This study was conducted in a sandy soil at Ali Mubarak Village Research Farm, South Tahrir Horticulture Research Station, Behaira Gover-norate, during the two successive seasons of 2002/2003 and 2003/2004 on sweet corn Jubilee hybrid. The study aimed to determine the best treatments of nitrogen fertigation level and chelat-ed calcium foliar application on the productivity and quality of sweet corn. The obtained results indicated that increasing nitrogen fertigation level (100, 120, 140 to 160) kg N/fed. and (or) chelated calcium (12% Ca++) concentration (500 and 1000 ppm Ca EDTA) led to increasing the vegetative growth (leaf area, plant height, fresh and dry weight), chemical composition (total chlorophyll, nitrogen, phosphorus, potassium and calcium in leaves) and yield characters (ear length, ear diame-ter, weight of 1000 seed, unhusked ear, husked ear and total yield) The promising treatment was 160 kg N/Fed. combined with 1000 ppm Ca EDTA under similar prevailing conditions of the present studying in a sandy soil

A field experiment was conducted at the exper-imental farm of the Faculty of Agriculture, Ain Shams University, Shoubra Elkheima, Kalubia governorate, during 2002/2003 and 2003/2004 seasons to study the effects of three sowing dates, i.e., the first of each of September, October and November, and four pinching treatments (pinching the apical head just after appearance, pinching the main head at the marketable stage, pinching the axillary head just after appearance (disbudding) and without pinching) on broccoli plants (Brassica olerasea var Italica), cultivar “Emperor”. Plants were grown in Kaliobia under loamy soil conditions. Plants of the second sowing date (first of October) produced the tallest plants and the highest number of leaves per plant. Plants grown on the first of October plantation, pinching the main head at the marketable stage or the com-bination between them recorded the highest values of number of siliques/ plant, number of seeds/ plant, and seed yield.

This study was conducted in loamy soil at Qaha Experimental Station, Horticulture Research Institute, ARC, Kalubia governorate, during 2002/2003 and 2003/2004 seasons to study the effect of PEG and planting methods on sweet corn productivity. The obtained results indicated that GSS 9377 F1 hybrid plants produced vigorous growth and higher early and total yield than those of Endeavor F1 hybrid. Direct seeding in the open field or under tunnels increased plant height, stem diameter, number of leaves/plant, plant fresh weight, unhusked ear weight, husked ear weight and total yield compared to transplanting methods. Transplanting produced the higher early yield ei-ther with open field or under tunnels. Primed seeds of sweet corn F1 hybrids (GSS 9377 and Endeavor) in PEG 6000 dalton for 6 hours at the concentration of 400 g/L produced taller plants with thicker stem diameter, higher number of leaves/plant and greater fresh weight, higher un-husked and husked ear weight, ear length, higher TSS as well as early and total yield compared to check untreated seeds

Two experiments were consummated at the Experimental Farm, National Research Center (NRC), Dokki, Cairo, Egypt during two succes-sive seasons of 2004/2005 and 2005/2006 to eval-uate the effect of natural products as a source of some important elements such as rock phosphate as a source of phosphorous and feldspar mica as a source of potassium with biological potassium phosphorous fertilizer or biological potassium fertilizer (Silicate bacterium) at different levels (0.0, 25, 50 and 100 g/L) on Ruta graveolens L. plant instead of the chemical fertilizes. Adding biological fertilizer with feldspar or rock phos-phate improved vegetative growth characters such as plant height (cm), branches number/ plant, fresh and dry weights of different plant parts i.e. leaves, stems and roots (g/plant), in addition to some chemical constituents as essential oil, total flavo-noides, P, K, Fe, Zn and Cu content. On the other hand, the main constituents of essential oil and N content were decreased compared with adding recommended chemical fertilizers.

Different applications [various potato cultivars, chemical fertilizers, bioagents and chemical in-ducers] were used for controlling brown rot dis-ease of potato. Potato cultivars namely Diamant, Desiree, Herms, Lady Joy, Lady Rossetta, Nicola, Spunta and Valor were variably susceptible to Ralstonia solanacearum, the causal pathogen of brown rot disease. Herms cultivar was the least susceptible. Application of ammonium sulfate, potassium sulfate, Urea, and calcium superphos-phate to infested soil as a single amendment re-duced disease incidence. Application of calcium superphosphate was the most effective treatment. The bioagents Pseudomonas fluorescens, Pseu-domonas putida and Bacillus subtilis were effec-tive in controlling disease when were used sepa-rately and Pseudomonas putida was the most effi-cient. Foliar spraying with different inducers sin-gly [salicylic acid, di-potassium hydrogen phos-phate and tri-potassium phosphate] reduced the disease incidence. Tri-potassium phosphate was the most effective against the disease. Therefore, a management programme was suggested including cultivar Herms, calcium superphosphate, Pseudo-monas putida and tri-potassium phosphate, as in-tegrated treatment. Rotation of these agents showed high effectiveness to disease control as well on the yield increase.

This study aims at clarifying the most important factors that control using and recycling of farm residues. Also, determining the contribution of these factors in the quantity used or recycled by the farmer. The results showed that, the most im-portant factors for amount percentage of wheat straw used as forage, were number of farm ani-mals, price of green forage/ ton and straw stores which together accounted for 78% of the amount percentage. On the other hand, the most important factors for sold quantity of wheat straw were number of farm animals and transporting means which together accounted for 51% in that amount. The study showed also that the most important factors of the recycled amount of rice straw werecosts of recycling rice straw to forage and fertiliz-er, price of compost/ ton and price of nitrogen fertilizers/ ton. These factors together accounted for 88% of the total variability of the recycled amount. The most import contributing factors in the amount of maize straw recycled to silage were straw recycling costs, number of farm animals and extension. These factors contributed to 87% in that recycled amount. The most contributing factors in the cotton straw used as fuel were number of fami-ly members and oil fuel used. These two factors accounted for 66% of variation of straw amount. The study recommends that establishment of agri-cultural policy is necessary to get rid of farm resi-dues using modern technology i.e recycling of farm residues to reduce environment pollution and to develop the agricultural sector to achieve sus-tainable agricultural development.

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.

This work was carried out in two successive summer plantations of 2004 and 2005 on potatoes cv. Spunta at Abou Awad village , Aga, Dakahlia Governorate, to study the influence of Vesicular Arbuscular Mycorrhizal (VAM) fungi , nitrogen and potassium fertilization at rates of 50, 75 and 100% of recommended rate / fed. with foliar spraying of micronutrients (Fe150 , Zn 75, and Mn 75 ppm) and their interactions on plant growth , yield and its components, as well as chemical composition .Application of the tested rates of nitrogen and the potassium induced significant increase in vegetative characteristics (plant height, foliage fresh and foliage dry weight) total tuber yield (t/fed) , number of tubers/plant and tuber weight/plant, tuber dry matter , starch and nitrate content in tuber, as well as N,P and K concentra-tions in the leaves and micronutrients in the leaves (Fe, Mn and Zn) in both seasons.Similarly, plant height, chlorophyll content, fo-liage fresh and dry weights , total yield (t/fed), number of tubers , tuber weight/ plant, tuber dry weight , starch and nitrate content in tuber, NPK concentration in leaves and tubers , micronutrient content (Fe, Zn and Mn) in leaves gave the highest values with inoculation by VA Mycorrhizal fungi and some micronutrients .The interaction between NK, VAM fungi and micronutrient gave the highest values of vege-tative growth characteristics, number of tu-bers/plant, NPK in leaves and tubers and micronu-trients (Zn and Mn) in leaves when potatoes was fertilized with 100% NK of the recommended rate and inoculate with VAM fungi plus foliar spraying by micronutrients (Fe, Zn and Mn).as well as total yield (t/fed), tuber weight/plant, tuber dry weight, starch content in tuber , Mn and Zn in leaves, while The lowest content of nitrate in tubers was found when plants were applied with 50 (%) NK of recommended rate with inoculation by VA My-corrhizal fungi.Generally, the best results were obtained when potato received 75 % of NK of the recommended rate, inoculated by VA Mycorrhizal fungi and sprayed with micronutrients at dose of Fe 150, Mn 75 and Zn 75 ppm. This treatment resulted in the highest total tuber yield and its components and reduced chemical fertilizer inputs.

A field experiment was carried out in sandy soil to elucidate the possibility of using chloride form as a partial source for potassium in fertiga-tion of banana plants grown on a sandy soil. Growth, fruit yield and quality as well as plant nutritional status and Cl accumulation within both plant leaves and rhizosphere beside an economical elucidation were taken in to consideration to ac-complish such evaluation. Eleven gradual increas-ing KCl: KNO3 (0:100 - 100:0) ratios were applied with maintaining the concentration of all macro and micro nutrients except Cl constant. Obtained data indicated that increasing Cl existence didn’t adversely affect plant growth under this experi-ment. Treatments of 10:90 followed by 50:50 as well as 70:30 followed by 80:20 and either 90:10 or 10:90 (KCl:KNO3) were most stimulating treatments for increasing pseudo stem diameter and leaves number, respectively. Although total fruit yield bunch as well as number and length of fingers are less sensitive to increasing KCl:KNO3 ratio, number of hands/bunch and diameters of fingers were significantly and positively affected by increasing KCl existence. Treatment of 80:20 KCl:KNO3 was the most significant superior one for all measured fruit yield parameters. Although Cl content increased significantly in banana leaves and root surrounding area with increasing Cl ex-istence in the fertigation solutions, recorded con-tents seemed to be in safe ranges whereas no chlo-ride necroses symptoms were appeared at banana leaves. Contents of N, P and K as well as Cl in plant leaves were significantly, although in fluctu-ating manner, affected by increasing chloride oc-currence in fertigation solution. The encountered response of N, P and K contents seemed to be not only a resultant of increasing Cl occurrence in the root media but also as a reflection to changing the N form (NH4 and urea) compensating N-NO3 de-cline in the fertigation solutions having high Cl concentrations. The relatively high supplements of Cl (80:20 followed by 70:30 KCl: KNO3) recorded the highest economical net return. It could be con-cluded that KCl can be perfectly used in fertigat-ing banana plants grown on sandy soils. To in-crease safety of using chloride under such condi-tions, more work could be suggested particularly what concerns with calculating irrigation and leaching water requirements to prevent chloride accumulation in the root zone.

Ageratum houstonianum Mill and Tagetes erecta L. (Asteraceae) were subjected to hydrodis-tillation as well as the stepwise extraction with organic solvents. Crude extracts and the hydrodis-tilled essential oils (E.O) were bioevaluated against two phytopathogenic fungi Rhizoctonia solani and Phytophthora megasperma in vitro. The volatile fraction from both plants showed a good antifungal activity towards the tested fungi, EC50s were 91 and 1369 ppm for R. solani and 84 and 1571 ppm for P. megasperma with Ageratum essential oil (E.O) and Tagetes E.O, respectively. But generally; Ageratum E.O was found to be more effective in reducing mycelium growth of R. solani and P. megasperma (EC50 = 91 and 84 ppm respectively) than Tagetes E.O. Chemical compo-sition of Tagetes E.O and Ageratum E.O; fractions F1 (solid) and F2 (liquid) fractions were investi-gated by GC-MS analysis. Interestingly, heterocy-clic benzopyrane compound (Precocene II) was only component which has been detected in Ager-atum E.O fraction F1. Precocene II seems to be the fungitoxic active components in Ageratum E.O and its fractions. However, monoterpenic hydro-carbons were correlated with the fungitoxic effect of Tagetes E.O. In the green house experiments, Tagetes E.O and Ageratum E.O fraction F1 showed a clear selectivity towards tested patho-gens; Rhizoctonia solanii and Phytophthora megasperma. Ageratum E.O; fractions F1 was found to be much more fungitoxic activity than Tagetes E.O. Tagetes E.O and Ageratum E.O frac-tions F1 were controlled the 90.91% of Root-Rot disease in bean caused by Phytophthora megasperma, while the percentage of disease con-trol was only 36.36% for Rhizoctonia solani.