOTA OF SOLARIZED AND UNSOLARIZED CUCUMBER SOILS AND ROLE OF SOLARIZATION IN CONTROLLING OF SCLEROTINIA SCLEROTIORUM (LIB.) de BARY UNDER GREENHOUSE CONDITIONS Texto completo
2007
M Ibrahim | A Abdel-Azeem
Soil mycoflora play an important role in agri-cultural economy of a country. The current study was made to have the knowledge about soilborne fungi associated with cucumber crop in solarized and unsolarized soils. Solarization exerted various effects, some of which are biological, others are chemical and still others are physical. All together these changes affected directly or indirectly the mycoflora of the soil, especially the soilborne pathogenic ones. Forty-nine fungal species belong to thirty genera have been isolated from solarized and unsolarized soils. The diversity as well as the count was greatly affected by solarization. By comparison of the species lists of the fungal flora of solarized and unsolarized soils it was evident that soil fungi behave differently toward soil solar-ization, while some new species developed e.g. Absidia, Acrophialophora, Talaromyces, Glio-cladium, some remained unaffected e. g. Aspergil-lus, Penicillium, Chaetomium, Botryotrichum, still others disappeared e. g. Acremonium, Cephali-ophora, Eurotium and others. Regarding solariza-tion for controlling white cucumber rot caused by Sclerotinia sclerotiorum, the obtained data clearly show that solarization had led to a marked in-crease in the number of healthy plants up to 72.5%.
Mostrar más [+] Menos [-]A PRELIMINARY SURVEY OF THE HOVERFLIES INSECTS (SYRPHIDAE, DIPTERA) IN DEIR-EZZOR, EASTERN SYRIA FAUNISTICS STUDY Texto completo
2007
M Idraw
The hoverflies insect species are considered the most economic pollinators of various flowers, the adult visitors feed on nectar and pollen. Many of syrphid survivors are voracious aphid feeders in their larval instars and are considered greatest bio-control agent. They are beneficial insects when estimating the damage of pest control is consid-ered. In spite of their great economic importance, no progress has been estimated on taxonomy and biology of these insects in Syria. A surveillance studies of such flies were carried out in three loca-tions (Agroecosystems) in Deir-Ezzor, Eastern Syria during March-July 2006, based on number of captured adults. Yellow dish traps were used, and 12 spieces were identified and counted. This study will be an applicable addition to the availa-ble knowledge about the Syrian fauna.
Mostrar más [+] Menos [-]EFFECT OF CROP ROTATIONS AND NITROGEN FERTILIZATION ON YIELD, YIELD COMPONENTS AND ASSOCIATED WEEDS IN COTTON Texto completo
2007
S Toaima
This study was conducted at Sids Experimental Research Station, Beni Suief Governorate, starting from year 2000 to study the effect of rotation dura-tion (every year, 2- year rotation and 3- year rota-tion) and nitrogen fertilizer rates; 45, 60 and 75 kg N/ fed on growth, yield components and yield of cotton, as well as associated weeds. A split plot design was used with four replicates. The data indicated that crop rotation had significant effect on plant height, number of fruiting branches/ plant, number of open bolls, seed cotton yield/ plant and seed cotton yield/ fed. Seed cotton yield/ fed was increased by 10.99 and 23.62 % when 2-year and 3-year rotations were applied, compared to 1-year rotation (average of both seasons). In-creasing N- fertilization up to 60 kg N/ fed caused significant increases in all studied traits. The best estimate of yield (Y) plotted against N rate (X) for annually rotated cotton was the linear equation of Y =2.44 + 0.074x (R2 =0.81). Two years rotation showed a quadratic association with increasing the N rate, R2 = 0.86 and 0.88, respectively. The high-est values of total fresh weeds were 2.85 and 2.60 kg/ m2 (broad and grassy weeds) when 1-year ro-tation was applied, while the lowest values were 1.50 and 1.35 kg/ m2 when 3-year rotation was applied in the first and second season, respective-ly.
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