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91.
92.
The aim of the study is to determine the effect of different growth vigorous rootstocks on phenolic compounds in leaves of apple. For this purpose it was used the leaves of cultivar ‘Red Chief’ grafted on dwarf (M9), semi-dwarf (M26) and semi-vigorous (MM106) rootstocks. During mid-July, the leaf samples were taken from the middle part of annual shoots. Phenolics of the leaves were determined by HPLC analysis. While significant differences among the rootstocks for p-hydroxybenzoic acid, eriodictyol, ferulic acid and p-coumaric acid were detected, these differences were insignificant for gallic acid and quercetin. It was shown that semi-vigorous rootstocks (MM106) had higher phenolic contents in total than the other two dwarf rootstocks. In addition, apigenin-7-glucoside, chlorogenic acid, caffeic acid, rosmarinic acid, epicatechin, syringic acid, catechin, rutin, resveratrol, hesperidin, naringenin, luteolin, apigenin and acacetin could not to be detected. Data showed that there is the relationship between growth vigour and phenolic contents of apple leaves. Especially, p-hydroxy benzoic acid and p-coumaric acid contents were higher in semi-vigorous rootstock than in dwarf rootstock.  相似文献   
93.
The adaptation of the primary internal parasitoid,Trichogramma evanescens (Westw.), as an egg parasitoid ofLobesia botrana (Den. & Schiff.) was the first report in Alexandria region, Egypt. The life-span of this parasitoid on eggs ofL. botrana andSitotroga cerealella Ol. was investigated. The duration from egg to adult, longevity of adult stage, sex-ratio and total life cycle each of the two hosts were recorded. The ovipositional periods of mated females ofT. evanescens on egg ofL. botrana at 27±2co and 75±2% R.H. were studied. Also, percentages of parasitism byT. evanescens ranged from 22%–64% on the eggs ofL. botrana. Therefore, this parasitoid was very efficient as a biocontrol agent against the most serious grape pestL. botrana in Egypt.  相似文献   
94.
In Egypt, the reclamation of new lands takes place on the fringes of the Nile Valley and Delta. Few years after the reclamation of new lands, water logging problems developed in the adjacent traditionally cultivated lands. The extent of the problem is considerably large, thus imposing constraint to land productivity. This dictates thorough investigations of the causes of and possible solutions to relief these problems. This paper presents the results of investigations carried out in order to identify the causes and extent of water logging problems in Beni Suef and Minia Governorates as a result of reclaiming two areas on their fringes. Proposed short and long-term solutions are also given.  相似文献   
95.
The effect of natural grasses namely Ghab (Phragmites communis) and Nisela (Panicum repens) compared to leaching and gypsum addition on reducing the salinity and alkalinity of heavy clay texture salt affected soil in northern Egypt was investigated for 2 years. In a field experiment 18 plots (6×7 m2 each) were prepared for six treatments. Each treatment had three replicates. The treatments were ponding (8–10 cm water depth), gypsum (12 t per feddan, where one feddan=4200 m2) and the last four treatments were cultivation of Ghab and Nisela with and without gypsum.

Ghab and Nisela grasses reduced the salinity of the upper 50 cm soil layer more than leaching in both years. The reduction was more pronounced after the second year. The relative EC for the upper 50 cm after the first year compared to its initial value was in the range of 26.8–44.7% for ponding, 30.3–45.6% for gypsum, 23.6–42.2% for Ghab, 21.2–35.9% for Nisela, 20.9–40.1% for Ghab+gypsum and 19.7–32.5% for Nisela+gypsum. The reduction was even greater after the second year and reached to its maximum at Nisela+gypsum (5.5–5.9%). However, the reduction of the sodium adsorption ratio (SAR) took the same trend recorded with salinity but with less magnitude in both years. Therefore, Ghab and Nisela reduced both salinity and alkalinity of the upper surface layer more than leaching or gypsum and produced high fresh yield which could be utilized in livestock fodder during the reclamation of such unproductive soils.  相似文献   

96.
Pregnancy toxemia is a metabolic disease of pregnant ewes which causes significant economic losses in sheep industry. The pathophysiology and metabolic changes of this disorder remain poorly understood. We conducted this study to describe the serum protein pattern associated with the pregnancy toxemia in ewes. In this study, the electrophoretic pattern of serum proteins of 15 ewes with naturally occuring pregnancy toxemia and 12 ewes with uncomplicated pregnant were investigated by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Serum protein patterns were mainly characterized by four bands and located in the 76 kDa, 66 kDa, 55 kDa and 29 kDa both diseased and control groups. The percent of the 66 kDa, 55 kDa and 29 kDa proteins were decreased (P < 0.001 for 66 kDa; P < 0.01 for 55 kDa and P < 0.05 for 29 kDa) while 76 kDa (P < 0.05) protein was significantly increased (P < 0.001) in ewes with pregnancy toxemia relative to controls. Positive correlations were found between activities of liver enzymes and percentage of the distribution in 76 kDa, 55 kDa proteins. In contrast, there was a negative correlation between the 66 kDa protein and liver enzymes. In conclusion, the results of this study demonstrate that the percentages of the 76 kDa, 66 kDa, 55 kDa and 29 kDa proteins are significantly altered in ewes with pregnancy toxemia. However, further studies are needed to explore the potential role of these alterations in the pathophysiology in ewe with pregnancy toxemia.  相似文献   
97.
The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats' milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August 2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected. Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4), 3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton–Valentine leukocidin produced by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity.  相似文献   
98.
Variation in metabolite composition and content is often observed in citrus, however, it is poorly understood to what extent this variation has a genetic basis. C. aurantium genotypes originating from Tunisia were evaluated to detect genomic (SSR markers) and chemotypic polymorphisms and to discover possible associations between them. A total of fifteen highly polymorphic SSR markers were selected to screen the genetic variability of the most widespread sour orange genotypes. Targeted secondary metabolite profiling analysis generated twenty-one compounds differentially accumulated in the leaves of sour orange genotypes. PCA analysis revealed that genomic and chemotypic data generated similar pattern of clustering, highlighting the intra-specific variability in C. aurantium species. Both data were integrated, leading to the identification of associated SSR alleles with secondary metabolites. Based on results, a relatively high correlation (r = 0.381; p < 0.0001) between chemotypic patterns and genetic markers was identified. Associations between traits of interest for phenolic compounds and genetic markers were tested using statistical methods including three linear model approaches. These results consolidate the presence of a chemical fingerprint that may be suitable for assessing identity and quality of a particular genotype which will be very useful for citrus breeding programs.  相似文献   
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