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.

The present study has been carried out on ten stands of Anabasis articulata in Egypt. The relationships between the studied Anabasis articulata stands have been demonstrated as dendrogram based on the morphology, anatomy and some chemical constituents of the plants. Four characteristic ecotypes of Anabasis articulata have been recognized: (i) xerophytic ecotype in the stands of Belbase desert and Sudr El Hytat-Nekhl Road, (ii) xero - halophytiç ecotype in the stands of the Eastern Desert, Sinai Desert, Kattamia-Ain Sukhna Road, Isthmic desert (Fayid), Adabia and Saint Katherine, (iii) halophytic ecotype in the stands of the Red Sea Costal region, Ras Sudr and Hammam Faraon, Sinai and (iv) halo-xerophytic in the stands of the Nekhl-El Hasana and El Hasana-El Quseima Roads. These ecotypes differ, remark-ably, morphologically, anatomically and chemically. This may be due to the varia-tion in climatic and soil characteristics of the habitats

Identification of specific physiological differences among maize genotypes (six inbred lines, four single crosses and four three-way crosses) to drought would be useful to plant breeders for improving selection criteria. Two field experiments were conducted in optimum and stress moisture conditions at Gemmeiza Agricultural Re-search Station in 2001 and 2003 growing seasons. The treatments were 14 geno-types, (six inbreds and eight hybrids), which were separately established under three irrigation treatments in split plot design with four replications. The genotypes were compared under water-deficit conditions on the basis of certain rapid techniques to determine leaf area index (LAI), photosynthetic efficiency (photo), canopy tempera-ture depression (CTD), stomatal conductance (SC) and chlorophyll (CHL) content which were deleteriously affected by water stress in the sensitive genotypes. Results revealed that values of LAI, photosynthetic efficiency, canopy temperature depres-sion, stomatal conductance and chlorophyll content of maize hybrids surpassed those of inbred lines. This was true at 30, 45 and 60 days after planting (DAP). Dif-ferences among maize hybrids and among inbred lines were significant at different growth stages for the same studied traits, except of the LAI for the inbreds, at 30 DAP and CTD for the hybrids at 30 as well as 60 DAP. Detecting certain physio-logical criteria, i.e. LAI, photosynthetic efficiency (photo), canopy temperature de-pression (CTD), stomatal conductance (SC) and chlorophyll content (Chl) could be used as reliable techniques to explore the physiological activity of maize genotypes at early stages of growth and may be recommended in screening different genotypes in maize breeding programs.

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.

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.

Various percentages of citric acid [0.05, 0.1, 0.15 and 0.2%] were blended with the oil (w/v) before the bleaching of either soybean oil (SOO) or sunflower oil (SUO) to rise the performance efficiency of bleaching earth. Afterwards, activated bleaching earth was added to these oils for bleaching them at 1% level. Also, the same clay was used at 2% level for bleaching the above mentioned oils without us-ing citric acid as a reference. The study revealed that better result for raising the bleaching efficiency of SOO was obtained with 0.15% citric acid. Whilst, 0.1% cit-ric acid gave the best result pertaining the bleaching efficiency of SUO. Also, the data showed high reductions in the values of peroxide number, soap, conjugated dienes and trienes for the bleached oils with the increasing percent content of citric acid. While, the acidity values of the bleached oils (SOO and SUO) slightly in-creased with increasing citric acid percentages. On the other hand, using of citric ac-id at the ratios of 0.15 and 0.2% gave almost the same values in the bleaching effi-ciency of SOO. While, using of citric acid at the ratios of 0.1 and 0.15% gave nearly the same results of bleaching efficiency of SUO. Also, the data indicated that using of citric acid caused somewhat no changes in the fatty acid composition or their oxi-dative stabilities in the bleached oils. Therefore, it can be concluded that the reduc-tion in the color of sunflower and / or soybean oils up to a levels of 33.3 and 36.7% is attainable by using either 0.1 or 0.15% citric acid prior to the bleaching step to de-crease the imported content from bleaching earth to Egypt

Two field experiments were carried out at El-Khroub experimental station, east of Constantine, Algeria, to evaluate the effect of N, P, K fertilization and their interaction on growth characters and yield of wheat grown on calcareous soil. The design of each experiment was split-split plot. Urea was applied as folier application to one experiment to evaluate the supplementel application of nitrogen under dry farming conditions. The results showed that the main stem height, number and height  of tillers and number of leaves were varried according to the levels  of  N, P, K fertilization as well as to presence or absence of urea., Straw yield significantly increased due to increasing nitrogen level and potassium fertilization in absence or presence of urea. However, grain yield was significantly increased either with increasing nitrogen level in absence of urea or with increasing phosphorus levels in absence or presence of urea. Straw yield was significantly affected by N * P interaction in absence or presence of urea and N * P * K when urea was applied. However, grain yield was significantly affected by N * P and N * P * K interractions in absence of urea application.

Cotton in Egypt has an important economic situation. Thus the study aimed to evaluate the expected economic effects and productivity of environmental factors on Egyptian cotton production. This comes by predicting production yield value and evaluating its return due to cultural and environmental desired and undesired variables. So, convenient production pattern could be determined to obtain maximum yield under these variables effect. The study clarified that expected cotton yield under desired environmental variables will be ranges between 4169-4336 thousand quintar, with an average equal 4253 thousand quintar. This production will realize national net income ranges between 429.37- 474.68 million L.E., with an average equal 452.03 million L. E. Meanwhile, the expected cotton yield under undesired environmental variables ranges between 3171- 3338 thousand quintar with an average equals 3255 thousand quintar. This yield will realize national net income ranges between 33.37- 78.60 million L. E. with an average equals 55.99 million L.E. The study also indicated that cotton crop is one of the extremely affected crops by the environmental and cultural variables extended in its production zones due its long life period. This is detected by its decrease in the production value undesired environmental factors, where this decrease ranges between 23.02% to 23.94% of the

Flusilazole and triflumizole residues in apple fruits were chemically determined at different periods after spraying of these fungicides under field conditions. The obtained results indicated that, seven days after flusilazole application, unwashed apple fruits were found contained higher residues (0.322 ppm) than the allowed tolerance level (0.2 ppm), while washed and peeled fruits were contained lower residues (0.149 and 0.087 ppm, respectively) after the same period from experiment. These residues were rapidly decreased by elapse of time, so unwashed, washed and peeled apple fruits were contained levels below the allowed MRL i.e. 0.092, 0.008 and <0 ppm, respectively after fourteen days of flusilazole application Accordingly, unwashed apple fruits could be marketed safely 14 days after flusilazole application, while washed and peeled fruits could be used safely after seven days. In the case of triflumizole, unwashed apple fruits were contained 2.030 ppm after five days of application. Such residue is higher than the tolerance value (2.0 ppm), while washed and peeled fruits were contained residues below the tolerance permissive values i.e. 1.010 and 1.970 ppm after three and one days of application, respectively. These values were rapidly decreased by time prolongation, so, unwashed, washed, and peeled apple fruits were contained residues below the allowed tolerance of 1.280, 0.490 and 0.160 ppm at seven days after triflumizole application, respectively. Accordingly, unwashed apple fruits could be marketed safely seven days after triflumizole application, while washed and peeled fruits could used safely three and one days after application, respectively.

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.