خيارات البحث
النتائج 841 - 850 من 1,443
Using Probiotic Bacteria for Soymilk Fermentation
2021
Abdallah Gad | Mona Orabi | Dina Abdelghani | Khadiga Aboutaleb | Shimaa amin
Five probiotic bacterial strains (Lactobacillus plantarumATCC 14917,Lactobacillus caseiDSM 20011, Lactobacillus acidophilus ATCC20552, Lactococcus thermophilus DSM 20259,and Bifidobacterium longum B41409) were used as monoculture, and combined with them as co-cultures for the fermentation of soymilk. The total number is 20 co-cultures, separated similarly into two parts, the first half of each co-culture consisted of two strains, and the second half of each co-culture consists of three strains. The findings revealed that these cultures were capable of fermenting soymilk at only 8 h with a pH drop of between 4.42 and 4.89. Among 25 cultures, eight cultures (3 monoculture of L. plantarumATCC 14917 (C1),Lc. thermophilusDSM 20259 (C4), and B. longum B41409 (C5) and co-cultures of two strains L. plantarum ATCC 14917+ Lc. thermophiles DSM 20259 (C8) and of three strains L. plantarum ATCC 14917 + Lc. thermophilus DSM 20259 + B. longum B41409 (C18), L. plantarum ATCC 14917+ L. caseiDSM 20011+ Lc. thermophilus DSM 20259 (C19), L. caseiDSM 20011+ L. acidophilus ATCC20552+ Lc. thermophilus DSM 20259 (C22), and L. acidophilus ATCC20552+ Lc. thermophilus DSM 20259 + B. longum B41409 (C25)) which recorded the greatest significant viability of bacterial cells, titratable acidity, total organic acids (lactic, acetic, and propionic acids) contented, and pH in fermented soymilk ranged from 9.26 to 9.98 Log CFU/mL, 3.06 to 3.32 %, 19.90 to 18.40 g/L (lactic acid), 13.30 to 12.30 g/L (acetic acid), and 16.35 to15.00 g/L (propionic acid), and 4.38 to 4.62. The soy yogurt produced from the selected fermentation of soymilk was more preferred in the chemical composition of protein, carbohydrate, and fat contents than non-fermented soymilk.So the results show that the integrative use of probiotics may achieve the nutritional value of soymilk after fermentation had been improved by probiotic strains, therefore, making it a more health-beneficial functional food.
اظهر المزيد [+] اقل [-]Evaluation of Different Control Methods on the Rust Flour Beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)
2021
Sara El-Deeb | Maha El-Ghannam | Pansea Azzam
The presented study aimed to evaluate the different control methods of the rusty flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). The experi-ments were conducted to evaluate the effi-ciency of a chemical pesticide (Mala-thion), biopesticide (Tracer 24% SC), plant oil (Lemongrass oil), plant extraction (Ac-etone extracts from Rosemary), powder (Diatomaceous earth) and modified At-mosphere (argon gas). Mortality percent-age increased with increase of exposure times at all tested concentrations. The tox-icity effect of different treatments against adults of T. castaneum at the LC50 after 7 days post-treatment at 30±1°C could be ar-ranged in descending order as follows: Malathion, Tracer 24% and lemongrass oil, while, acetone extracts from Rosemary and diatomaceous earth (DE) were the least effective. The LT50 values against the adult stage of T. castaneum were 19.99, 2.33 and 4.86 hr. for Argon 100, 80 and 60%, respectively. In order to avoid the disadvantages of using chemical insecti-cides such as malathion, it is recommended to use other more safe control methods for the environment as Tracer 24% or lemongrass oil or Argon gas.
اظهر المزيد [+] اقل [-]Nitrogen Nutrition and Adaptation of Halophyte Chenopodium quinoa to Salt Stress
2021
Karema Tarek | Ibrahim Alshamy | Sayed Hussin | Sayed Eisa
There is little evidence that the nitrogen nu-trition supply at rates above or less than what is considered optimal in non-saline conditions improves growth and yield of halophyte crop cultivated under salt stress. Therefore, hypoth-esize of the present work was to find out the magnitude to which N could restore the harm-ful effects of salt stress on quinoa plants. A pot experiment was performed in greenhouse con-ditions to evaluate quinoa's response grown under water salinity treatments (0.0 & 200 mM NaCl) when nitrogen nutrition rates were limiting (50ppm), adequate (250 ppm), and ex-cess (450 ppm) to guide proper application rate of nitrogen fertilizer under salinity stress. The results indicated that, salinity caused a signifi-cant decrease in the vegetative growth of the plant. Consequently, all vegetative measure-ments were negatively affected. As a result, the seed yield decreased to more than 50%. The application of a moderate level of nitrogen (250 ppm) caused a significant ameliorative effect on seed yield by 126% under non saline conditions and 34.5 % under saline conditions compared to the low nitrogen level. The results did not improve any further with the applica-tion of a higher level of nitrogen. These results indicate that applying (N) in adequate may im-prove most traits and prove to be a physiolog-ical treatment to increase resistance against the negative effects of salt stress in quinoa.
اظهر المزيد [+] اقل [-]Foliar Fertilization of Different Species of Mulberry Trees and Its Impact on Silkworm Bombyx mori Productivity from Cocoons and Eggs
2021
sawsan abdelmegeed
Rearing mulberry silkworm was found to be dependent on leaves quality of mulberry trees, larvae of mulberry silkworm fed on two species of mulberry trees Morus alba and Mo-rus nigra were treated with foliar fertilizer (Basfoliar 20-19-19 SP contains 20% N, 19% P2O5, 19% K2O, 5% NO3, 3.6% NH4 and 11.4% NH2) with three different concentra-tions,1%, 3% and 6% in addition to control treatment for comparison. When larvae were fed on leaves of mulberry trees one day after Treatment, high mortality (up to 100%) was observed specially with 6% concentration. Mean weights of larvae, cocoons and cocoon shell and fecundity were negatively affected when compared to control. On the other hand, when larvae were fed on leaves of mulberry trees, no mortality occurred after two weeks of treatment in all concentrations, in addition, the mean weights of larvae at the end of 4th and 5th instar larvae, cocoons and cocoon shell s in-creased at 3% concentration compared with other concentrations and control. The highest fecundity occurred in female moths when lar-vae were fed on leaves of M .nigra compared with M. alba as well as 3% concentration com-pared with other concentrations and control.
اظهر المزيد [+] اقل [-]A Comparative Study Between Different Preservation Methods on The Viability of Some Yeast Cultures
2021
Reham Abdallah | Ibrahim Sayed Ahmed | amal hassan | hemmat Elshesheetawy
The influence of chilling, freezing, and dry-ing preservation methods on morphological properties and viability of four yeast cultures, isolated Saccharomyces boulardii (SB1 and SB2), Saccharomyces cerevisiae (SC), and Kluyveromyces lactis (KL), was studied. chilling preservation had no effect on yeast colony morphology parameters till the end of the preservation period in contrast with freez-ing and drying preservation methods. Drying preservation resulted in the highest viability decrement % of yeast cultures ranged between 59.38 to 40.21% as compared with other preservation methods. There is a noticeable re-duction in D values of preserved yeast cultures by drying, which varied from (33 to 26 day) in comparison to chilling and freezing preserva-tion that recorded (119 to 83 and 180 to 57 day), respectively. The obtained results re-vealed that chilling preservation under proper conditions, as well as freezing, is more prefer-able for the preservation of studied yeast cul-tures than that preserved yeast by the drying method.
اظهر المزيد [+] اقل [-]Potentiality of Using Mycorrhizae and Pseudomonas fluorescens in Reducing the Effect of Water Shortage on Broccoli Plants
2021
Dalia Abd El-Fattah | Fadl Hashem | Ahmed Farag
Accelerating global warming and water scarcity and improving water use efficiency are considered essential factors for achieving adequate crop development and productivity. Therefore, the authors targeted the use of arbuscular mycorrhizal fungi (AMF) and Pseudomonas fluorescens (Ps1) for improving growth, productivity, and water use efficiency of broccoli plants (Brassica olercea L. var. italica, cv. Belstar F1) under various irrigation regimes i.e., 50, 75, and 100% of crop evapotranspiration (ETc). Two greenhouse experiments were carried out in clayey soil. The combined inoculation of endomycorrhizae and Ps. fluorescens (Ps1) improved water use efficiency and consequently vegetative growth and yield. Under the applied irrigation regime 75% ETc of broccoli inoculated with both endomycorrhizae and Ps. fluorescens (Ps1) showed higher head weight (616 and 647 gram) than those grown under the irrigation regime 75% ETc combined with endomycorrhizae (568 and 559 gram) during the two seasons, respectively. However, a minimum yield value of 149 and 142 grams per plant was recorded for un-inoculated plants grown under 50% irrigation regime during both seasons. In conclusion, the combined inoculation with endomycorrhizae and Ps. fluorescens (Ps1) under irrigation regime 75% ETc was the optimum combination for increasing water stress resistance and broccoli productivity under water scar-city circumstances.
اظهر المزيد [+] اقل [-]Detoxifying Enzymatic Activity and Insecticide-Resistance Gene Expression in Field Populations of Pink Bollworm, (Pectinophora gossypiella (Saund.))
2021
Rabab Desouky Alam | Amgad Sobeiha | Abdel-Aziz Khdir | Naima Alsenosy
A study was conducted to assess two enzyme detoxifying activities and insecticide-resistance gene expression quantitation using real-time (PCR). Four populations of pink bollworms were compared with the baseline laboratory strain. Field populations showed higher levels of enzymatic activity, glutathione-S-transferase and β–esterases, than those of the laboratory strain. The amplification curves scored a cycle threshold (Ct) value of 25 for the ribosomal protein subunit7 (rps7). For the BtR gene, the Ct values of analyzed biological groups ranged from 20 for the laboratory strain to 24 for the Fayoum group. For Cad1, the Ct values ranged from 19 for laboratory strain to 23 for Fayoum and Qalubia populations. Therefore, the present work introduces a method for the challenge of monitoring resistance to Bt toxins in crops which requires, according to the IPM (Integrated Pest Management) program, a wise insecticide application.
اظهر المزيد [+] اقل [-]Susceptibility of Some Ornamental Plants to Aphid Infestation and Effects on Plant Biochemical Components and Morphological Structures
2021
Rania Rashwan
Aphid is a major insect pest attacking ornamental plants. It causes great damage by reducing the economic values of plants. The investigated research aims to determine the relation between leaf biochemical components, morphological structures of plant leaf surface and the susceptibility of seven ornamental plants to Aphid Infestation. Highest recorded aphid infestation was observed on Tecoma stans during 2017 and 2018 seasons followed by Rosa damascena and Jasminum grandiflorum. There was no rec-orded infestation on four inspected ornamental plants, Ruta graveolens, Schefflera actinophylla, Nerium oleander and Bougainvillea spectabilis. Activity of antioxidant enzymes plays as defense line when increasing the insect population density. Biochemical components are varied among different plants that prevents or reduces insect infestation, as tannins, total phenol, and Phenol oxidase. Trichomes are considered as main morphological character in plant defense system. These results enhanced utilization resistant ornamental plants due to preventing aphid infestation. It is considered one of the integrated pest management programs, that achieves health environment without more insecticidal application.
اظهر المزيد [+] اقل [-]Effect of seaweed extract and biofertilizer on organic production of common bean seeds (Phaseolus vulgaris L.)
2020
M Amin | M Elshinawy | M Abdallah | H Abd El-Gawad
At the Experimental Farm, Agriculture Faculty, University of Ain Shams, Qaliobia Governorate, Egypt, in order to investigate the influence of biofertilizer ( Bio. ); Rhizobium ( R ), mycorrhiza ( MF ), R + MF and control, seaweed extract (SWE) concentration (zero, one, two and four gram per liter) and their interactions on vegetative growth, productivity and quality of seed common bean cv. Nebraska. Before planting, the seeds were soaked in MF (glomus sp.) and sown on the first of March 2016 and 2017 seasons respectively. The experimental plot area was seven m2 (four rows). The length of each row was 2.5 m and width of 0.7 m. The plant's distance was seven cm on one side, and an alley (one width m) was left as a border between the treatments. After two weeks of planting, young plant were inoculated with R phaseolus after the first irrigation. Plants were sprayed three times of SWE (30, 45 and 60 days) after sowing. A split plot design with four replicates was used; where the main plots are Bio treatments and the subplots are SWE treatments. The obtained results clearly indicated that different applied treatments increased measured growth characteristics (No. leaves/ plant, leaf area and total chlorophyll (SPDS)), the yield and components of yield (No. pods/plant, seed yield /plant and seed yield) and chemical constituents (total protein, carbohydrates, nitrogen and phosphorus) in seed after harvest. As well as, the best results were obtained by interactions between SWE (two and four gram per liter) and Bio. (R + MF) treatments in the two assigned seasons So adding combination between Bio. ( R + MF ) and SWE (two or four g) to improve vegetative growth, productivity and quality of common bean seed could be recommended under organic system ( conversion to organic agriculture ).
اظهر المزيد [+] اقل [-]EXTERNAL DEMAND DETERMINANTS FOR EGYPTIAN FROZEN VEGETABLES
2020
Sahar Abdl Elrazek | A. Abdelmaqsoud | Eman Yossif | M. Salem
The frozen vegetable industry in Egypt is one of the most important industries that contribute to the provision of vegetables throughout the year to the consumer, and the Egyptian frozen vegetables value of exports of preserved food industries as the may reach $86.61 million on average for the period (2011-2015) with relative importance of 47.68%. The problem statement of research represent that the agricultural production in general and from vegetables and fruits in particular and the high percentage of lost and damaged, which threatens the development of Egyptian exports of these products if the export of Egyptian manufactured products does not keep pace with its international counterparts, Therefore, the research aimed to estimate the external demand for Egyptian frozen vegetables, and the determinants of that demand in the most important import markets of Egypt during the period (2007-2018). The research has reached some conclusions, including That Saudi Arabia, The United Arab Emirates, Jordan, the United States of America, Italy, and France are the most important countries importing Egyptian frozen vegetables, where the percentage of Egypt's exports of frozen vegetables to these countries amounted to about 57.1% of the total amount of Egyptian frozen vegetables exported during the period (2014-2018) Egypt's exports of frozen vegetables to these countries amounted to about 55.6% of the total value of Egyptian frozen vegetable exports for the same period. The high price elasticity of Egyptian frozen vegetables for the UAE market compared to the Saudi market with a value of about 1.5, 0.46 respectively, which means that the individual demand for frozen Egyptian vegetables for the Emirates is elastic, while the individual demand for frozen Egyptian vegetables for Saudi Arabia is inelastic. This reflects the importance of Egyptian frozen vegetables in the Saudi market and deal with them as a necessary commodity at a time when this importance is diminishing in the UAE market, where dealing with frozen Egyptian vegetables as a luxury goods. The same table also shows the increase cross elastisates of the Italian market by about 2.3 compared to the Saudi market, where the cross elasticity of those markets where 2.3, 1.3 respectively, which means that the degree of competition in the Italian market is higher than the rest of the markets. The italian market's income elasticity is also shown to be higher compared to the UAE and US market with a value of about 6.5, 2.2, 0.66 respectively. The methods of estimating the individual demand for Egyptian frozen vegetables using import statistics and using export statistics indicate different types of elastisates for the demand for Egyptian frozen vegetables for the Italian market and the Saudi and Emirati market from elastic demand to inelastic demand, which indicates the existence of Tri-Market Operation of Egyptian frozen vegetables are in these markets. The need to increase Egyptian efforts to revive the Egyptian frozen vegetable market in the UAE market as one of the most important export markets for these goods. Try to export directly to the countries which it is already exported by identifying the countries importing from Egypt to be an effective and real demand and not an indirect demand.
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