2024-03-28T13:51:03Z
https://ejbo.journals.ekb.eg/?_action=export&rf=summon&issue=5166
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Investigation of Mitodepressive and Clastogenic Potentials of Diatomaceous Earth Based on Plant Bioassay
Shaimaa
Sobieh
The present study evaluated the mitodepressive and clastogenic effects of different concentrations of Mozambique diatomaceous earth (DE) on Vicia faba L. root meristems. The effects of different DE concentrations (10, 30 and 60%) for 3, 6 and 12h have been studied on mitotic process, micronucleus frequency, pollen sterility, some biochemical parameters and ultrastructure of internal organelles. Significant dose and time dependent suppression of MI was observed. Various types of mitotic aberrations were observed in all treatments and spindledisturbance was the most common type induced. The genotoxic effect of DE was monitored by the induction of high ratio of micronucleus and reduction in pollen fertility. As well, DE suspensions caused drastic damages on cellular organelles in dose and time dependent manner. Gene expression was changed as DNA and protein synthesis was inhibited. All present results revealed the predominance clastogenic and genotoxic effect of DE suspension on Vicia faba L,which were concentration and time dependant.
Mozambique diatomaceous earth (DE)
Mitotic arrest
Genotoxic effect
DNA & protein synthesis depression
Ultrastructural aberrations
Vicia faba L
2019
04
01
1
14
https://ejbo.journals.ekb.eg/article_14001_8bb66571018e90437c93f8624cb483f1.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Three New Pottiaceae Records to the Bryoflora of Libya
Mai
Taha
Three taxa of Pottiaceae; Crossidium laevipilum Thér. & Trab., Didymodon umbrosus (Müll.Hal.) R.H.Zander and Tortula brevissima Schiffn. are new records to the moss flora of Libya bringing the number of mosses known from this country to 105 taxa. Furthermore, the present work adds 14 moss taxa to Gharyan area which raises the moss known from it to 27 taxa. Descriptions, illustrations, floristic and distribution remarks are provided for the three new records to Libya.
Pottiaceae
Bryoflora
Libya
Gharyan
New records
2019
04
01
15
28
https://ejbo.journals.ekb.eg/article_14010_4b92e13dfc5e68d1e01db04a80fc7b64.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus
Sarah
Ahmed
Sahar
Tolba
Yehia
Al Zawahry
One hundred and nineteen clinical samples were isolated from patients admitted in different hospitals in El-Sharkia Governorate. Sixty six isolates were confirmed to be S. aureus. Susceptibility to different antimicrobial agents and Minimum inhibitory concentration tests showed that all the isolates were resistant to 𝛽-lactam antibiotics, 77.2% (n= 51) isolateswere methicillin resistant S. aureus MRSA, while almost all the isolates were sensitive to vancomycin and tigecycline. Polymerase chain reaction (PCR) of mecA, encoding methicillin resistance, and blaZ, β-lactamase biosynthetic gene, revealed the coexistence of both genes in 56.8% (n= 29/51) of the isolates. Meanwhile, 11.7% (n= 6/51) of MRSA isolates phenotypically resistant to oxacillin were found to be mecA-. This data support the fact that the expression of bla genes enhanced the phenotypic expression of oxacillin resistance as a result of β-lactamase hyperproduction. On the other hand, 33% of MRSA (n=17/51) were blaZ– suggesting a mutation event in blaZ or the existence of an alternative mechanisms for 𝛽-lactam resistance that may compete with mecA gene.
Staphylococcus aureus
mec A
blaZ
MRSA
MIC- β-lactamase resistant MRSA
2019
04
01
29
38
https://ejbo.journals.ekb.eg/article_14014_bae95b4d9bce94912bdbfb1cd54fbe76.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Effect of Pollution Type on the Phytoplankton Community Structure in Lake Mariut, Egypt
Olfat
Abdel-Hamid
Tarek
Galal
T he effect of water quality on the phytoplankton community was investigated in Mariut wetland, Egypt. Water samples were collected from the lake through five stations representing the four basins of the lake (northeast, northwest, southeast and southwest), in addition to Nubaria canal. Eighty-nine phytoplankton species, dominated with bacillariophytes and cyanophytes, were recorded. The northwest basin had the highest number of phytoplankton followed by the northeast basin, Nubaria canal, and the southeast and southwest basins. Holoplanktons dominated over tycoplanktons, meroplanktonic, and epiphetic algae. The dendrograms resulting from the agglomerative clustering technique based on water characteristics and phytoplankton composition had more or less the same trend. Moreover, the application of principal component analysis indicated that water pH, P, Cd, Zn and HCO3were the most effective variables affecting the distribution of phytoplanktons. Cyanophyteswere highly affected by K and salinity, while bacillariophytes were affected by water pH andPb, euglenophytes by Ca and Mg and chlorophytes by P, Cu and Fe. The predominance ofbacillariophytes in the lake indicates the tolerance of this group to the different pollution types,while cyanophytes prefer fresh water and dominates the least polluted wetlands.
algae
Bioindicators
Community
diatoms
pollution
2019
04
01
39
52
https://ejbo.journals.ekb.eg/article_14017_5a483175778378e0d79be0d71da3f6a3.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Morphology and Stem Anatomy of Chenopodium Species from Egyptian Flora
Ali
Gaafar
Stem anatomy, stomatal types and stomatal index along with morphological characters of six Chenopodium species namely: C. album, C. ficifolium, C. ambrosioides, C. glaucum, C. murale and C. quinoa were investigated by using light microscopy. Two types of stomata were recorded: Anisocytic type commonly recorded in five species, while anomocytic recorded only in C. ambrosioide. Leaf epidermal anatomy revealed great taxononmic value which can be used for the identification of species. Artificial key was provided for the identification of the studied species.
Chenopodium
light microscopy
morphological characters
stem anatomy
Stomatal morphology
2019
04
01
53
58
https://ejbo.journals.ekb.eg/article_15373_7dbb98ab17b6a1bbdfd2c503c8efb9a6.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Genotoxic Effects of Some Plant Oils and Abamectin in Vigna unguiculata L. Stored Seeds as Revealed by the iPBS-DNA Fingerprinting
Hala
Mahfouz
H.
Barakat
R.
Essam
E ssential oils and the bio-insecticides have been utilized to protect the plants aginstdifferent kind of insects. However, it is really improtent to study the side effects of theseessential oils and insecticides on plants. The iPBS technique based on Long Terminal Repeat(LTR) retrotransposons was applied in this study to detect the DNA damage in cowpea seedsexposed to three plant oils of Trigonella foenum-graecum, Panax ginseng, Origanum majoranaand the bio-insecticide abamectin. Different levels of polymorphism ranged from 37.50%polymorphism for primer 2394 to 82.35% polymorphism for primer 2270 with a total averageof 52.00%. Also, decrease in genetic template stability (GTS%) values were recorded withall treatments as compared with the control. The value of Band Sharing Index (BSI) for eachtreatment was calculated and the results showed that mixture 2 (LC20 abamectin + 2LC95ginseng) showed the lowest (BSI) as compared with all treatments. The obtained results,suggested that the assurance should be strongly taken in the consideration for the safety,efficacy, and toxicity of the preparation derived from plants. Furthermore, iPBS assay is apowerful tool for the detection of the genotoxic effects of environmental chemicals and offergreat promise for future especially for the determination of genetic damage following exposureto contaminants.
iPBS technique
plant oils
Cowpea seeds
GTS and BSI
2019
04
01
59
67
https://ejbo.journals.ekb.eg/article_16265_656f1e075e4e336608ccda51967c2618.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Molecular characterization and biocontrol-traits evaluation of Trichoderma virens TVH3 against Fusarium oxysporum, the causal agent of tomato wilt.
Alsayed
Alfiky
Medhat
Eldenary
In atte mpt to screen for new biological control agents (BCA) with high activity against soil-borne fungal pathogens, an isolate of the BCA Trichoderma virens was obtained, identified using molecular techniques and named TVH3. The antagonistic activities ofthis isolate were tested against Fusarium oxysporum, a major soil-borne fungal pathogen of diverse crops. Our results revealed that T. virens TVH3 displayed high antagonistic potential against F. oxysporum via different mechanisms to control its prey, suchmechanisms include competition for the available space and nutrients, mycoparasitism andproduction of antimicrobial secondary metabolites including volatile organic compounds(VOCs). The antifungal soluble metabolites in Trichoderma’s culture filtrate were found tobe thermal-stable and T. virens TVH3 was found to possess high natural immunity againstantimicrobial metabolites in F. oxysporum culture filtrate. In the biocontrol assay, isolateT. virens TVH3 was applied as seed coat on tomato seeds before planting them in heavilyinfested soil with pathogenic strain of F. oxysporum and the obtained results revealed that such seed treatment had significantly reduced wilt signs on plants and provided the seedlings with effective shield against pathogenic infection.
Biocontrol
Trichoderma
Fusarium
Biofungicide
Tomato, Wilt
2019
04
01
68
80
https://ejbo.journals.ekb.eg/article_16427_9fef9a7fd7692c32d2f2234aea56301a.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
In vitro Evaluation of Syzygium aromaticum L. Ethanol Extract as Biocontrol Agent against Postharvest Tomato and Potato Diseases
Walid
Soliman
Mona
El bous
Mohsen
Ibrahim
Heba
El Baz
E thanolic extract of dried flower bud of Syzygium aromaticum L. (clove) was investigated to evaluate its antifungal activity against local fungal isolates causing postharvest infections form potato and tomato. Four fungal isolates; Geotrichum candidum, Alternaria alternata, Fusarium oxysporum and Mucor hiemalis were identified. All fungal isolates were found to be inhibited by the extract; whereas the smallest inhibition zone) of S. aromaticum extract was 2.5% for M. hiemalis, A. alternata, G. candidum and 12.5% for F. oxysporum. Quantitative assessment of phytochemical compounds in clove plant revealed the presence of phenolic acids (20.80%); flavonoids (26.81%); tannins (4.90%), saponins (2.60%), alkaloids (1.60%), total protein (17.83%), total carbohydrate (2.23%) and total oil (0.90%). Biochemical profile was revealed by GC/MS which detect 18 different chemical compounds. The major compounds were eugenol (17.27%), trans-caryophyllene (0.50%), humulene (3.33%), anthracenedione (3.35%), cedran-diol (0.61%), citroflex A (5.45%) and lucenin 2 (8.25%). TLC technique and different solvent systems were employed to select the proper one based on its capacity to isolate the maximum number of fluorescent spots in crude extract.Chloroform-acetone-butanol (CAB) 85:15:20 could efficiently separate three bands (A, B and C). Each detected band was individually screened for its antifungal activity against the isolated fungi. Only band C showed a significant antifungal activity. Mass spectroscopy (MS) was used to investigate characteristics, purity as well as expectation of both chemical formula and molecular weight of the isolated compounds; which finally proved that glucoside β-sitosterol was the main compound represented in fraction -C.
Syzygium aromaticum
Antifungal
post-harvest
secondary metabolites
TLC
GC/MS
2019
04
01
81
94
https://ejbo.journals.ekb.eg/article_16430_3865cbbcd4f64daee097b6a43faef837.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Isolation and Identification of Potent Probiotics with High Lead Removal Capability
Amany
Shaheen
Khaled
El-Baghdady
Abeer
Zakaria
Probiotics play an effective and significant role in human health. The aim of this study was to isolate potential probiotics from Egyptian sources. Among the 14 different bacterial isolates recovered from 8 different sources on Man-Rogosa-Sharp (MRS) agar medium, 5 isolates exhibited tolerance to pH 3 and survived at bile concentration of 0.3% for 3h. The selected isolates were resistant to amikacin, vancomycin, ciprofloxacin and bacitracin. In addition, they showed high antibacterial activity against 7 pathogens. Hydrophobicity usingxylene and toluene showed high hydrophobic property for M isolate with toluene and xylene (80.43±0.95% and 78.2±0.73%, respectively). The potent isolate was identified by 16S rRNA gene as Lactobacillus plantarum strain M (KY508300). This strain was able to remove 71.28 ± 0.4 % of lead (1mg/ml) after 5min. The probiotic strain M showed count stability in yoghurt up to 21 days. The characteristic features of L. plantarum strain M as potent probiotics entitled it to be used in industrial and environmental applications.
probiotics
pH
Antimicrobial
Bile
Hydrophobicity
Lead
2019
04
01
95
105
https://ejbo.journals.ekb.eg/article_16433_85d42516b0427742988a4ce49fe6277c.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Computer-generated Keys to the Flora of Egypt. 9. The Spiny Taxa of Asteraceae
Adel
El-Gazzar
Nahed
Elhusseini
Azza
Khafagi
Nashwa
Mostafa
Manually constructed keys for identification of plants leave much to be desired. Keys to the Asteraceae of Egypt are no exception and depend largely on floral minutiae while vegetative morphology is a much richer source of characters suitable for key construction. Inspection of some 3000 specimens showed that the most obvious feature of the plants is the presence or absence of spines on leaves, leaf axils, stem internodes, margins of stem wings and phyllaries. This feature was selected to divide species of this family into two main groups: spiny and spineless. Nomenclature of all taxa was updated and those with names reduced to synonyms of others were eliminated. This article deals only with the 65 species belonging to 20 genera of the first group. A total of 51 characters describing variation in spine distribution and other characters of vegetative morphology were recorded for each of the 65 spiny species and the key-generating program DELTA was applied to the data matrix. The result is a much improved automated key, a detailed description of every species in terms of the entire set of 51 characters, and the same description but in terms of the serial numbers assigned to these characters and their states.
Asteraceae
DELTA
Egypt
identification
Morphology
Spiny-taxa
2019
04
01
107
138
https://ejbo.journals.ekb.eg/article_16434_0ee0c9aff50a2da96b419cf3d3c7843c.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Accumulation and Distribution of Minerals and Heavy Metals in Sugar Beet and Carrot Plants Grown on Soil Amended with Filter Mud Cake
Fawzy
Salama
Noha
El-Tayeh
Naglaa
Loutfy
Mona
Aboualhamed
Filter mud cake (FMC) collected from Qus sugarcane factory at Qena in Egypt was applied in a pot experiment to investigate the uptake and distribution of certain mineral nutrients and some heavy metals in different organs of both experimental plants. The filter mud cake was mixed with sand at three levels: 10%, 30% and 50% and the sand was used (without FMC) as control. Results showed that amendment the sandy soil with filter mud cake resulted in increasing in K and, Ca contents in both experimental plants. Moreover, Mgcontent had irregular behavior by decrease or increase. Na content- in contrast to Ca and K showed significant decrease of carrot and sugar beet plants. The distribution of Na and K was in another way, and mostly Na accumulated in roots while more K transported into shoots of both plants. Results indicated also that Na/K ratio was higher in plant roots than in shoots. Data revealed that FMC stimulated the accumulation of Cl, PO4 and SO4 content in two tested plants as compared with control. Mg, Ca, Cl, SO4 and PO4 distributed in shoots and roots with significant change from the roots toward the shoots. Generally, FMC treatments increased Zn, Cu, Pb and Cd accumulation in carrot and sugar beet plants compared to control. Correlation analysis between the contents of heavy metals in both organs of carrot and sugar beet plants andthat in the sand-FMC mixture showed different relationships.
Sugar beet
Carrot
Filter mud cake
Heavy metals
minerals
2019
04
01
139
149
https://ejbo.journals.ekb.eg/article_16504_2342ae66680c4f24391f5afb34fce0f0.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Cadmium Biosorption from Wastewater by Yarrowia lipolytica AUMC 9256
Manal
El-Sayed
The present study aimed to assess the biosorption capacity of live, autoclaved and dried biomass of Yarrowia lipolytica AUMC 9256 for cadmium (Cd(II)). Minimum inhibitory concentration 500mg/L proved great tolerance of Y. lipolytica AUMC 9256 to Cd(II). The time course growth in the presence of different concentrations of Cd(II) was studied. For live, autoclaved and dried biomass, maximum uptake capacities accomplished at pH 5.0, initial metal ion concentration 400mg/L, biomass dosage 1g/L, and contact time 20min for autoclaved and dried biomass and 240min for live cells. The potential of Y. lipolytica to produce cadmium nanoparticles was determined by UV-Visible spectroscopy measurements and transmission electron microscopy examinations. Moreover, to identify the possible mechanisms of Cd(II) uptake, TEM examinations, Fourier Transform Infrared spectroscopy, Energy dispersive X-ray microanalysis, and X-ray powder diffraction analyses were carried out. The potential implementation of dried Y. lipolytica biosorbent for heavy metal removal from different water samples was successfully accomplished using the multistage microcolumn technique. Accordingly, Y. lipolytica AUMC 9256 can be considered as a very promising potential tobioremediate Cd(II) ions and biosynthesis of Cd NPs.
Yarrowia lipolytica AUMC 9256
cadmium
Biosorption
Mechanism
Nanoparticles
2019
04
01
151
169
https://ejbo.journals.ekb.eg/article_17772_44e05f0bfc1fb25d375e7498d0720f5c.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Effect of Rice Straw Application on Water Quality and Microalgal Flora in Fish Ponds
Hamed
Eladel
Reham
Abd-Elhay
Doaa
Anees
The present experiment was conducted to assess the effects of decomposing rice straw on algal flora as well as physical, chemical, and biological-parameters of 9 earthen fish ponds of 2100m3 for each with one-meter average depth. It was conducted for 6 months using three treatments. Each pond was stocked with 6000 fish fries of Nile tilapia (Oreochromis niloticus). Results showed that water quality decreased with increased loading rates of rice straw. Most of water quality parameters including EC, TDS, total alkalinity, total phosphorus, NO3, NO2, chlorophyll a, and pH were significantly lower in rice straw treatments than control. Total ammonia, Secchi disc visibility and orthophosphate were significantly higher with increase rice straw loading than control. Cyanophyceae constituted the dominant algal group at the initial phase at all examined ponds. This dominance remained stable in control ponds by the end of experiment. In contrast, in the final stage of the experiment Chlorophyceae and Bacillariophyceae dominate in T2 and T3 treatments compared with control. The results of this work illustrated that the decrease of algal count was related to action of allelochemicals discharged from rice straw aqueous extract leading to suppress growth of some algal species. Hence, this technique is a way to reduce the cost and reduce the use of herbicides, by providing natural compounds that can be obtained from agricultural waste.
rice straw
water quality
Microalgae flora
Fish pond
2019
04
01
171
184
https://ejbo.journals.ekb.eg/article_17773_365c995a212b618119e4957670f9b5f7.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Physiological Effects of Spirulina platensis in Salt Stressed Vicia faba L. Plants
Eman
Selem
Salinity is one of the most important problems in Egypt. Soil salinity decreases growth, photosynthetic activity, and results in nutrient imbalance in plants. This study evaluated the efficacy of the foliar applied Spirulina platensis (100mg/L) in reducing salinity effects in Vicia faba L. plants. The treatments are, T1 (control), T2 (salinity, 135mM from NaCl, equivalent to 13dS m−1), T3 (Spirulina platensis, 100mg/L), and T4 (salinity, 135mM+ Spirulina platensis, 100mg/L). Salinity decreased significantly chlorophyll a+b, carotenoids, weights of 100 seed, photosynthetic activity (14CO2 fixation), transpiration rate , total protein and (N, P and K). Application of T4 improved the above parameters as compared to salt-stressed plants. Salinity increased significantly the SOD, POD, CAT, GPX, MDA, free proline, total phenol and Na+ andCl− as compared to the control plants. However, T4 treatment decreased the activity of the above parameters as compared to salt-stressed plants. Foliar applied Spirulina platensis ameliorated adverse effects of salinity by enhancing total protein level, N, P and K and photosynthetic activity (14CO2 assimilation). This first attempt to evaluate the potential of Spirulina platensis as growth enhancer under salt-stressed Vicia faba indicated that exogenously applied Spirulina platensis (100mg/L) provided more benefit against salinity stress.
Vicia faba L
Photosynthetic activity (14CO2 fixation)
Spirulina platensis
Salt stressed
2019
04
01
185
194
https://ejbo.journals.ekb.eg/article_17900_bdc2f75ab9f7e9f17807ce0f8415320a.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Efficacy of Thermophilic Soil-Isolated Paenibacillus sp. NBR10 as a Chitinolytic and Biocontrol Bacterium- In vitro Study
Mohamed
El-Sayed
Olfat
Nassar
Heba
Nasr
Abd El-Nasser
Kobisi
Among microbial enzymes, chitinases received increased attentions due to their wide applications especially in agriculture sector for biocontrol of fungal phytopathogens. The growing interest in chitinases with thermostability nature, forced many researchers to isolate and characterize novel chitinase producing-bacteriafrom extreme environments. The present study describe characterization of thermostable chitinase produced by thermophilic soil-isolated bacterial strain NBR10 from Rafha governorate, Saudi Arabia. Chitinase producing NBR10 strain was identified as Paenibacillus sp. according to the traditional methods of morphological, biochemical and physiological characteristics coupling with sequencing of 16S rRNA (GenBank accession number KT957624.1). The isolated strain was found to have a potent antifungal against three of the phytopathogenic fungi Fusarium oxysporum, Alternaria burnsii and Rhizoctonia solani with percent of growth inhibition 52.5 75.0 and 85.71%, respectively. Chitinase obtained from Paenibacillus sp. NBR10 showed activity at ranges of temperature (30–90°C) and pH (4–9), showing optimum activity at 55°C and pH 7.0, respectively. Also, it exhibited high thermostability at higher temperatures, where 90% of its activity is retained at 65°C for 36h. The promising chitinolytic and antifungal activity of locally isolated Paenibacillus sp. NBR10, candidate this strain to be used as a potential biological control agent.
Soil
Paenibacillus sp. NBR10
Thermostable chitinase
Antifungal
biological control
2019
04
01
195
208
https://ejbo.journals.ekb.eg/article_19911_e3f3fe9d2c5d5f2fcde56a60d8f0408e.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Computer-Generated Keys to the Flora of Egypt. 8. The Lamiaceae
Adel
El-Gazzar
Albaraa
El-Saeid
Adel
Khattab
Alaa
Elkady
Abbas
ElGhamery
Manually-constructed keys to many groups of the Egyptian flora are in urgent need of improvement and updating. To construct a conventional substitute of the key to representatives of the Lamiaceae, a data matrix was compiled to include 48 characters recorded for each of the 52 species (with three subspecies and onevariety) belonging to 24 genera which represent this family in the flora of Egypt. The 48 characters were accurately defined to cover as much of the easily observable aspects of vegetative and floral variation in the plants as possible. The data matrix was analyzed using the key-generating package of programs DELTA. The analysis produced a conventional key with a detailed description of every species in terms of the 48 characters. The key is decidedly a marked improvement over its predecessors in that it is strictly comparative. Updating the nomenclature of the plants led to the first recording of the genus Thymbra in the flora of Egypt.
Conventional key
DELTA
Egypt
Flora
Lamiaceae
Thymbra
2019
04
01
209
232
https://ejbo.journals.ekb.eg/article_18326_8110d93d03ca981c9938e76666618d8c.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Clinopodium serpyllifolium subsp. barbatum (Lamiaceae) and Datura ferox (Solanaceae): New Records For The Flora of Egypt
Sami
Rabei
Abdel-Hamid
Khedr
Ibrahim
El Gamal
Clinopodium serpyllifolium subsp. barbatum (Lamiaceae) and <i> Datura ferox (Solanaceae) have been recorded for the first time from Egypt. Both taxa were found in the mountainous region of Saint Katherine Protected Area, South Sinai. Morphological description and photos were given. Herbarium voucher was kept at related Herbaria.
Clinopodium serpyllifolium
Datura ferox
Egypt
new record
Morphology
Saint Katherine Protectorate
2019
04
01
233
239
https://ejbo.journals.ekb.eg/article_19912_2e7ba39449e59b0c753424d9defe0ef4.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Dynamic Interaction between Toc159 and Blue Light Receptors at the Chloroplast Outer Envelope of Pisum sativum (L.)
Heba
Hamdy
Mohamed
Ibrahim
Physiological significance of Pisum sativum TOC GTPases protein phosphoryation has linked the regulation of protein import into chloroplast with the environmental changes. Phototropin 2 is localized at outer membrane of chloroplast. It was crucial to study the relation between Phot2 localization at chloroplast membrane and phosphorylation of TOC GTPases under blue light intensities. Kinase activity of Phot2 towards TOC GTPases was characterized in outer membrane of Pisum sativum. TOC GTPases were specifically and differentially phosphorylated under diffrent light quality and intensities. Gene chip analysis was performed to correlate between expression of TOC complex subunits and blue light receptors genes using A. thaliana. It was found that transcript level of AtToc33 was the highest observed expression with AtToc159 and AtToc75-III. Also, 26 phototropins and photropin-like genes were identified. Coexpression gene netweork of AtPhot2 has revealed a close connection with TPR-containing protein (At1g01320) and chloroplast Toc159 (AT4G15810). Co-immunoprecipitaion assay has evidenced that no intercation was detected between AtPhot2-KD and PsToc34. However, AtPhot2-KD was found to interact with AtToc159. Chloroplast outer and inner envelopes purified from A. thaliana knockout line of Phot2 has phosphorylated AtToc33 and AtToc86/159 in vitro. Hereby, Phot2 is not the specific protein kinase for TOC GTPases. Hence, it was suggested that certain signal cascades may directly or indirectly link phosphorylation of TOC GTPases, protein levels of PHOT-LIKE proteins and irradiation conditions. Therefore, TOC GTPases phosphorylation might be an external regulatory signal to regulate preproteins import into chloroplasts in response to light changes or as a signal of chloroplast biogenesis.
Pisum sativum L
TOC complex
Toc159 receptor protein
Protein phosphorylation
Phototropin2
2019
04
01
241
253
https://ejbo.journals.ekb.eg/article_23474_79fe70515fc85686fe8d1d40afb44b01.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Stabilization of Trimeric PSI within Thermosynechococcus elongatus via Chlorophyll a and Carotenoids Located in Monomer- Monomer Interface Area
Eithar
El-Mohsnawy
Monomeric PSI is found within thermophilic cyanobacteria, i.e., Thermosynechococcus elongatus either in case of iron deficiency or deletion of PsaL subunit. Previous investigations pointed to the role of PsaL in oligomerization of monomeric complexes. Successful isolation of monomeric PSI was achieved only via salt treatment of thylakoid membrane at high temperature (50°C). Here, monomeric PSI was obtained through splitting the purified trimeric PSI in vitro. Selective elimination of carotenoids and Chlorophyll a located in monomer-monemer interface area was performed using a mixture of hexane with different organic solvents.Hexane-dimethyl sulfoxide mixture was considered the best organic solvent for removal the interface carotenoids and chlorophyll a, where it splatted trimeric PSI completely. Also, the role of carotenoids and chlorophyll a on stabilization of trimeric PSI was proven by sucrose density gradient and blue native gel. 77K spectroscopical emission fluorescence measurements of investigated PSI showed blue shift peaks due to monemerization as well as formation of uncoupled chlorophylls. The efficiency of organic solvents on removing carotenoids molecules was higher than chlorophyll molecules, where about 12/96 chlorophyll molecules and 12/22 carotenoids molecules have been eliminated in case of complete splitting of trimeric PSI.
Trimeric Photosystem I (PSI)
Thermosynechococcus elongatus
Chlorophyll a
Carotenoids
2019
04
01
255
267
https://ejbo.journals.ekb.eg/article_25539_ef203756954bc0840aa48fdba93ec975.pdf
Egyptian Journal of Botany
Egypt. J. Bot.
0375-9237
0375-9237
2019
59
1
Salt Stress Induces Changes in Genetic Composition, Proline Content and Subcellular Organization in Potato ( Solanum tuberosum L.)
Shaimaa
Sobieh
Thoria
Rashad
Zakia
Adam
Ayman
Elfiki
Amal
Awad
Several abiotic stresses including salinity impact plant growth and reduce the productivity of many plants and field crops. Plantlets produced in vitro by tissue culture technique offer a direct and fast approach to investigate the mechanism of stress adaptation. The present study estimated the survival percentage of two potato (Solanum tuberosum L.) cultivars (Spunta and Valor) under salt stress as abiotic stresses. Some biochemical alterations and ultrastructural responses of plantlets were examined. Moreover, genetic diversity was also studied using RAPD technique. The results showed that, with the increase of external stress there was a significant decrease in the survival percentage, significant accumulation of osmoprotectants (proline) and induction of DNA damages. Furthermore, there were closing of stomatal apertures, changesin chloroplast ultrastructure and cell intercellular spaces markedly decreased. Additionally,high salt stress (150 and 200mM NaCl) caused complete inhibition of plantlet growth. Thepresent work provides insight view for the adaptation of potato plantlets to salt stress throughaccumulating of osmoprotectants and change in molecular and ultrastructure traits.
Potato plantlets
Saline stress
morphological characters
DNA Polymorphism
Ultrastructure changes
2019
04
01
269
282
https://ejbo.journals.ekb.eg/article_23475_18183088b64bf6c1b53ab1c25760c214.pdf