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Resultados 1151-1160 de 1,442
UNTRADITIONAL METHODS OF P-APPLICATION FOR RAISING ITS EFFICIENCY ON SANDY SOIL
2005
K Nassar | M El-Shouny | S El-Fiki
Soils of Egypt characterize with raising pH values, CaCO3 content, clay and Fe & Al oxides. These factors contribute, to a large extent, in P-fixation in soil and its transformation into unavailable forms. This reflect, in turn, on plant growth and the resultant crop. So, the main target of this investigation is raising the use efficiency of P-fertilization, decreasing P-fixation, increasing its availability in soil and promoting its uptake by plant through testing new methods for P-application compared with the traditional one (P-application before sowing). Therefore, two field experiments were designed in sandy soils during the two winter seasons 2002/2003 and 2003/2004 at South Tahrir Res. Station, Ali Moubark village, El-Bustan region, Behira gover-norate under drip irrigation system. For the two experiments, P was applied as soil or seed coating. Soil application treatments were added at a rate of 30 kg P2O5/fed., once before sowing, twice: before sowing and during the vegetative growth stages or in three portions, before sowing and during the vegetative and flowering growth stages. In seed coating method, seed were coated before sowing with P at rates of 0.1, 0.2 and 0.3 kg P2O5/kg seed. Data obtained revealed that the treatments of P-soil application generally surpassed the P-seed coating ones. In this respect, P-soil appli-cation in three portions (at sowing and during the vegetative and flowering growth stages) gave the highest increments in seed, straw and seed protein yields as well as macro- and micronutrients contents in both seed and straw compared with the tradi-tional method of soil P-application. Moreover, seed coated with 0.2 kg P2O5/kg seeds attained the highest increases in all abovementioned yield components and nu-tritive contents among the treatments of seed coating method, whereas, coating of seeds with 0.3 kg P2O5/kg seeds caused the least ones. Therefore, it can be conclud-ed that the addition of P to sandy soil at a rate of 30 kg P2O5/fed., in three portions, i.e. at sowing and during the vegetative and flowering growth stages reduce P-fixation by soil factors, increase its availability, promote its uptake by plant, achieve the highest productivity of faba bean seed, straw and seed protein yields and im-prove the nutritive contents of both seeds and straw.
Mostrar más [+] Menos [-]AGGEZI AND KORONEIKI OLIVE TREES AS AFFECTED BY ORGANIC AND BIO – FERTILIZERS, CALCIUM CITRATE AND POTASSEINE
2005
A Abou El-Khashab | Safia A. Taleb | Wafaa Saeed
The present study was carried out in an olive orchard at 6th of October city, Giza Governorate, Egypt during 2002 and 2003 growing seasons on “Aggezi” and “Koroneiki” olive cultivars for table and oil purposes, respectively. The objective of this study was to investigate the effect of organic farmyard manure (FYM), compost (COM) manure and biofertilizers (Bio) as the combination between phosphorene and nitrobeine, calcium citrate (Cac) and potasseine (K). Besides, the fertilization program adopted in the farm [N (750g/tree), P2O5 (600g/tree) & K2O (500g/tree)] was used as control. The results revealed that, the application of different aforemen-tioned treatments increased significantly shoot growth (length and diameter, number of leaves shoot and area/leaf) compared to the control in both cultivars (Aggezi and Koroneiki) during the two growing seasons. In this concern, the application of FYM+Cac influenced significantly shoot length & diameter, number of leaves/shoot and area/leaf of Koroneiki cv. and shoot diameter of Aggezi cv. Meantime the area /leaf of both cvs.increased when fertilized by FYM+COM+Cac. Whereas, the com-bination of FYM, COM, Cac, Bio, and K improved significantly blooming charac-teristics (number of flowers/inflorescence, inflorescence length and perfect flowers %) of Aggezi and Koroneiki olive cvs. However, number of fruits/shoot and yield of both cultivars increased significantly when treated by the combination of organic and biofertilizers, especially FYM+COM+Bio. Moreover, pulp/seed ratio was in-creased when treated with FYM+Bio (especially in 1st season). In addition, Koro-neiki cv. when provided with FYM+COM+Bio treatment produced the richest fruits in their oil content. Aggezi cv. trees when fertilized with the combination of organic manure & calcium, gave higher contents of chlorophyll (A), (B) & total chlorophyll, however, in Koroneiki cv. chlorophyll B didn't affect. Eventually, nutrient elements (NPK) contents didn't take a definite trend except for N which was affected signifi-cantly with the different combinations, while P & K in Aggezi leaves were influ-enced by FYM only. On the other hand, Koroneiki trees treated with COM+Bio had the highest leaf N content. Leaf P content was positively affected by FYM+Cac in 2002 and FYM+COM+Bio in 2003. Meantime, FYM+K followed by COM+Bio in-duced the highest stimulative effect on leaf K content.
Mostrar más [+] Menos [-]THE INFLUENCE OF STEM CUTTING LENGTH AND IBA TREATMENTS ON PROPAGATION OF NATIVE SAUDI ARABIAN GRAPEVINE
2005
B Hamooh
The Saudi Arabian Ministry of Agriculture experimental station at Al-Maddina Al-Monwarah region, identified very few plantations of the most productive Vitis vinifera var. maddini with the highest fruit quality. This research was designed to optimize rooting effeciency in relation to cutting length and auxin treatment. Cutting length (long vs short) showed strong impact on rooting ability. Results showed that longer cuttings produce more and longer roots than shorter ones. IBA treatments up to the 500 ppm level showed significant increase in root number, but do not have significant impact on root length. Rooted cuttings were planted in an open field for further evaluations. These findings may facilitate the clonal propagation of this val-uable vines at Al-Maddina Al-Monwarah region, grapevine growers and Horticultur-ists in Saudi Arabia .
Mostrar más [+] Menos [-]EFFECT OF IN VITRO PRESERVATION ON THE RAPD PROFILES IN "KORONAIKI" AND "KALAMATA" OLIVE CULTIVARS (OLEA europaea L.)
2005
Wafaa Saeed | H Hassan | Saffia Gazy | Eglal Shaban
The present work aimed to establish a protocol to minimize the potential effect of in-vitro preservation for 8 months of the two olive cultivars i.e Koronaiki and Kalamata. Three culture conditions (treatments) were chosen to investigate the most suitable one for minimizing somaclonal variations after the process of in vitro preservation. The conditions include MS medium plus mannitol, MS medium plus low temperature and MS medium plus naphthaline acetic acid. RAPD-based finger-printing was employed to determine the effects of the different chemical constituents and other culture conditions on the extent of somaclonal variations after 8 months of in vitro preservation at the DNA level. Four arbitrary primers (OPA-04, -07, -14 and -16) were successfully utilized to achieve such goal. The obtained results showed that Mannitol has more pronounced effect than the other investigated preservation culture and conditions for decreasing DNA alterations.
Mostrar más [+] Menos [-]A TAXONOMIC STUDY OF THE GENUS TRIBULUS L. IN EGYPT II- HISTOLOGICAL FEATURES
2005
Kadria Ahmed | Amaal Mohamed
Comparative detailed vegetative anatomical investigation for stems, leaves and foliar details of the 7 studied taxa of the genus Tribulus in Egypt has been carried out in order to its reclassification based on internal structures. Accurate drawings for each of the studied organs are outlined into cumulative plates. Also an artificial in-dented dichotomous key has been constructed. Variation in number of basal vascular bundles (2 or 1) into the small leaflet-blade within the large leaf is utilized in classi-fying the studied taxa into two Groups. The 1st contained 5 taxa with 2 main bundles while the 2nd included 2 taxa each with single and unique basal bundle/small leaflet. Members of Gp.I are distinguished according to differences in : phloem & cambium characters, presence of 2 distinct glandular trichome types, stem outline & vascular cylinder contents, no. of petiolar vascular strands from base to apex, type of cuticle, type of pericyclic sclerenchymatous patches and others. On the other hand, variation in nature of starch sheath cells (from storing crystals to empty) and presence or ab-sence of schizogenous carnals in pith are found diagnostic in separating both mem-bers in Gp. II.
Mostrar más [+] Menos [-]NATURAL ENEMIES ASSOCIATED WITH MEALY PLUM APHID HYALOPTERUS PRUNI (Geoff.), (HOMOPTERA: APHIDIDAE) INFESTED APRICOT TREES, AT QALUBIA GOVERNORATE
2005
H Abul-Fadl | M El-Khawas | Salwa Abdel- Samad
The present work was carried out to study the population dynamics of the mealy plum aphid Hyalopterus pruni (Geoff.) and related parasitoids and predators on apricot trees, during the two successive seasons, 2003 and 2004, at Qalubia Gover-norate. The obtained data revealed that, the occurrence of H. pruni on apricot trees covered 5 months (from February to June). The mean total numbers of this aphid species per season were 1.78 (0.01-6.37) and 2.83 (0.00-10.01) individuals./leaf. The maximum numbers of H. pruni were recorded during the 2nd weeks of April, 2003 and 2004. No aphid individuals were observed during the period extended from July to September, in the two studied seasons. Four species of parasitoids; namely Aphidius matricariae Hal., Lysiphylbus sp. (1ry parasitoids) and 2 species of Alloxysta spp. (2ry parasitoids) were recorded during this study, attacking H. pruni. These parasitoid species were found during nearly three months of each season, in connection with the population density of the previous aphid species. The first para-sitoid was the highest in its numbers. The total numbers of predatory species per season were 407 and 1082 individuals, in the two studied seasons, 2003 and 2004, respectively. The maximum monthly occurrence of these predatory species was dur-ing April, 2003 (146 individuals) and April, 2004 (581 individuals), respectively. The predator Chrysoperla septempunctata L. had the highest percentages of occur-rence among other recorded predatory species (52.83 and 73.01%, respectively). In general, the parasitoid A. matricariae and the predator C. septempunctata, could be mass reared and released for controlling H. pruni on apricot trees with other availa-ble safe control methods developed in Integrated Pest Management (IPM) programs against this pest.
Mostrar más [+] Menos [-]OCCURANCE OF LAYING WORKERS AT DIFFERENT HONEY BEE COLONIES STATUS
2005
A Elbassiouny
Laying workers expressed as Workers with Activate Ovaries (WAO) having ma-ture oocytes had been studied in colonies headed with natural mated carnica queens. The results showed that the WAO were affected by the age of the queen, where it reached 0.8, 1.3 and 2.2 % for colonies headed with queens 10, 20 and 30 month old, respectively. The worker ovaries started to activate when the reached 22. 18 and 12 days from emergence for colonies headed with caged mated queens, caged virgin queens and queenless colonies, respectively. Also, when the worker's age reached 30 days, the percentages of WAO occurrence reached 3.3, 7.3 and 14.7 % for the corre-sponding colonies status, respectively. In preparing swarm boxes, when the bee-keepers failed to introduce the queens into the nuclei until two days, one week and two weeks, the WAO recorded 1.4, 4.8 and 9.2 %, respectively. In case of queen rearing, the presence of WAO was not significant until the fifth day, and then in-creased gradually to reach an average of 4.6% in the tenth day.
Mostrar más [+] Menos [-]GROWTH AND PRODUCTIVITY OF WHEAT PLANTS AS AFFECTED BY COMPLETE FOLIAR FERTILIZER COMPOUNDS UNDER WATER STRESS CONDITIONS IN NEWLY CULTIVATED SANDY LAND
2005
Ahmed A | M Ahmed
Two filed experiments were carried out at the New Salheyia Region, Sharkia Governorate, during the two successive seasons 2001/2002 and 2002/2003 to study growth and productivity of wheat plants as affected by complete foliar fertilizer compounds under water stress conditions in newly cultivated sandy land.
Mostrar más [+] Menos [-]Taxonomic study of the genus Zygophyllum in Egypt. 1.- morphological features
2003
Ahmed, K.A. | Mohamed, A.H.Azhar Univ., Cairo (Egypt). Faculty of Science (Girls))
Effect of some constituents of citrus essential oil against postharvest pathogenic fungi of citrus fruits
2002
El-Mohamedy, R.S.R. | Abdel-Kareem, F. | Abd-Alla, M.A. (National Research Center, Cairo (Egypt). Plant Pathology Dept.)