In seeking economic production of microbial cellulose, the available and low cost commercial kombucha starter, contains mainly Acetobacter xylinum and Saccharomyces sp., were used under static condition. The best medium composition was black tea extract (1.0 g /100 ml H2O), sucrose (20%) and corn steep liquor, CSL (1%) at 26-28oC for 10 days. The cellulose yield (1.3 g /100 ml) and productive rate (1.3 X 10-3 g / day /ml) were higher than some reported values. Addition of folic acid or its building block p-aminobenzoic acid at additive concentrations 0.20% led to dou-bling the yield (2.37 and 2.43 g / 100 ml culture respectively) and the productive rate (2.37 X 10-3 and 2.43 X 10-3 g / day / ml respectively). Scan-ning electron micrograph showed the structure of the produced microbial cellulose fibrils without any microbial flora after treatment with 1% NaOH.

Avocado fruits (Persea americana Mill) cv. Fuerte and white sapote (Casimiroa edulis) cv. Rotaceae cultivated in Egypt were collected at different maturity stages:green mature,commercial ripe and over ripe stages. The headspace volatiles of each maturity stage was isolated and subjected to gas chromatography- mass spectrometric analy-sis. A total of 43 components were identified in avocado aroma including; terpenes (15), esters (8), aldehydes (8), alcohols (6), ketones (2), thiazoles (l), pyridines (1), toluene and acetic acid, where as 18 compounds were, identified in casimiroa aro-ma, they contained (4) esters, (6) alcohols, (4) aldehydes, (3) terpenes and (1) ketone. Ethanol (Z)-3- hexenol and (E)-2- hexenal were the major constituents in green and ripe fruits of avocado whereas they decreased at the final stage of matu-ration. Over ripe avocado fruits had the highest content of esters (ethyl ethanoate, ethyl acetate and methyl propanoate) and terpenoides especially d-limonene and z-nerolidol. Esters and alcohols comprised more than 85% of the total concentra-tion of volatiles in casimiroa fruits during three stages of maturation. The highest content of ethyl butanoate (sweet and fruity aroma) and ethanol revealed the most prominent effect on consumer acceptability of the cosimiroa flavour attributes. It is obvious that maturation of the fruits was associ-ated with remarkable changes in the volatiles that mainly affect their flavour.

The present study was carried out to investi-gate the effect of pruning method on growth and production of cucumber (hybrid Aula) grown in greenhouses for 2004 and 2005 growing seasons. Three types of pruning were used : system of prin-cipal stem, system of secondary branchs, and mixed system (principal stem + secondary branchs). The results show the following points * Effect of mixed system is distinguish on early and total production in comparison with the other used methods which present a comparable production. * Failing growth and production of mixed system at the end of season compared with two other used methods. This experience allows to suggest * Use of mixed system necessitate the regular pruning of plants for avoid the physiological fail and the bad morphological and physiologi-cal characteristics of fruits. * Possibility of application the system of principal stem and avoid the system of secondary branchs with the necessity of knowledge the type of branch of varieties for avoid the tardy production

The effect of exposing of potato tubers cv. Di-amond to ethyl salicylic acid (ES) vapour for dif-ferent doses and different periods of exposing on rots incidence and sprouting of tubers under long term storage was studied. Expose of tubers to high doses of vapour (resulted from evaporation of 0.5 or 1 ml/ liter space) for 6 h led to appear a very strong harmful effect on exposed tubers stored for 4 months. All tubers were decayed, collapsed and severely infected by rot pathogens. Expose of tu-bers to middle dose (0.25 ml/liter space) for 6, 12, 24, or 48 h then stored for 4 months at ambient temperature showed variable effects. Six or 12 h exposing led to slight reduction of rot incidence but it had not effect on sprouting in comparison to non-exposed tubers. On the other hand, exposing, for 24 or 48 h suppressed sprouting completely and reduced to very great extent rots incidence (%). Storage of tubers exposed to 0.25 ml/ liter for 24 h at high relative humidity (~90%) or under cooling (6-8 Cْ ) did not cause any reduction in compound efficiency. Expose of tubers to low dose of ES vapour (0.125 ml/ liter space) for dif-ferent periods showed that exposing for 6 or 12 h led to stimulatory effect on sprouting without ef-fect on rots incidence. Twenty four hours exposing led to decrease rots incidence and sprouting.These results clearly indicated that ES vapour had variable effects on exposed tubers depend upon dose and period of exposing.

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

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.

A two years (2002/2003, 2003/2004) study was conducted at Hada Al-Sham Agriculture Re-search Station, Makkah Region (King Abdulaziz University) to determine the effects of three dif-ferent dripper discharges (0.5, 1, and 2 gph) on cabbage production, characteristics of its part and its nitrogen contents in whole plant and its parts. Results show a significant increase in Copenhagen variety production (38.5 tone/ha) as compared to Bronzweek Variety (30.2 tone/ha). Also, the drip-per discharge significantly affected the cabbage production, characteristics of head, stem, root or leaves area, whereas cabbage production and char-acteristics of all plant parts (head, stem, root and leaves area) were reduced with the increase in dripper discharge more than 0.5 gph, however, the reduction was not significant between discharges of 1 and 2 gph. The cabbage production were 44.3, 29.7 and 28.9 tone/ha for dripper discharges of 0.5, 1 and 2 gph, respectively). In addition, the interaction between season and variety had only significant effects on root length. Also, there were significant effects for the interaction between dripper discharge and season on cabbage produc-tion and root length. Results also showed that first season (2003) produced cabbage plant significant-ly higher than the second season (2004) in nitro-gen content for both whole plant (2.72% and 2.45% for first and second season, respectively) and head (3.63% and 2.72% for first and second season, respectively). Also, Copenhagen variety significantly outweighs Bronzweek variety on nitrogen content in whole plant (2.88% and 2.30% for Copenhagen variety and Bronzweek variety, respectively), leaf (2.69% and 2.16% for Copen-hagen variety and Bronzweek variety, respective-ly), and stem (2.72% and 2.08% for Copenhagen variety and Bronzweek variety, respectively). On the other hand, the increase in dripper discharge more than 0.5 gph resulted significant reduction in nitrogen content for whole plant (3.10%, 2.44% and 2.22% for dripper discharges of 0.5, 1 and 2 gph, respectively) and its parts (head, stem and leaves) whereas the dripper with less discharge (0.5 gph) outweigh the higher discharge drippers (1 and 2 gph). However, the increase of dripper discharge from 1 gph to 2 gph had only significant reduction in the nitrogen content of head. The re-sults also show that interaction between season and variety had only significant effects on nitro-gen content in whole plant. There were also signif-icant effects for the interaction between season and drip discharge on nitrogen content of whole plant and its leaf.

Two field experiments were carried out to evaluate six mutant lines having a good agronomic potential comparing with their original varieties Sids5, Sids6 and Sids7. The results showed signif-icant decrease in plant height for all semidwarf mutant lines. The reduction of plant height reached to 19.83% comparing with the original varieties. Some semidwarf mutant lines (line 5-1, line 6-1 and line 7-1) exhibited highly significant values for spike length, number of spikes/plant and grain yield/plant as compared to their original varieties. The original varieties manifested highly significant values for number of grains/spike as compared to their all semidwarf mutant lines. The results indicated that wheat semidwarf mutants of line 5-1, line 6-1 and line 7-1 are promising mu-tant lines, since they gave high grain yield. All studied genotypes were electrophoreticaly ana-lyzed for grain water-soluble proteins. The dis-crimination of such mutant lines and their parental varieties revealed differences in their banding pat-terns and occurrence of genetic variation between such genotypes. The electrophoretic analyses of proteins revealed some newly induced bands such as bands with molecular weights of 114.04, 87.82, 41.55 and 11.90 kDa. Such newly bands, which were not existed in the unirradiated varieties, may be originated from gamma radiation effects. It is expected that gamma rays modified the structure of some genes in the mutant lines, and these modi-fications appeared as absence of protein bands with molecular weights of 72.60 kDa in sids5 and 24.39 kDa in Sids6. The variety Sids7 exhibited the highest numbers of new protein bands after irradiation. The results revealed positive relations

Sixteen yeast isolates from various sources in-cluding molasses, foodstuffs, concentrated juices and soils were identified using simplified API 20 C AUX yeast identification system and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The isolates were found to belong to 11 species; Candida famata, C. glabra-ta, C. krusei / inconspicua, C. norvegensis, C. col-liculosa, Cryptococcus humicolus, Rhodotorula mucilaginosa, Kloeckera spp., Geotrichum capita-tum and Saccharomyces cerevisiae. API and RAPD-PCR proved to be useful and convenient taxonomic tools for rapid identification at the spe-cies level, proving that at least two techniques are needed for precise identification. RAPD-PCR pro-cedure is faster than traditional characterization techniques; the identification of a single colony was typically achieved in less than 10 hr.