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Influence of Different Nitrogen Sources on Growth and Pathogenic Capability of Rhizoctonia solani Causing Root Rot of Faba Bean
2019
Maha Mohamed
ABSTRACT The effect of different nitrogen sources (glucosamine sulfate, ammonium sulfate, aspartic acid, phenylalanine and peptone) in comparison to sodium nitrate, the major nitrogen compound in basal agar Czapek’s synthetic medium growth were studied on the linear growth of Rhizoctonia solani and its pathogenicity on faba bean germinated seeds. Ammonium sulfate exhibited faster liner growth and showed the same effect as the basal medium with sodium nitrate while, glucosamine sulfate showed less growth rate compared with sodium nitrate. Glucosamine sulfate and ammonium sulfate showed significant reduction in number of infection cushions which led to significant decrease of disease index in vitro. Our results showed strongly significant positive correlations between disease index and both of diameters of hyphae and number of infection cushions while, very weak correlation coefficient was found between disease index and linear growth of R. solani. Under greenhouse conditions, glucosamine sulfate or peptone as a sole nitrogen sources in food requirements of Rhizoctonia solani inoculum depressed the virulence of the fungus. The effect of different amounts of glucosamine sulfate was determined on fungal growth rate, infection cushions, disease index in vitro and polyphenol oxidase activity. Increasing amount of glucosamine sulfate showed significantly reduction of growth rate in comparison to the basal medium with sodium nitrate. All seeds subjected to R. solani grown on different amount of glucosamine sulfate showed the lower number of infection cushions, disease index and polyphenol oxidase activity compared with sodium nitrate. Under greenhouse conditions, disease index showed significantly decreased effect when glucosamine sulfate used as soil applications and showed better effect on shoot weight and root weight compared with control plants treated with sodium nitrate. Our study proposes that glucosamine sulfate may acts as controlling factor of pathogenicity genes of R. solani. Key words: Rhizoctonia solani, faba bean, Vicia faba, nitrogen sources, glucosamine sulfate, pathogenicity.
Show more [+] Less [-]Isolation and identification of halophilic bacteria producing exopolysaccharides from whey and milk permeate
2019
Amal Hegazy | Mohamed El-Nawawy | Ali Ali | Yehia El-Samragy
The aim of this research was to utilization of the salt whey and milk permeate to produce exopolysaccharides (EPSs). Where cheese whey is simultaneously an effluent with nutritional value and a strong organic and saline content. However, it is drained in the sewers, the EPSs are highly heterogeneous polymers produced by different species of bacteria and have recently been attracting considerable attention from biotechnologists because of their potential applications in many fields. Thus, we have isolated some halophilic bacteria that showed the ability to produce EPS from whey and milk permeate. A total of 46 strains of moderately halophilic bacteria were isolated from two types of samples. The first type was dairy samples (Baramily cheese whey and mish cheese), while the second type was water samples (salty lake water and its sediments) of Wadi El-Natrun Valley (lakes Hamra, UmRisha, and Baida), Beheira Governorate, Egypt. From isolated strains there are twelve strains were having the ability to produce exopolysaccharides but only seven strains can produce EPS from whey and milk permeate. The growth conditions i.e. concentrations of NaCl, pH value and different incubation temperature, of isolates were determined. The effect of these conditions on the production of EPS was investigated. The obtained results indicated that the optimum conditions for the production of EPS by these strains were 10 % NaCl, pH 7 and the optimum incubation temperature was 37°C. Three strains showed the highest production of exopolysaccharides. These strains were identified using two methods the first method was biology system and the second one was 16S rRNA sequence analysis method. It could be identified as Alteribacillus bidgolensis and Bacillus licheniformis. Alteribacillus bidgolensis (strain P4B) produced the highest amount of EPS (52 g/L) from whey followed by Bacillus licheniformis (DSM 13) (42 g/L), while the highest amount of EPS produced from milk permeate was (43 g/L) by Alteribacillus bidgolensis (strain P4B) followed by Bacillus licheniformis (DSM 13) (36 g/L).
Show more [+] Less [-]Interaction between Biotic and Abiotic Agents to Control of Potato Bacterial Wilt Disease
2019
Hanan Abdrabouh | Afaf Zein El-abdeen | Nagy Abdel-Ghafar
Bacterial wilt disease caused by Ralstonia solanacearum (Smith) Yabuuchi, et al. (1995) is one of the most important bacterial diseases over the world. This study was planned to control the disease using interaction between biotic and abiotic agents, under greenhouse experiment. In vitro, tested bactericides (gentamycin, ceflaxcin and copper sulphate) were decreased growth of R. solanacerum compared with control treatment. Copper sulphate was the most effective compared with ceflaxcin and gentamycin, but ceflaxcin was moderately effective and gentamycin was less effective against the pathogen. Inhibition zone diameter was increased with increasing concentrations of tested bactericides. Application of different bio-agent isolates (Pseudomonas fluorescence, Bacillus subtitlis, Bacillus megaterium and Serratia mareacescne) were reduced the growth of the pathogen compared with control treatment. B. subtilis isolate was the most effective, but isolates of Ps. fluorescens and B. megaterium were moderately effective and S. marescences isolate was less effective against the pathogen. Greenhouse experiments, disease severity were decreased and potato yield were increased with interaction between bio-agents (Bacillus subtilis, and Pseudomonas fluorescence isolates) and bactericides (gentamycin and ceflaxcin), or bio-agents and resistance inducers factors (salicylic acid and jasmonic acid) or bactericides and resistance inducers factors compared with control treatment. However, interaction between bio-agents as tuber treatment and bactericides as soil drench treatment or interactions between bactericides as soil drench treatment and resistance inducers as foliar treatment were the most effective against the disease and the yield. But, interactions between bio-agents as soil drench treatment and resistance inducers as foliar treatment were moderately effective to control the disease and the yield. But, interaction between ceflaxcin as bactericide and Ps. fluorescens isolate as bio-agent or salicylic acid as resistance inducer were the most effective on disease severity and the yield compared with other treatments, but interaction between B. subtilis isolate as bio-agent and jasmonic acid as resistance inducer were less effective compared with other treatment.
Show more [+] Less [-]GROWTH AND PRODUCTIVITY OF EGGPLANT AS AFFECTED BY PINK PIGMENTED FACULTATIVE METHYLOTROPHIC BACTERIA
2019
H. Abd El-Salam | A. A. | H. Abd El-Gawad | A. Abdelhafez
The present study was suggested as an attempt to investigate the effects of Pink Pigmented Facultative Methylotrophic Bacteria (PPFM) dipping and foliar spray on vegetative growth and yield of eggplant (Solanum melongena L.). Field experiments were carried out during the summer seasons of 2014 and 2015 at the Experimental Farm, Faculty of Agriculture, Ain Shams University. The vegetative growth of eggplant responded positively to dipping seedlings in PPFM which gave the highest values of growth parameters, i.e. number of leaves per plant, leaf area, nitrogen & potassium concentration in leaf and total protein in fruit, in the two seasons as compared with control (dipping in water). The application of PPFM as foliar spray, increased significantly plant growth (plant length, leaf number, potassium concentration in leaf, vitamin "C" in fruit and total yield per plant) in the two seasons as compared with the other studied foliar application treatments. The interaction between dipping seedlings in PPFM and PPFM foliar spray with all concentrations gave synergistic effects on growth parameters and yield components of eggplant, during the two growing seasons as compared with either individual foliar application or control plants.
Show more [+] Less [-]OPTIMUM CROPPING STRUCTURE OF DAKAHLIA GOVERNORATE
2019
T. Al-Zahaf | M. Rajab
It is the correct cropping structure that achieves the compatibility between more than one goal to reach the most efficient cropping structure in achieving and rationalizing water consumption and low use in the context of a set of constraints and determinants of productivity. In order to increase farm income and provide a large amount of irrigation water to benefit from the surplus In horizontal expansion. The model of the analysis of the agricultural structure in Dakahlia governorate included 18 crops through five different models. The first model (alternative) achieved this total yield of 6.780 billion pounds, more than the equivalent of 116 million pounds. Of the proposed model is less than its equivalent in the prevailing crop structure of 81 million m3 as a result of the increase in the area of some of the crops grown from their counterparts in the dominant structure. In accordance with Ministerial Decision No. 28 of 2018 issued by the Minister of Irrigation published in Al-Ahram newspaper on 8/3/2018, the year 142 - No. 47939, reducing the area of rice in Dakahlia governorate by 45%, four other models were reached.
Show more [+] Less [-]EFFECT OF FOLIAR APPLICATION WITH ALGAE AND MORINGA LEAVES EXTRACTS ON VEGETATIVE GROWTH, LEAF MINERAL CONTENTS, YIELD AND CHEMICAL FRUIT QUALITY OF PICUAL OLIVE TREES
2019
A. Hassan | N. Abd-Alhamid | Rawheya Aly | H. Hassan
This study was carried out during 2017 and 2018 seasons on adult Picual olive cv. (8 years old) in a private orchard located at Cairo Ismailia Desert Road, (about 80 Km from Cairo), Ismailia Governorate, Egypt. Trees are grown in sandy soil, under drip irrigation system, uniform in shape and received the common horticultural practices, therefore, this work aims to study the effect of spraying different concentrations and dates spray of algae and moringa leaf extract (MLE) for tow times on the vegetative growth, leaf mineral contents, yield and fruit chemical properties of Picual olive trees. Results indicated that all different spraying treatments of algae and moringa extract at different spraying dates had a positive effect on vegetative growth, leaf mineral contents, fruit set, yield and fruit chemical properties in comparison with the control. Treatments of algae extract at 0.4% + moringa leaves extract at 2% and algae extract at 0.4% + moringa leaves extract at 4% were the most effective treatments to increase vegetative growth, improve leaf mineral content, fruit set, yield and oil content. Thus, these treatments can be recommended for commercial use under similar conditions
Show more [+] Less [-]DEVELOPMENT OF IN VITRO SOMACLONAL VARIATION FOR PELARGONIUM GRAVEOLENS L’HERIT, AIT
2019
Rasha Hariedy | M. Rashed | Mahassen Sidky
In vitro somaclonal variation via callus is considered as one of the most effective tool for improvement of vegetative propagated crops. Different combinations of cytokinine (BA) and auxine (NAA) were used to induce somaclonal variation from leaf explants of the Egyptian geranium cultivar, Pelargonium graveolens L’Herit, Ait. El Qanater El khayria cv.8. Callus induction and regenerated shoots from callus were evaluated; 2.5 mg/L BA and 0.5 mg/L NAA was the optimal for callus induction and number of regenerated shoots. The obtained plantlets were acclimatized under glasshouse conditions with 80% to 90% survival and were transferred to the open field. The evaluation of growth traits and oil analysis were done for the new 13 clones compared with the mother plant in randomized block design for two successive seasons. Characterization of these new clones for morphological traits and essential oil yield and quality demonstrated the induction of variability in negative and positive directions in some characteristics in comparison with the mother plant. Clone no.7 was the superior clone in herb 2264.7 & 2357.3 g/plant and oil yield 2.436 & 3.065 ml/plant in first and second season, respectively, than the mother plant and other new clones with acceptable content of citronellol 25.63% and geraniol 26.52% as a parameter for volatile oil quality. The genetic variation of the new geranium clones were tested using SRAP technique based on PCR, the polymorphism was detected using 16 pairs of SRAP primers in combinations as forward and reverse. The genetic differences between new clones and the mother plant were ascertained with SRAP primer pair (me2 em4); a unique profile for clone no.7 was detected in SRAP analysis. The similarity percentage varied between 66.7% to 100% homologies among the new clones and their mother plant. The presence of genetic variation between new clones and the mother plant proved that the calliclones were somaclonal mutants, and the geranium cultivar, El Qanater El khayria cv.8, was improved for high yield in herb and essential oil.
Show more [+] Less [-]ANALYSIS OF EGYPTIAN AGRICULTURAL FOREIGN TRADE WITH THE COUNTRIES OF THE EURO - ASIAN UNION
2019
M. Salem | A. Omairi | A. Abdelmaqsoud | Salwa Abd ELMonem
The study aims at identifying the analysis of the Egyptian agricultural foreign trade with the countries of the Euro-Asian Union. The study problem , its objectives and the research method Where identified in the study. Where , there is a lack of information on the expected results or the role that the proposed free trade agreement between Egypt and the Euro-Asian Union could play and the requirements for maximizing the positive results and minimizing the negative consequences if this agreement is signed. Therefore, the research aims to identify the positive and negative results on the Egyptian economy under the proposed agreement, which contributes to reducing the negatives and supporting the positive factors to achieve effective decision-making. The study included four chapters. First, identifying the stages of economic integration. The second chapter was studying the economic interrelationships between the Russian Federation, Egypt, Belarus, Armenia and Kazakhstan, and the third chapter was the identification of commodity trade relations between Egypt and Eurasian countries during the period 2001-2017 through exports and imports between Egypt and the countries of the Euro-Asian Union The most important trading partner of Egypt among these countries is the Russian Federation, where the value of trade exchange between the two countries in 2017 to more than 4 billion dollars, including 3.6 billion imports to Egypt and 0.5 billion exports from Egypt to Russia, The fourth chapter was the use of trade indicators to reveal trade opportunities with the countries of the Euro-Asian Customs Union. Three indicators were used: 1- Conditions of trade, 2- Agricultural trade compatibility, 3- Price competitiveness, The tendency of the terms of exchange for Egypt in many commodities of vegetables and fruits in the studied markets and the most important Russian market and it shows the agricultural trade compatibility of these commodities and the advantage of some Egyptian commodities such as oranges, potatoes and grapes have a significant competitive advantage in the Russian market with great importance. The research included several recommendations, including the promotion of intraagricultural trade between Egypt and the EuroAsian countries through preferential agreements, especially with Russia, Armenia and Kazakhstan.
Show more [+] Less [-]COMPARATIVE STUDIES ON SOME PRODUCTIVE TRAITS AND GENETIC DIVERSITY OF TWO LOCAL STRAINS OF DUCKS: SUDANI AND DOMYATI
2019
Lamiaa Radwan | H. Madian | M. Mahrous | Y. Badaw | A. Zein El-Dein
The present study aimed to investigate the Genetic Diversity and productive Performance for Some Duck Local strains (sudani and domiaty) using Microsatellite genotyping analysis. From the hatched duck chicks, fifty day old ones were taken at random from each strain and reared under the same environmental, managerial and hygienic conditions from one day old until they aged 12 weeks (marketing age). The comparison was held between the two local duck strains for the following traits: Body weight and body measurements measured biweekly from day old until 12 weeks (pooled sex). Body measurements (shank length, keel length and body circumference) measured at 4,8,12 weeks of age for each strain. All chicks provided reared on floor pens, feed and water were provided ad-libitum all ducks chicks fed on two types of rations: A starter ration (from 0-4wks) and A finisher one (from 5-12 wks). The results indicated that There were significant differences in Body weight at all studied ages between Sudani and Domiaty strains (except at 2, 6 wks.) in hatching the average body weight of the Sudanese strain was 40.80 g however it was 34.12 g for the domyati strain, At 4 weeks age, the average body weight of Sudanese strain was 617.21g while it was 446.38g for the domyati strain, At 8 weeks age, the average body weight of Sudanese strain was1490.90g since it was 1235.98g for the domyati strain and At 12 weeks age, the average body weight of Sudanese strain was 2211.0g while was 1691.88g for the domyati strain. Also Body measurements of duck during early periods of growth (aged 4, 8 and 12 weeks) was At 4 wks age there were no significant differences between the two strains, At the age of 8 wks, the same trend was observed concerning the absence of the significant differences between strains and At the age of 12 wks, there were significant differences between the two strains of the breast circumference only where the superiority was recorded for the domyati strain, This may be reflected the genetic differences between the two strains. The results appeared that the PIC (polymorphic information content) of most microsatellite sites was lower than 0.5. This means that the selected microsatellite loci had a1ow diversity and can reflect the genetic relationship among Sudani and Domiaty populations. This assured that both sudani and domyati populations could be considered as a near populations on a molecular level.
Show more [+] Less [-]ASSESSMENT OF GENOTОXIC EFFECTS OF SOME FOOD ADDITIVES ON SOME HUMAN CANCER CELLS
2019
Shimaa Rashad | F. Abdel-Tawab | Eman Fahmy | A. Attallah | Ekram Ahmed | A. Haggran
Some food additives commonly used by humans have been recently proved to be mutagenic. It is of significant importance to evaluate their genotoxic effects, since they are frequently consumed by humans in their daily meals. In this study, we investigated the effects of monosodium glutamate (MSG), sodium benzoate (SB) and saffron on human cell lines; lung cancer (A549), breast cancer (MCF7), colon cancer (Caco-3) and normal lung (Wi38) cell line as control. Cytotoxicity of food additives was screened on multiple cell lines and examined by NR assay (Neutral Red assay). The present study focused on the cytotoxic activity of the food additives and its possible underlying mechanisms. The results showed that food additives; MSG, SB and saffron induced profound cytotoxicity in cancer cells of human colon cancer (Caco-3) (IC50 = 33.92, 15.01, 3.98 μg/ml), human breast cancer (MCF7) (IC50 = 12.79, 0.378, 10.73 μg/ml), human lung cancer cell line (A549) (IC50 = 27.37, 0.45, 2.46 μg/ml), respectively. Moreover, food additives exhibited cytotoxic activity on normal lung cell lines (Wi38) (IC50 = 4.25, 0.733, 18.14 μg/ml). These data indicated that food additives decreased cell viability in malignant and nonmalignant cells as well as confirmed the occurrence of their cytotoxic effects.
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