Khalaf Ali Fayez Abuamra

استاذ - أستاذ متفرغ

كلية العلوم

العنوان: 17 شارع حنظله بن ربيع –طريق سوهاج اسيوط- سوهاج


2014 | الكلمات المفتاحية salt stress, ;water stress, Oxidative stress, Antioxidant activity,
Improving drought and salinity tolerance in barley by application of salicylic acid and potassium nitrate
Growth and physiological activities of barley (_Hordeum vulgare_ L. cv. Gustoe) grown in soil cultures were evaluated to recognize the ameliorative role of salicylic acid (SA) and KNO3 against the negative effects of salt and water deficit stresses. Barley plants were subjected to three levels of NaCl (50, 100 and 150 mM), three levels of water stress (80%, 70% and ... إقراء المزيد

Isolation and characterization of endophytic bacteria from Plectranthus tenuiflorus medicinal plant in Saudi Arabia desert and their antimicrobial activities
The diversity and beneficial characteristics of endophytic microorganisms have been studied in _Plectranthus tenuiflorus_ medicinal plant. However, information regarding naturally occurring _P. tenuiflorus_ plant associated endophytes among different organs of host is limited. Endophytic bacteria were isolated from root, stem, and leaves of _P. tenuiflorus_ plant. Among 28 endophytic bacterial isolates from different organs of _P. tenuiflorus_ plant, 8 isolates ... إقراء المزيد

Detection and partial characterization of a putative closterovirus affecting Ficus carica: molecular, ultrastructural and physiological aspects of infected leaves
_Fig mosaic disease_ (FMD) was systemically transmitted to susceptible fig plants by grafting and led to development of symptoms including a wide array of discoloration, green blisters, mottling, crinkling and deformation of leaves and fruits. A sensitive assay for the detection of FMV using specific enzyme-linked immune sorbent assay and reverse transcription-polymerase chain reaction was developed. A double-stranded RNA ca. ... إقراء المزيد

2010 | الكلمات المفتاحية Antioxidant capacity,
Modifications of antioxidant activity and protein composition of bean leaf due to Bean yellow mosaic virus infection and salicylic acid treatments
The antioxidant status as well as protein composition of faba bean leaves infected with _Bean yellow mosaic virus_ (BYMV) and the effect of salicylic acid application was examined in this paper. Some modifications in the antioxidant status were observed by changing some antioxidant enzymes activities and contents of antioxidant metabolites. BYMV-infected leaves revealed POD, CAT, APX and SOD induced activities ... إقراء المزيد

2008 | الكلمات المفتاحية Bean yellow mosaic, Faba bean, Photosynthesis, Salicylic acid; Ultrastructure,
Protective action of salicylic acid against bean yellow mosaic virus infection in Vicia faba leaves
In this study, morphological, ultrastructural and physiological modifications of faba bean (_Vicia faba_ cv Giza 461) leaves in response to bean yellow mosaic virus (BYMV) infection and salicylic acid (SA) treatments were examined. Under BYMV stress, leaves showed symptoms including severe mosaic, mottling, crinkling, size reduction and deformations. Three weeks after virus inoculation, photosynthetic rate, pigment contents and transpiration rate ... إقراء المزيد

2007 | الكلمات المفتاحية systemic acquired resistance, salicylic acid, Peroxidase; Pigments, Metabolism,
Physiological and metabolic changes of Cucurbita pepo leaves in response to zucchini yellow mosaic virus (ZYMV) infection and salicylic acid treatments
The changes of some physiological and biochemical parameters in pumpkin (_Cucurbita pepo_ cv Eskandarani) leaves associated with zucchini yellow mosaic virus (ZYMV) infection and the effect of exogenous application of salicylic acid (SA) were studied in this paper. In comparison to the untreated leaves, ZYMV infected leaves showed many symptoms, including severe mosaic, size reduction, stunting and deformation. Results from ... إقراء المزيد

2007 | الكلمات المفتاحية Pigments, Nitrate reductase, Diuron; Growth, C. vulgaris, antioxidant enzymes,
Alteration in growth and physiological activities in Chlorella vulgaris under the effect of photosynthetic inhibitor diuron
In this study, we describe the effect of diuron, a photosynthesis-inhibiting herbicide, on growth, photosynthetic pigment contents, carbohydrate, protein, amino acids, proline, nitrate reductase and some antioxidant enzymes in cell suspensions of Chlorella vulgaris for seven days. The growth (cell number & dry weight) was seriously affected even with lowest diuron dose (0.1 µM). Photosynthetic pigment contents (chl-a, chl-b & ... إقراء المزيد

2006 | الكلمات المفتاحية Photosynthesis rate, Leaf growth;,
Salicylic acid alleviates growth inhibition and oxidative stress caused by zucchini yellow mosaic virus infection in Cucurbita pepo leaves
The effects of zucchini yellow mosaic virus (ZYMV) infection and pretreatments with salicylic acid (SA) on biomass accumulation of pumpkin (_Cucurbita pepo_ cv. Eskandarani) were investigated. The response of photosynthesis, transpiration and the activities of antioxidant enzymes in leaves was also considered. Significant reductions in growth parameters (i.e. leaf area, biomass and shoot height), photosynthesis and chlorophyll _a_ and _b_ ... إقراء المزيد

2000 | الكلمات المفتاحية ultrastructure; proline, Diuron;, Soybean,
Action of photosynthetic diuron herbicide on cell organelles and biochemical constituents of the leaves of two soybean cultivars
Two varieties of soybean (_Glycine max_ L. cv. Clark and Crawford) showed a high sensitivity to low concentrations of diuron herbicide [3-(3,4-dichlorophenyl)-1,1-dimethyl urea]. Depending on the application dose of diuron, chlorosis, necrosis, and wilting of leaves ending in death after 7 to 10 days were observed. These symptoms were more obvious in the Clark variety even at the lowest concentration ... إقراء المزيد

1998 | الكلمات المفتاحية
Physiological studies on nuclear-organelle interaction of cybrid plants containing Solanum nigrum genome and Solanum tuberosum plastome
Comparison between second generation of functional cybrid (containing Solanum nigrum genome and Solanum tuberosum plastome) and original (S. nigrum) plants was used to study the effect of nucleus/chloroplast interaction on the physiology of the respective cybrid. Percentage of seed germination, response of shoot apices to form adventitious shoots on B5 medium supplemented with 5% liquid coconut endosperm and 2.5 M ... إقراء المزيد