The effect of the forward speed of a potato harvester on tubers damage was in-vestigated. The potato harvester type is a two-row potato digger with riddle chain. The experiments were conducted in a potato field of Haradh Project of the National Agricultural Development Company (NADEC) east of Riyadh, in a sandy loam soil, and for a potato crop planted during the spring season of 2004. The potato type was Hermes (oval graded tubers). The degging depth was set to 22 cm, and the ampli-tudes of riddle chain of the implement were 17 and 25 mm. Results showed that the average values of tubers lifting percentage were in close agreement for all forward speed values (1.5, 1.7, and 2 km/h) of the potato harvester. However, it ranged be-tween 96% and 99%. It was found that there is no significant effect of the forward speed on both total damaged tubers percentage and damage index. However, there was a significant difference for the damaged tubers percentage when the amplitude of riddle chain was changed from 17 to 25 mm, where it decreased as the amplitude was increased. The values of potato damage index for all forward speeds were with-in acceptable limits of damage index. Minimum value of damage index was 0.04 at the speed of 2 km/h and amplitude of 25 mm.

Laboratory and field trials were carried out at Koom Hamada district and Etay El-baroud research station during 2004/ 2005 season to clarify the molluscicidal ac-tivities of the following: indoxacarb, lufenuron, Bacillus thurringiensis, kurestaci (Bt.) and methomyl against glassy clover snails Monacha cartusiana (Müler). Re-sults indicated that all tested pesticides decreased snails population compared with control. Under the field conditions, the efficiency of the tested compounds were 98.0, 93.4, 93 and 71.58% for methomyl, lufenuron, indoxacarb and Bt. after 5, 6, 13, and 28 days of treatment, respectively. Moreover the effect of LC50 and 0.5 LC50 of these compounds were investigated on some biochemical parameters in vivo. The activities of acetylcholinestrase (AChE), alanine aminotransferases (ALT) , as-partate aminotransferases (AST) and protein contents at different time intervals were evaluated. The specific activity of AChE reached 0.009, 0.002, 0.006 and 0.001 mole/ mg protein/ min for indoxacarb, lufenuron, Bt. and methomyl, respectively, after one day of treatment with (LC50 for each compound). In general, Bt. and in-doxacarb caused slight inhibition on AChE enzyme. All treatments decreased ALT and AST enzyme activity in the tested animals. However, Bt. Showed slight effect on the activity of aminotransferases enzymes.

A field experiment was carried out in a newly cultivated soil at Falouga, El-Tahrir province, Behira governorate during the summer season (Spring plantation)of 2003 to investigate the effect of different organic manures (i.e. compost, F Y Mor town refuse) each at rate of 20 ton/fed combined with the half recommended doseof mineral fertilizer (NPK) or 2 tons of chicken manure compared with the additionof the recommended dose of N P K at rate of 900, 400 and 200 Kg/fed ammoniumsulphate, calcium superphosphate and potassium sulphate respectively. Applicationof organic manures, i.e. compost, FYM or town refuse each at the rate of 20tons/fed combined with half amount of mineral fertilizer or 2 tons of chickenmanure, increased total microbial count in soil at 60 days after planting compared toboth uncultivated soil and chemical fertilized treatments. In this regard, the highestbacterial count was noticed in case of using FYM + chicken manure, while thehighest count for total fungi and actinomycetes were recorded in the treatment of 20tons compost + half amount of chemical fertilizer (NPK). In addition, using 20 toncompost + 2 tons of chicken manures/fed, reflected the highest dry matter yield,total nitrogen, phosphorus and potassium content in plant foliage as well as totaltuber yield of potatoes compared with other tested treatments.

Microbiological assay of 150 samples of dairy products for the incidence of Co-liforms, E. coli, E. coli 0157:H7 and non-0157 E.coli, show the recovery of the Coli-forms and E.coli from the tested products with different incidence percentage. Strains of E. coli 0157:H7 and non-0157 E .coli were recovered from 9 (6%) and 13(8.6%) of the total samples, respectively. The behaviour of these isolates were tested when exposing to low pH, salt, low holding temperature and heat treatment. The results indicate obvious survival of E. coli 0157:H7 and non-0157serotype with pH as low as 3.8 pH for 5 days. Also, survival or even multiplication in TSB con-taining <6% salt. Moreover, the strains remained viable at low holding temperature (5oC). So, the product which contaminated with this pathogens remain hazardous even under such stress condition. Decimal reduction times (D-values) of cells sus-pended in saline solution, TSB medium, reconctituted dry milk and chocolate milk were determined. The greatest survival as evidenced by highest D and Z values oc-curred with chocolate milk. Product composition and type of strain affected the heat lethality rates.

Two pot experiments were performed in Giza research station, AgriculturalResearch Center (ARC) using 2 isolates of Pink-Pigmented FacultativelyMethylotrophic bacteria (PPFMs) originated from chickpea and Faba bean. Foliarapplication with PPFM isolates were conjugated with specific rhizobial inoculumand N-fertilization (15 Kg N Fed-1). Nodulation status, nitrogen fixation and growthyield and yield component were recorded. Results clearly indicated that Chickpeawas superior in its response to foliar application with PPFM.C. As it gave higherrecords of number and dry weight of nodules, dry matter and N-content of plants ascompared to Faba bean. A field experiment was also conducted in sandy loam soil atSouth EL-Tahreer province to investigate the effect of foliar application withPPFM.C strain + specific Rhizobia and N-fertilization on nodulation, growth andyield of chickpea legume plants. Results indicated that foliar application withPPFM.C in the presence of specific rhizobial inoculation scored significant increasesin economic turnover of chickpea in the range of 21-32% as compared to Nfertilizationat rate 50 Kg N Fed-1. Foliar application with 5 L Fed-1 in the presenceof 15 Kg N Fed-1 and specific rhizobial inoculation led to an increase of 518 kg fed -1productivity of seed yield , with economic turnover of 2491 L.E.

The production of probiotic low calorie sour cream was aimed to experiment in relation to its compositional, bacteriological, biochemical, rheological and organo-leptic properties along the cold storage period of the product. Cream based on 36% total solids (TS) and 30 % fat was made using the obtained fresh cream (54 % TS and 50 % fat) and liquid skimmed milk (9 % TS).To produce low-calorie sour cream, fat content was lowered to 20 and 10 % depending on the addition of Sim-plesse100® to mimic milk fat on the basic of 0.1% fat mimetic is instead of 1.0% fat. Dried whey protein concentrate (DWPC, 95 % TS) was used as bulking agent to overcome the loss occurred in the TS content due to the reduction in the fat content. Thereafter, all creams were homogenized at 55-60°C and further heat treated to 74°C for 30 sec. followed by rapidly cooling to the appropriate temperatures. Then creams were inoculated with 2% freshly prepared bacterial starter culture and incu-bated at 30 or 37 °C, to reach pH value about 4.6, for cream cultured with R-704 or ABT-2 type starter culture, respectively. The results indicated that, the proportional fat replacement of cream led to gradual increase in the protein, carbohydrate and ash contents, and decreased the caloric value. There are a backward relationship between the bacterial population and the fat content of the sour cream. Where, in the product cultured with ABT-2 type, Lactobacillus acidophilus grew and predominated in all other accompanying strains overlooking either the fat content or the cold storage pe-riod (CSP). Streptococcus thermophilus populated the 2nd predominance order fol-lowed by Bifidobacterium sp., which tended to proximate and preceded, actually, Str. thermophilus by prolonging the CSP of the lowest fat-content cream (10%). The increase rate of the bacterial count continued until 3rd weak for Lb. acidophilus and to 1st weak for Bifidobacterium sp.. Thereafter, gradual decreases were occurred. However, Str. thermophilus began to decrease from the 1st day of CSP. Although the count of bacterial type R-704 was always higher, it behaved a trend similar to that of Bifidobacterium sp. toward the CSP. Sour cream of ABT-2 type contained higher ti-tratable acidity (TA) % as well as lower pH, acetaldehyde (AC) and diacetyl (DA) values than that cultured with R-704 type. Along CSP of sour cream the increment in AC, DA and TA contents continued, in order, until the 7th , 14th and the end of theFayed; Gehan Hussein and Azza FarahatArab Univ. J. Agric. Sci., 14(2), 2006experimental period. As the protein content raised at the expanse of the fat content via adding DWPC, which was in the denatured form, the firmness, consistency coef-ficient, and yield stress of sour cream increased, especially when ABT-2 type was used and the CSP progressed. Furthermore, ABT-2 sour cream was sensory distin-guished with, nearly, similar appearance as will as better flavour and consistency ra-ther than that of R-704. The fat reduction to 20 % did not influence the overall sen-sory quality, while that of 10% fat attained panel score averaged 93.5 % of the con-trol when ABT-2 type was used. As a conclusion, it is successfully possible to pro-duce probiotic low calorie sour cream with excellent sensory attributes using Sim-plesse100® as fat mimetic and bacterial type ABT-2 as starter culture.

The seasonal activity of the peach twig borer, Anarsia lineatella Zeller was in-vestigated during 2004 and 2005 seasons. The data revealed that the infested twigs empty from larvae (15%) were higher than that with larvae (1.25%) in February. The situation was reverse in April which recorded 8% and 14.75% for both, respec-tively. In fruits, infestation began to appear in the third week of March which rec-orded 2% whereas the maximum rate was recorded in May (16.75%). Three species of hymenopterous parasitoids were found; Apanteles ruficrus Haliday (Fam. Braco-nidae), Diplazon laetatorus Fab. (Fam. Ichneumonidae) and Microgaster tiro Rein-hard (Fam. Braconidae). These parasitoids reached its maximum during April (13.5%) that seems to be more active. Their numbers were positively correlated with the rate of infestation (r = + 0.799). In spite of presence of four predatory species (Coccinella undecimpunctata L., Rodalia cardinalis Mulsant, and Scymnus syriacus Marseul (Coleoptera: Coccinellidae) and Syrphus sp. (Diptera: Syrphidae)), it seems to be less active. Their numbers recorded very slight positive correlation with the rate of infestation (r =+0.423)

A kairomone from adult Cydia pomonella L. scales is an important factor in the host recognition and searching behaviour process of Trichogramma cacoeciae Mar-chal and Trichogramma dendrolimi Matsumura. The Trichogramma spp. used the chemicals from the host eggs for orientation to host and increased their parasitism. The females of T. cacoeciae*, T. dendrolimi** and T. dendrolimi*** contacted the unwashed host eggs significantly longer than the washed eggs. Washing the codling moth eggs with hexan significantly reduced the parasitism of all the tested Tricho-gramma strains compared to unwashed eggs. The treated apple trees with wing scales of C. pomonella had significant influence on the parasitism compared to un-treated trees. The percentage parasitism of codling moth eggs on the treated trees (31.6%) was significantly higher than on the untreated trees (19.3%).

Dithiocarbamate mancozeb, an organometallic fungicide, was administered orally to male Wistar rats in two forms, pure technical 85% and formulated 80% WP, at sublethal doses of 125, 250 and 500 mg/kg b.w. for 28 days. Clinical chemical endpoints were measured after 2, 3, and 4 weeks of treatment initiation.  Data disclosed that both compound formulations affected significantly serum enzyme activities particularly liver enzymes in a dose and time-dependent manner, compared with control. Such changes were accompanied with significant alterations in other parameters like; total protein, albumin, glucose, total lipids, triglycerides, cholestrol, urea, and creatinine.  Furthermore, histological examination of liver and kidney showed several histopathogenic ubnormalities in the examined tissues of rats exposed to mancozeb either technical or formulated.

Twenty one mite species belonging to 3 suborders and 11 families were found in grain residues and mixed flour samples collected from warehouses and mills at Great Cairo. They were 12 pest species, 7 predatory and 2 parasitic species. Species commonly found in all inspected materials at all locations were Dermatophagoides farinae Hughes, Tyrophagous putrescentiae (Sch.) and Cheyletus malaccensis Oud. However Acrus siro (Lin), Acarophenax tribolii (New.) and Pyemotes herfsi (Oud.) were often abundant. The remaining species occurred sporadically in the collected materials. Actinedid and acaridid mites were “dominant” and “constant” in mixed flour and grain residues samples, the second group was the most abundant. Whereas gamasid mites was “recedent” and “accidental”. Mixed flour taken from Qaliobia Governorate harboured the highest number of mite species (15 species) followed by grain residues from Giza Governorate (13 species). While grain residues taken from Cairo Governorate harboured the lowest number (5 species).The highest infestation level with mites (2677.3 individuals) was recorded in mixed flour at Qaliobia Governorate, while the lowest one (1067 individuals) was found in grain residues at Cairo Governorate. Generally, mixed flour harboured more mite species than grain residues. Most of the collected mite species occurred during autumn and winter except P. herfsi and A. tribolii which were recorded during spring and summer, respectively. Dominance and frequency of occurrence, population fluctuations, effect of temperature and relative humidity on the population dynamics, also the relation between the predators and pests of mites were discussed in details.