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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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]Impact of Bio- and Chemical Fertilization on Growth, Yield, Essential Oil and Chemical Composition of Fennel (Foeniculum vulgare Mill.) Plant
2021
Omniea Allam | Soheir Hassan | Awad Kandil | Ahmed Abdel Hamid | Abdallah Korayem
A pot experiment was carried out in seventeen levels of fertilization to evaluate the effect of the bio-fertilizer mixture alone or in combination with chemical fertilizer (NPK) on Fennel (Foeniculum vulgare Mill). Bio-fertilizer was a mixture of Azotobacter chroococcum, Bacillus circulans and Vesicular-arbuscular mycorrhiza. Results indicated that the use of bio-fertilizer at 3.75 ml/pot four times with 25% of NPK gave the highest significant values of vegetative growth, yield parameters, and NPK uptake; how-ever, fertilizing with bio-fertilizers without NPK application showed the lowest significant values in the two experimental seasons. The same addition of bio-fertilizer gave the highest significant values of total microbial count of soil and increased cumulative CO2; whereas the addition of 100% NPK gave the lowest significant values in both seasons. The full dose of NPK significantly increased volatile oil percentage while the addition of bio-fertilizer only significantly decreased it in both seasons. GC analysis of essential oil showed that the highest percentage of anethol (12.77 %) was obtained by applying 3.75 ml/pot bio-fertilizer added one time + 25% NPK and de-creased estragole (72.78%).
Afficher plus [+] Moins [-]Effect of New Solar-Drying Designs for Chamomile Essential Oil Yield and Its Chemical Constituents in Egypt
2021
Mohamed Abutaleb | Tamer Ragab | Yosry Abdeldaim | Alaa Mohamed
Egyptian medicinal and aromatic plants (MAPs) sector suffers from poor drying conditions of the product in terms of quality and safety standards, lack of professional advisory services, in addition to a high undeveloped value chain. Four designs were established in this study and focused on different methods for chamomile drying, the results of the 8/9/2 (B) design of the solar-assisted stack dryer were a masterpiece and promising for drying chamomile plant. The results of volatile oil extraction showed that an increased yield of volatile oil extraction by 30 % compared with traditional drying methods (control). GC-MS analysis indicated the essential oil chemical composition for the new drying method, were found to be the main active compound Bisabolol oxide A which were 54% in 8/9/2 (B) design of the solar- assisted stack dryer compared with the control which was 38.36% in control. The study method was promising and distinctive because it increases the yield of volatile oil extraction, maintains chemical structure compared with the control.
Afficher plus [+] Moins [-]Phylogeny Validation for Some Egyptian Brassicaceae Endemic Species
2021
Shaimaa Abd Elhady | Abdoallah Sharaf | Aly Salam | Khaled Abd El- Atey | Asmaa Abu Shady
A crucial menace for the biodiversity in arid and semi-arid territories is the global warming arising from anthropogenic activity. Egypt is expected to undergo an acute rainfall decrease and temperature boost in the next few decades, leading to many plant species' geographical allocation. Endemic plants of pleiotropic economic importance are strongly affected by climate change prospects, which will gradually result in losing our plant wealth genetic resources. Due to few studies on the Egyptian Brassicaceae family which has an economically and medicinally importance due to the presence of many active compounds that are included, in the pharmaceutical and cosmetic components (e.g., glucosinolates) besides having a large amount of antioxidant which inhibit the growth of microbes and also treat rheumatic diseases. The identification of this family still kind of fishy as researchers mostly relies on the morphological characters. To globally sustain this Egyptian plant family wealth's genetic pattern, it is substantial to characterize them based on their authenticated genetic background. Here we present a phylogenetic analysis of 16 species of the Egyptian Brassicaceae family using two plastid coding genes; Ribulose-1,5- bisphosphate carboxylase oxygenase (rbcL-a) and maturase K (matK). The maximum likelihood of the two markers for our samples was concordant with the Brassicaceae's references-sequences, which exist on plastid are considered highly conserved biomarkers. In conclusion, we have generated a robust phylogeny tree based on the molecular level that validates the Egyptian plant species and reliably differentiates them on morphological identification. This study is considered the first phase of Egyptian Brassicaceae family species authentication followed by biochemical studies serving the pharmacological and medicinal fields
Afficher plus [+] Moins [-]Rural Women's Practices in the Field of Food Preservation and Storage in Beheira Governorate
2021
Rehab Hanafy | heba mohamed | Zeinab Abdelrahman
The research aimed to Identify the practices of rural women in preserving and storing food in a village in Beheira Governorate, Identify the level of application of the respondents to good practices in preserving and storing food, Identify the most important sources from which the respondents obtain their nutritional information on food preservation and storage, and Identify the most important factors affecting the application of Respondents practice related to food preservation and storage. The research was based on the social survey method in the sample by selecting a random sample of (164) respondents at a rate of 7% of the total (2333) Families in Al-Naqidi village in Kom Hamada district in Beheira Governorate, data were collected through a personal interview using a questionnaire form during May and June 2020, frequencies, percentages, Pearson's simple correlation coefficient and Step-Wise multiple regression analysis method were used to analyze the research data. The results indicated that about (48.8%) of the total respondents had a high level of negative practices, (43.9%) of the total respondents, their level of application is medium, while about (7.3%) of the total respondents their application of these negative practices is low the majority of respondents depend on traditional sources (television, mother and relatives and neighbors) to obtain their nutritional information for food preservation and storage. The results indicated that the most important variables responsible for the application of the research for preserving and storing food, which affected by (38.7%), are: the age of the respondent, membership of social organizations, exposure to cooking programs through various media, and contact with the agricultural guide.
Afficher plus [+] Moins [-]Evaluation of Salinity Tolerance on New Selected Almond × Peach Hybrid Rootstocks
2021
ghada soliman | shimaa farhan
The main objective of this investigation was to evaluate the determination effect of salt tolerance of five new almond× peach hybrid rootstocks namely hybrid 1, 2, 3, 4 and 5 through their vegetative growth parameters and chemical concentrations. This evaluation aimed to recommend these rootstocks for the commercial use. This experiment was carried out at the Horticulture Research Institute, Agriculture Research Center, Giza, Egypt, during two successive seasons (2018-2019 and 2019- 2020) respectively. Rootstocks chosen for this study included new almond× peach rootstocks which are resistant to nematode. Salinity irrigated water included four levels of NaCl salt which was 500, 1000, 1500, 2000 ppm and the control which was the usual irrigated water. Results cleared that increasing salinity levels led to reduction in all growth parameters including seedling stem diameter, heights, average leaves number and buds per one, leaf area, fresh and dry weights. High salinity levels declined gradually mineral concentrations like N, P, K, Mg%, Fe and Mn ppm. Moreover the highest level of salinity conducted to the highest level of Na and Cl ppm concentrations. Chlorophyll values take the same trend while proline values take the opposite trend with high salinity due to it considered an indicator to high salinity. Moreover, there were differences between rootstocks to salinity tolerance. Hybrid No.5 was the most resistant hybrid to high salinity concentration followed by hybrid No.4 while hybrid No.3 was the least one. Hybrid No.5 reached the highest values of growth parameters and it shared with hybrid No.4 the highest values of N, P and K, Mg concentrations and the highest levels of Fe, Mn, Na and Cl. Chlorophyll values take the same trend with slightly differences with hybrid No.4. On the other hand hybrid No.3 was the least hybrid in all growth measurements, mineral concentration and chlorophyll except proline concentration it recorded the highest value. From the above investigation we can recommend hybrid number5 or hybrid number4 which had the best results compared to other seedlings rootstock under experiment salinity conditions.
Afficher plus [+] Moins [-]Economic Efficiency Analysis of Mango Farms Inputs in Ismailia Governorate
2021
Mohamed Esmail Nofal | Bahaa El-Din Morsy | hussein sarhan
Mango is considered one of the most important fruit crops in Egypt due to its widespread cultivation compared to other fruit crops and in addition to its importance as an important fruit crop it comes in third place after both citrus, oranges, grapes in terms of its contribution to the monetary value of the total Egyptian agricultural exports, and can be crystallized the problem of studying in the possibility of answering questions about what is the concept of the optimal economic size of the farm? What are the factors affecting farm sizes? What are the different measures of farm sizes? What is the optimal economic size of mango farms in new and old lands? To what extent is there a moral impact on the productive efficiency of the farm in question? The research aims generally to measure the optimal size of mango farms in new and old lands and estimate the production functions to identify the value of the marginal output of the various factors of production and estimated the total productivity flexibility of the function by about 1.07 this indicates that the increase of these production elements by the estimated function of 10% leads to an increase in the total output of the acre of mango by about 10.7 % which means an increase in the yield of capacity. The marginal output and average output per productive component were derived from the total output function of the study sample as table (1) showed that the (M.P) for both human labor and nitrogen fertilizer was estimated at about 0.018, 0.029 tons for those productive elements on The order as estimated the value of the marginal product of these productive elements about 210.42, 339.01 pounds respectively.
Afficher plus [+] Moins [-]Improvement of Fungal Phytase Production and Its In vitro Application in Ruminant Nutrition
2021
NOHA HASSAAN | Abd El-Nasser khattab | M. Khorshed | N. El-Bordeny | A. Abedo | M. Shoukry
Various fungal genotypes (Aspergillus niger NRRL 3135 (AN1), Aspergillus niger NRRL 326 (AN26), Aspergillus terrus F2-Kh (AT) and Mucor racemosus NRRL 3639 (MI)) were studied for their ability to produce phytase and improve the produced enzyme by ethyl-methane sulfonate (EMS) mutagenesis. AN1 showed the highest phytase activity on phytase screening medium supplemented with glucose (PSMG) after 8 days of incubation (reached 1875.40 IU/mL). The phytase activity of AN1 increased with increasing incubation time and the highest value was achieved at 12 days of incubation (2859.33 IU/mL). The exposure of AN1 spore suspension to 200 mM of EMS for different times enhanced the phytase activity and that mutant 20 Mn exhibited the highest phytase activity (reached 4520.5 IU/mL) therefore it was chosen for the next experiment. An in-vitro gas production procedure was carried out to evaluate the impact of using various amounts of laboratory produced phytase (PE) compared with commercial phytase (Axtra® PHY) on nutrients availability of ruminant's ration. Six levels (0, 400, 800, 1200, 1600 and 2000 IU phytase-1Kg dry matter) of phytase enzyme were evaluated with tested ration consisted of 40% berseem hay (BH) and 60% concentrate feed mixture (CFM). In-vitro dry and organic matter degradability (IVDMD and IVOMD), total gas production (GP), short chain fatty acids (SCFA’s) and inorganic phosphorus (Pi) concentration were improved significantly (P<0.05) by phytase addition from the two sources of phytase and the highest significant (P<0.05) values achieved at the level of 1200 IU. Results suggest that phytase activity was influenced by exposure to EMS mutagen compared to the wild type. Also, the produced enzyme source has the ability to improve the utilization efficiency of phytate diets as evidenced by the significant (P<0.05) increase in all tested parameters compared to the commercial source.
Afficher plus [+] Moins [-]Combining Ability for Grain Yield and Some Agronomic Traits in Diallel Crosses of Bread Wheat under Nitrogen Stressed Conditions
2021
yassmin mohamed
Six bread wheat genotypes and their 15 F1 crosses were evaluated under two nitrogen fertilization levels (40 and 80 kg N/fed) to estimate combining ability for days to heading, plant height, spike length, number of spikes/plant, kernels number/spike, weight of 100-kernels and grain yield/plant during 2018/19 season. Results revealed that significant nitrogen levels (N) mean squares were detected for all studied characters. Mean squares due to genotypes (G), parents and crosses for the studied characters were significant at both nitrogen levels and their combined analyses. Also, G x N interaction was highly significant for the studied characters. The general and specific combining ability variances were found to be significant for all studied characters at both-N-levels and their combined analyses. GCA/SCA ratios were less than unity for all studied characters at both N-levels and their combined data. The behavior of gene action varied from nitrogen level to another where the interactions of GCA and SCA with nitrogen levels were significant for most studied characters. Sakha 93 was identified as the most useful source for increasing favorable alleles for grain yield/plant, kernels number/spike and weight of 100-kernels under N-stress conditions, while Giza 168 was the best combiner for earliness at the two N levels. Cross combinations; Sakha 93 x Sids 12 and Sakha 93 x Misr 1 gave the best SCA effects for grain yield/plant under N-stress conditions. Significant positive correlations were detected between means of parents and F1 crosses with their GCA and SCA effects for most studied characters under the two nitrogen levels, respectively
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