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POPULATION STRUCTURE AND GENOME-WIDE ASSOCIATION ANALYSIS FOR SALINITY TOLERANCE IN BREAD WHEAT USING SNP, SSR AND SCOT MARKER ASSAYS Texto completo
2020
Alsamman Alsamman | S.D. Ibrahim | Mohamed Rashed | Ayman Atta | M.S. Ahmed | Alaa Hamwieh
Wheat is an essential staple food in the developing world, where demand is projected to grow exponentially in the future; simultaneously, climate changes are projected to reduce supply in the near future. One of the main consequences of climate change is salinity, which negatively impacts the world's cultivated area and therefore affects the global wheat production. Our objectives are to study the population structure of several Egyptian and international wheat accessions and to identify the genetic factors controlling the salinity stress response of bread wheat. In addition, we have attempt to identify genes that control some important agronomic parameters of wheat under salinity stress were identified. The wheat germplasm panel consisted of 70 accessions obtained from Egypt, Syria and Iran. The assessment of salinity tolerance was conducted over the years of 2018 and 2019 in the field and in the greenhouse. The genome association analysis (GWAS) and population structure analysis was conducted using six SCoT, five SSR and 93 SNP markers. Analysis of the population structure using allele frequency and phylogenetic analysis indicated that the studied wheat accessions were belong to four population groups. Where, for the most portion, Egyptian, Syrian and Iranian accessions are clustered depending on their country of origin. The GWAS analysis revealed 13 SNP markers that were significantly associated with morpho-agronomic wheat traits during salinity stress. These markers were closely related to genes that are known to have a direct link to wheat response to salinity stress such as CYP709B2, MDIS2, STAYGREEN, PIP5K9, and MSSP2 genes. This study revealed the genetic structure of adapted and imported wheat accessions, which could be used to select potential wheat accessions for local breeding programs. In addition, the SNP genotyping assay is a very potential technology that could be efficiently applied to detect genes that control bread wheat response to salinity stress.
Mostrar más [+] Menos [-]STUDIES ON COMPATIBILITY, FRUIT SET AND FRUIT QUALITY BY DIFFERENT POLLINATORS IN ANNA APPLE CULTIVAR Texto completo
2020
Mahmoud Maklad | Mai Anwar | نظمي عبد الغني | Nahla Awad
The apple (Malus domestica) is a member of the Rosaceae family. It is older than the rose in cultivation and is often referred to as the prince of the rose family. Pollen grains of Dorsett Golden, E25 and Ein Shemer were used to investigate their compatibility and incompatibility with Anna cultivar under the Egyptian climatic conditions during two successive experimental seasons of 2016 and 2017. The fluorescence microscope was used to determine the degree of pollen tube growth in style tissue after specific pollination treatments. Degree of self and cross compatibility and or incompatibility were determined, initial, and final fruit set percentage were calculated. Pollination treatments revealed that, pollens of the four apple cultivars exhibited high rate of the viability after 24 hr. in T.T.C test. Growth of pollen tube of the tested cultivars exhibited different pattern of compatibility, the pollen tubes of Dorsett Golden and Ein Shemer cultivars showed different levels of cross-compatibility when fertilized in Anna style tissue. The pollen tube of E25 cultivar grew slowly with heavy deposition of calluses along to the tube where its growth stopped in the lower part of Anna style four days after pollination. Therefore, they need pollinizer cultivars as for good fruit set. On the other hand, Anna self-pollination seemed to be self-incompatible and recorded lowest initial of fruit set percentage in the first and second seasons. The combinations of Anna × Dorsett Golden exhibited maximum percentage of initial and final fruit set in the two seasons followed by Ein Shemer pollens in both seasons. Insignificant differences were noted in fruit weight and fruit volume among all crosses. The highest acidity was found in hybrid Anna × Dorsett Golden in except in the first season TSS values of these crosses were not high and ranged between 11.83 % and 12.83 %.
Mostrar más [+] Menos [-]Assessment of Spectroscopic and Morphological Properties of some Fruit Crops under the Influence of Pollution with Heavy Metals Using Remote Sensing Techniques Texto completo
2020
Amany Abd Elhameed Elwesemy | Nazmy Abd Elghany | Ayman Abouhadid | Mohamed Aboelghar
Dietary exposure to a variety of heavy metals, including Ni, Cd, Cr, Pb, Zn, and Hg, has been identified as a danger to human health through fruits and vegetables, contamination of heavy metals is known as a grave risk to our climate. The study aims to develop empirical models to predict the concentration of heavy metals (Ni, Cd, Cr, Pb, Zn, and Hg) in the leaves of Citrus and Mango crops. The study was carried out in an observation site in Giza governorate that is cultivated by varied herbaceous and tree cover crops. This study area is suffering from severe pollution caused by near industrial district. The sample collected from deferent zones that are divided to six spatial zones and coded by from zone (2, 3, 4, 5, and 6). The distance between each Zone 10 Km that extends from the north to south and covers 60% from the Agriculture area in the Giza governorate. The main inputs of the generated models were spectroscopic remotely sensed data and laboratory analytical measurements of heavy metals in crop leaves. ASD (Analytical Spectral Devices) field spectro-radiometer was used to calculate hyper-spectral vegetation indices. Modeled heavy metal concentrations were tested against laboratory analysis through two common statistical tests; the Correlation of determination (R2) and Root Mean square (RMSE) error between predicted modeled heavy metals. Results shown the correlation coefficient of the generated models, red and near-infrared spectral bands demonstrated high precision and sufficiency for mango and citrus leaves to predict heavy metals. The models produced refer to specific regions with the same conditions. The overall results imply that hyper-spectral vegetation indices could be correlated with heavy metal content, while heavy metal content in plants may be influenced by many others. Remote sensing spectroscopy is a possible and promising technology to track the environmental pressures on agricultural vegetation. Additional ground remote sensing experiments are needed to assess the possibility of hyper-spectral reflectance spectroscopy in monitoring the stress of different types of metals on various plants.
Mostrar más [+] Menos [-]Effect of some edible coating and packaging on quality attributes of broccoli florets during cold storage. Texto completo
2020
Neama Hussein | Mamdouh Fawzy | Ahmed Abou El-Yazeid | Rawia Elbasiouny
Broccoli heads (Brassica oleracea var. Italica) Sakura F1 Hybrid were get from private farm in alnuwbaria Beheira Government. Heads were harvested at the appropriate stage of harvesting on 22th and 13th February 2017 and 2018, respectively, and then transported immediately to Horticulture Research Institute, ARC. The impact of edible coatings and packaging on the postharvest appearance and compositional quality changes of separated florets broccoli stored at 0°C were determined. Separated florets rinsed with chlorinated water (150 ppm) then washed by distilled water. The samples were then allowed to dry. Broccoli florets were dipped in chitosan solution at 0.5 and 1% concentration for 3 min. Carboxymethyl cellulose solution at 0.5 and 1% concentration for 3 min and distilled water represented as control. All treatments were dried and packed in non-perforated polypropylene bags (non-PPPb) or micro-perforated polypropylene bags (micro-PPPb) and stored at 0°C for 20 days plus 2 days at 10°C (shelf life). Results showed that loss of weight, decay, off odor, discoloration and peroxidase activity, of broccoli florets were increased as the storage period increased, while general appearance, total chlorophyll and total phenolic content were increased. For the influence of packaging material the results showed that there were significant differences between packaging materials on quality of florets. Broccoli florets which packed in non-perforated polypropylene bags (non-PPPb) had better florets quality as compared with those packed in micro-perforated polypropylene bags (micro-PPPb) during storage plus shelf life. Chitosan at 0.5 or 1% is the huge influence in reducing weight loss%, decay (score) peroxidase enzyme activity, off odor (score), discoloration (score) as well as in maintaining total chlorophyll and total phenolic contents during storage plus shelf life. Furthermore, florets dipped in chitosan 1% and then packed in non-PPPb was the most effective treatment in retarding loss of quality attributes, through the storage periods and helped in retarding deterioration and gave florets with good appearance after 20 days at 0°C plus 2 days at 10°C (shelf life) without decay.
Mostrar más [+] Menos [-]Genetic Improvement of Calendula officinal through Mutation Induction using Gamma Irradiation and Chemical Mutagens Texto completo
2020
eman elmenbawy | Eman Fahmy | Sawsan Elateek | Nahla Awad
Calendulais one of the basic plants of ornamentals. It is used in various purposes as cut flowers and in gardens. They are rich with active compounds such as chlorophyll a and b, phenols, flavonoid, and carotenoids. The present study focused on mutation induction in order to improve the morphology of the plant which can increase the turnout of its market. In order to examine which mutagen will make the most noticeable and permanent improvement of the plant. For the mutagens, seeds were treated with three doses of gamma ray (2500, 5000, 7000Gy) and two chemical mutagens; colchicine and EMS; which were applied at concentrations of 1000, 3000, and 10000 ppm. With the aim to measure the plant improvement, we measured the plant morphology, its active compounds and protein profiling before and after treatments with both γ-radiation and chemical mutagen to see which one has the most effective imprint on the plant. The morphological parameters data showed the highest plant high by the two doses; gamma dose of 7000 Gy and EMS concentration 10000 ppm, while the lowest dose of colchicine (1000 ppm) made the most impact on the plant height. As for the highest number of leaves/plant, it was obtained at 5000 Gy and 10000 ppm of EMS, while 1000 ppm of colchicine had the same effect. But the number of flowers/plant was not affected by the gamma radiation and colchicine but increased significantly by 10000 ppm of EMS. Surprise, the flower diameter was not affected by EMS while decreased at 2500 Gy and 3000 ppm of colchicine. Considering the importance of flower shape, all treatments either gamma radiation or chemical mutagens showed noticeable changes. Whereas, the biochemical parameters measuring the active compounds, both Chl-a, Chl-b and carotenoids contents increased at 5000 Gy, while flavonoid increased at 2500 Gy. Although, all doses of gamma ray eliminated the phenols content. While the lowest used concentration of colchicine (1000 ppm) increased both of Chl-a, Chl-b, flavonoid and carotenoids, even though the 10000 ppm of colchicine increased the phenol. On the other hand, the highest concentration of EMS (10000 ppm) increased Chl-a and Chl-b while carotenoids, flavonoid and phenol increased at 3000 ppm of EMS. The protein-profile analysis showed fluctuation in the gene expression. The highest performance appeared at 7000 Gy of gamma treatment,1000 -3000 ppm of colchicine, while the same result was obtained by EMS at 3000 ppm.
Mostrar más [+] Menos [-]تقییم السیاسات الزراعیة لآهم محاصیل الحبوب بإستخدام مصفوفة تحلیل السیاسات Texto completo
2020
Hala Mohamed Rashad | mahmoudom Odamy | Mosaad Ragab | Abdullah Abdel Maqsoud
- تبین من نتائج قیاس تحلیل مصفوفة السیاسات الزراعیة لمحصولی الدراسة أن معامل الحمایة الأسمی لمستلزمات الإنتاج قد بلغ حوإلی 0.915، 0.915 لکل من القمح والأرز خلال الفترة 2013- 2017، الأمر الذی یشیر إلی عدم وجود دعم لمستلزمات الإنتاج. - کما تبین أن معامل الحمایة الإسمی للنواتج من محصولی القمح والأرز علی الترتیب خلال فترة الدراسة قد بلغ حوإلی 0.771، 0.746، الأمر الذی یوضح إلی عدم وجود سیاسة إنتاجیة عادلة وذلک لقیام الدولة بفرض ضرائب مباشرة وغیر مباشرة علی المنتج وتقدیم دعم للمستهلک. - کما تبین من النتائج إلی وجود میزة نسبیة لمحاصیل الدراسة خلال نفس الفترة ، الأمر الذی یعنی إلی ان معامل المیزة النسبیة أقل من الواحد الصحیح. - کما تبین ان بمقارنة التقییم المإلی والتقییم الاقتصادی لکل من أجور الآلات، ثمن التقاوی، ثمن السماد الکیماوی، ثمن المبیدات، نجد أن التقییم المإلی یقل عن التقییم الاقتصادی لهذه البنود مما یدل على أنها مدعومة من جانب الدولة لمزارعی القمح. - کما تبین ان بمقارنة التقییم المإلی والاقتصادی لکل من إیجار الأرض، أجور الحیوانات، ثمن السماد البلدی، والمصاریف العمومیة یتبین أنهما متساویان مما یدل على عدم تدخل الدولة فی أسعار هذه البنود. - کما تبین ان بمقارنة التقییم المإلی والتقییم الاقتصادی لکل من أجور الآلات، ثمن التقاوی، ثمن السماد الکیماوی، ثمن المبیدات، نجد أن التقییم المإلی یقل عن التقییم الاقتصادی لهذه البنود مما یدل على أنها مدعومة من جانب الدولة لمزارعی الأرز. - کما تبین ان بمقارنة التقییم المإلی والاقتصادی لکل من إیجار الأرض، أجور الحیوانات، ثمن السماد البلدی، والمصاریف العمومیة یتبین أنهما متساویان مما یدل على عدم تدخل الدولة فی أسعار هذه البنود. - کما تبین من النتائج إلی أن قیمة معامل الحمایة الفعال لمحصول القمح بلغت حوإلی 0.756 خلال فترة الدراسة، مما یعنی أن محصول القمح لم یتمتع بحمایة حکومیة خلال تلک الفترة. - کما تبین من النتائج أن قیمة معامل الحمایة الفعال لمحصول الارز بلغت حوإلی 0.723 خلال فترة الدراسة، مما یعنی أن محصول الأرز لم یتمتع بحمایة حکومیة خلال تلک الفترة.
Mostrar más [+] Menos [-]Assessment and Spatial Analysis of Sensitivity to Desertification in Wadi El Natrun, Northwestern Egypt using MEDLAUS model Texto completo
2020
Hoda Nour-Eldin | Abdel -Aziz Sheta | Adel Shalaby | Mohammed Abd- El Wahed | Mohamed EL-Shinawy
Land degradation is a global environmental issue, given the various negative impact on socio-economic and ecological implications. It leads to reduced production capacity in addition to soil erosion, physical /chemical /biological /economic land deterioration, and long-term loss (or degradation) of vegetation. When a severe deterioration in drought areas called the process of desertification i.e. arid, dry sub-humid and semi-arid areas. Desertification processes reduces the productivity of the soil and as a result effect on food stocks. The main objective of this study is integrating remote sensing data and a geographic information system (GIS) to evaluate the environmental sensitivity for desertification in Wadi El Natrun, Egypt based on the Mediterranean Desertification and Land Use (MEDALUS) approach. The collected soil data; from description of represented soil profiles and analysis of soil samples, in addition to climate, plant cover, and management data were considered for assessing the sensitivity of desertification. The obtained results showed that 10.4 % of Wadi El Natrun area is considered severe sensitivity to desertification as a result of alkalinity and salinity, while the moderately sensitive area occupies approximately 10.93 % of the study area. The low sensitive one exhibits 76.3 %. This area is described by high soil quality because of the study area is one of the new development areas which were not affected by the factors of desertification. It can be concluded that the desert extension of El-Beheira Governorate (i.e. Wadi El Rayan) is one of the areas that possess valuable land resources which should be considered for future land reclamation projects. Similar international studies are recommended to be achieved with the use of multi-criteria GIS modeling (i.e. MEDALUS) which considered all relevant factors in the form of thematic layers for easier implementation and assessments. Present study represents one of the initial attempts to use the MEDALUS model for desertification assessment in the desert extension of El-Beheira Governorate.
Mostrar más [+] Menos [-]Effect of seaweed extract and biofertilizer on organic production of common bean seeds (Phaseolus vulgaris L.) Texto completo
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 ).
Mostrar más [+] Menos [-]EFFECT OF CERTAIN PSEUDOMONAS FLUORESCENS ISOLATES ON THE INFECTION OF ROOT-KNOT NEMATODE, MELOIDOGYNE INCOGNITA IN TOMATO AND EGGPLANT AND THE PLANT GROWTH Texto completo
2020
Nora Saleh | A Mahgoob | Entsar Taha | Wafaa El-Nagdi | M Youssef | Mona Zayed
Under screen house conditions, two experiments were carried out to evaluate certain bacterium, Pseudomonas fluorescens isolates regarding reproductive potential of root-knot nematode, Meloidogyne incognita, infecting tomato or eggplant. Results on tomato revealed that, on the basis of average total percentages nematode reduction, the over topped results were gained with P. fluorescens (Pf2) which recorded the highest significant (P≤0.05) average nematode reduction (61.3%) and higher percentage reduction of females (77%) per plant. The second rank was obtained by Pf3 which reduced all nematode numbers as an average of 56.9%.On the basis of average total percentages plant growth and weight of fruit increases, four bacterial treatments can be ranked in a descending order as follows: Pf9 > Pf4>Pf1and Pf7, as they achieved the highest average total percentages increases of 96.0, 47.3, 38.2and 29.8%, respectively compared to other treatments and untreated check. Regarding to eggplant, the over topped results observed was achieved by P. fluorescens (Pf10) which recorded the highest average total nematode reduction (66.2%) with higher reduction of (J2s) in roots (89.9%) per plant and in soil (78.8%) per pot. The second rank was obtained by Pf9 and Pf2 where they reduced all nematode numbers as averages of 55.9% and 54.9%, respectively. Also Pseudomonas isolates enhanced the plant growth of eggplant, averages were found in a descending order as follows: Pf1 (20.0%), Pf9 (18.7%) and Pf10 (18.3%) . It is worthy to note that the most distinct growth criteria was fresh weight of roots as it achieved higher percentage increase (58.1%) by using Pf9 followed by Pf1 as it caused 40.6% increase compared to untreated check. The highest average percentage of fresh weight of shoot were recorded for Pf10 (26.4%) and Pf8 (22.1%). Whereas for dry weight Pf3 (29.8%) and Pf2 (19.1%). In conclusion, the tested biocontrol agent was efficient in controlling the root-knot nematode on tested plants.
Mostrar más [+] Menos [-]Assessment of coffee-based agroforestry system performance by provinces in the Central Highlands of Vietnam Texto completo
2020
p Hoi | N Manh | T Vien
Dominated by intensive coffee monocultures for the last 30 years, farmers in the Central Highlands of Vietnam has been increasingly experienced with farming difficulties given resource degradation, market and climate uncertainties. In recent years, a number of farmers have diversified their coffee farms toward the forms of agroforestry: through integrating fruit and other crops into coffee farms. This study, by referring to the existing 10 agroforestry systems and 10 forestry ecological zones identified in the region for its approach, conducted in 20 communes throughout five provinces in the region at the coffee harvesting period in the end of 2018. In total, 249 farmers were identified through snowball sampling technique and successfully interviewed. Five major agroforestry systems are identified with sufficient sample size for statistical analyses. By detailed assessment of inputs used and revenue, this study proves that agroforestry systems strongly enhance farmer’s income. However, the success varies among the five studied provinces. Farmer’s technical know-how and their choice on 2nd crop made their agroforestry farming profit largely different. Given the fact that large percentage of land in the tropics is too dry, too steep, or too rocky to be classified as arable land which has been further problematic through increasing exposure to erosion resulting from unsustainable farming practices, often driven by intensive monocultures, efforts to promote agroforestry in Vietnam in particular and the tropics in general is thus needed, not only for surviving increasing population but also recovering and protecting the environment. In the situation of the Central Highlands of Vietnam, together with efforts in promoting agroforestry, a restructure of farming system needs to be considered in accordance with foreseeable difficulties in farming conditions, i.e., more water stress will be happened in certain provinces. These provinces should take a shift more toward less-irrigation dependent crops and reduce their dependence on coffee. These changes will create a better common guarantee for all farmers in coping with future uncertainties.
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