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Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi 全文
2022
Mostafa Sokkar | Eslam Ahmed | Ahmed Ibrahim | Manal Mubarak | Mona Nosseir
Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi 全文
2022
Mostafa Sokkar | Eslam Ahmed | Ahmed Ibrahim | Manal Mubarak | Mona Nosseir
A field experiment was conducted in new reclaimed areas to improve avocado trees water productivity cultivated under deficit irrigation and mulching. The deficit irrigation treatments were 90, 80, 70, and 60% of reference evapotranspiration (ETo). Results revealed that The average water requirements during different avocado trees physiological growth stages were 613, 1509, 1755, 1391, and 632 m3 /fed for flowering to end of fruit set, fruit set to approximately 50% of the expected market fruit size, during the fruit growth stage, during the fruit ripening stage, and during the flower bud formation stage, respectively. These values represent approximately 10.4%, 25.6%, 29.7%, 23.6%, and 10.7% of the total yearly water requirement. The averages irrigation frequency were 2.45, 2.61, 2.72, 2.87, and 3.91day for 100, 90, 80, 70 and 60% ETo treatments, respectively. The highest crop water productivity value of 1.24 kg/m3 water was attained at 70% ETo followed by 1.18 kg/m3 water at 80% ETo while the least crop water productivity (1.06 kg/m3 water) was realized at 100% ETo. The crop water requirement of 5110 m3 /fed/year with high irrigation frequency is recommended for mulched sandy soil cultivated with avocado trees.
显示更多 [+] 显示较少 [-]Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi 全文
2022
Sokkar, Mostafa | Ahmed, Eslam | Ibrahim, Ahmed | Mubarak, Manal | Nosseir, Mona
A field experiment was conducted in new reclaimed areas to improve avocado trees water productivity cultivated under deficit irrigation and mulching. The deficit irrigation treatments were 90, 80, 70, and 60% of reference evapotranspiration (ETo). Results revealed that The average water requirements during different avocado trees physiological growth stages were 613, 1509, 1755, 1391, and 632 m3 /fed for flowering to end of fruit set, fruit set to approximately 50% of the expected market fruit size, during the fruit growth stage, during the fruit ripening stage, and during the flower bud formation stage, respectively. These values represent approximately 10.4%, 25.6%, 29.7%, 23.6%, and 10.7% of the total yearly water requirement. The averages irrigation frequency were 2.45, 2.61, 2.72, 2.87, and 3.91day for 100, 90, 80, 70 and 60% ETo treatments, respectively. The highest crop water productivity value of 1.24 kg/m3 water was attained at 70% ETo followed by 1.18 kg/m3 water at 80% ETo while the least crop water productivity (1.06 kg/m3 water) was realized at 100% ETo. The crop water requirement of 5110 m3 /fed/year with high irrigation frequency is recommended for mulched sandy soil cultivated with avocado trees.
显示更多 [+] 显示较少 [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect 全文
2022
Sobhy Mahmoud | Yasser Arafa | Ahmed Abo El-Hassan abdel aziz | Abdel-Ghany El-Gindy
AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect 全文
2022
Sobhy Mahmoud | Yasser Arafa | Ahmed Abo El-Hassan abdel aziz | Abdel-Ghany El-Gindy
Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.
显示更多 [+] 显示较少 [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect 全文
2022
Mahmoud, Sobhy | Arafa, Yasser | abdel aziz, Ahmed Abo El-Hassan | El-Gindy, Abdel-Ghany
Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.
显示更多 [+] 显示较少 [-]Design of Sprinkler Irrigation Systems Using an Expert System Program 全文
2021
Mohamed Alashram | Khaled elbagoury | Said Shaaban | Ahmed abdel-aziz
In this research, a rule-based expert system named EFSIS-ES (Engineering Factors of Sprinkler Irrigation System -Expert System) had been built, verified and validated. Therefore, the aims of this research were to build, verify and validate an expert system for making a decision for the normal user to maximize system efficiency of sprinkler irrigation. The inputs data included location data, climate data, pump data, crop data, soil data and sprinkler system data. The outputs of the expert system were number of the sprinklers on a lateral, number of laterals in the irrigation system, length of each lateral, main line length, irrigation frequency, required pump power, total dynamic head (TDH) and pump discharge output. Results showed high correlation (R2 = 0.9927) between the EFSIS-ES program and the designed spreadsheet in regard to irrigation frequency. It could be indicated high correlation (R2 = 0.9999) between the EFSIS-ES program and the designed spreadsheet regarding pump power. The regression coefficient (R2) was 0.9983 between EFSIS-ES program and SSSDPS Expert regarding total dynamic head (TDH). It could be indicated high correlation (R2 = 0.9979) between EFSIS-ES program and SSSDPS Expert regarding pump discharge output.
显示更多 [+] 显示较少 [-]Improvement of Irrigation Efficiency by Developing Surface Irrigation System 全文
2021
Marwa Mohamed | Mahmoud Hegazi | essam wasif | Osama Ahmed Bedir
The experiments were Carried out in Biahmu Village at Al-Fayoum Governorate, Egypt during the two winter seasons of 2018/2019 and 2019/2020, on wheat crop to (cv. Gemmiza 11) evaluate the traditional surface irrigation system "TSIS" and the improved surface irrigation system "ISIS"(terrace), under laser leveling with two slops (S1≈ zero% and S2 ≈ 3%). The evaluation parameters included; reduction in land loss "LL", the roughness coefficient of marwa-walls, water efficiencies (i.e., water conveyance efficiencies "WCE", water application efficiencies "WAE" and water storage efficiencies "WSE"), yield productivity "Yp", total applied water and water required, irrigation water productivity "IWP" and times of water advance, recession and opportunity. The results concluded that improving traditional marwa, led to reduction in land loss by 49.46% from the area of marwa, and "WCE" increased by 83.17% in improved Marwa "IM" the compare to Traditional Marwa "TM. It was observed that on the efficiency of water added to the field irrigated by "TM". The highest level of water productivity (1.79kg wheat/m3 water) was achieved in "IM" at a level of 3%. Advanced time "T.Adv" (min) decreased at 50, 50.77, 27.6, 20.75, and 17.17% and 30.9, 40.51, 22.8, 10.89 and7.05% for "TL and IL" by sloping to "S2".
显示更多 [+] 显示较少 [-]Reducing Fruit Sunburn and Splitting in Murrcot Tangarine Fruits by Using Silicate Application 全文
2021
Farid Mohsen | Mohamed Ibrahim
This experiment was done during 2019 and 2020 seasons on 10 years old Murcott tangerine trees (Citrus reticulata, Blanco) grafted on Volkamer lemon rootstock and grown under drip irrigation system at 3 × 5 m apart at a private citrus orchard at Sharkia Governorate, Egypt. The treatments were, Control treatment (sprayed with tape water only), Potassium silicate at 0.6 % (6 ml/ l), Aluminum silicate (Kaolin) at 4 %, Potassium silicate at 0.3 % (3 ml/ l) + Aluminum silicate (Kaolin) at 2 %. The treatments were done at 3 weeks intervals from mid-May to mid-August. The spraying was over the whole tree (canopy and fruits). Generally, all silica treatments improved yield, fruit quality and reduced sunburned and splitted fruits. The combined treatment of kaolin at 2 % + potassium silicate at 0.3 % (3 ml/ l), was the best treatment. Where, it reduced the sunburned and splitted fruits and improved yield, fruit weight, fruit dimensions, peel thickness, TSS% in comparison with other treatments. It could be recommended as a treatment for Murcotte tangarine trees
显示更多 [+] 显示较少 [-]Effect of Using Probiotics (ZADO®) on the Productive Performance of Nile Tilapia Fish (Oreochromis niloticus) 全文
2021
Shahinaz Abdelaty | Mohammed Osman | Hany Gado | Nagwa Maghraby | Zeinab Aly | Ali Elnadi
The research was performed at the Department of Animal Production's fish laboratory, National Research Center, Dokki, Egypt. The research was conducted to assess the impact of commercial powder probiotic (ZADO®) on growth efficiency of Nile tilapia mono-sex fish (O. niloticus), which were fed on basal experimental diet (the control group)and other 4 experimental diet, which was the basic diet augmented with 0.25,0.5,0.75 and 1% of ZADO® for T1, T2,T3,T4 andT5, respectively. The Five experimental treatments were performed in three replicates each, the experimental aquaria were part of closed recirculating system, where environmental parameters were kept constant throughout the experimental period. Fifteen aquaria 60 × 40 × 30 cm, width, depth, and height, respectively each was stocked with 15 fish. The mean individual initial body weight (4.04 g/fish) was recorded at the start of the experiment. All fish in each aquarium throughout the entire experimental period were weighed every two weeks. The experimental fish were fed 32 % crude proteinbased diet for (98 days). The daily feed allowances were calculated as 5% of fish body weight and were divided into 3 portions fed at 8 am, 12 pm and 4 pm. The Results of the experiment indicated that T2 had the largest significant (P<0.05) final body weight (FBW g/fish), average weight gain (AWG, g/fish), specific growth rate (SGR % day), feed conversion ratio (FCR), feed efficiency ratio (FER) and protein efficiency ratio (PER) among all the experimental groups. In addition, no substantial variations (p > 0.05) were found in protein productive value (PPV). Although significant effects (p <0.05) have been reported in fish body crud protein (CP) and fat (EE) in T2. By increasing ZADO levels in experimental diets higher than 0)25% no significant effect were observed.
显示更多 [+] 显示较少 [-]Early Removal of Mango Inflorescences Increase Tree Production and Fruit Quality (Mangifera indica L. cv. ‘Tommy Atkins’) 全文
2021
Ashraf Hamdy
The present investigation was carried out throughout the two successive seasons 2018 and 2019. Mango trees were grown in a private farm located at Wadi Elmullak El-Sharkia Governorate, Egypt. This study aimed to elucidate the impact of pinching early flowering in the winter severity on tree yield and fruit quality of Mango ‘Tommy Atkins’ cultivar. The old of the mango cultivar under this study was 15 years old and planted as 3x4 m apart grafted on ‘Saber’ seedling rootstocks, grown in sandy soil and irrigated through drip irrigation system. Mango trees were subjected to deinflorescence in mid-February by manual removing emerged inflorescence as follows complete removing (removing of 100% of emerging inflorescences), sever removing (75% of emerging inflorescences), moderated removing (50% of emerging inflorescences), light removing (25% of emerging inflorescences) and control (without removing inflorescences). Results showed that complete removing treatment significantly increased fruit yield as compared with other applications or untreated trees in the two studied seasons. Similar trend was observed regarding yield increment (%) where was superior to control treatment in the two seasons. Moderated and light treatments caused enhancement in some fruit physical properties when compared with 100% or 75% removal treatments. Complete removing treatment was superior to other treatments regarding total acidity percentage and vitamin C. In conclusion complete removing (100% of emerging inflorescences) in mid- Feb. could be a practicable choice for continued production for the ‘Tommy Atkins’ under the environmental conditions of exported mango orchards
显示更多 [+] 显示较少 [-]Isolation and Identification of Nonstarter Lactic Acid Bacteria from Traditional Baramily Cheese 全文
2021
Ahmed Ali | Youssef El-Kenany | Ihab Aumara | Osman Aita
Nonstarter lactic acid bacteria (NSLAB) have an important role in quality and safety of traditional Baramily cheese (Domiati cheese related type). Therefore, the objective of this study was to isolate and identify NSLAB with potential technological features from traditional Baramily cheese. Thirty-three samples of Baramily cheese randomly collected from retails in Cairo metropolitan area. The samples were characterized by physiochemical, textural profile and microbiological analysis. Ninety presumptive NSLAB (30 Lactobacillus spp < /em>. and 35 Enterococcus spp < /em>.) strains were isolated on MRS and Kenner-Faecal (KF) Streptococci media; and were characterized for growth temperature, salt tolerance and milk coagulation. All presumptive NSLAB isolates were tolerant to 6.5 % NaCl. Of them, 40 isolates were tolerant to 10.0 % NaCl including 16 presumptive Lactobacillus spp < /em>., and 24 presumptive Enterococcus spp < /em>. isolates based on the results, 11 representative isolates with potential technological features were selected for genetic identification using 16S rRNA technique, then were confirmed for growth and acidity development in skim milk within 48 h, and were tested for antimicrobial activity against some food spoilage and pathogenic microorganisms. The eleven isolates were identified as Ent. durans (1), Ent. faecalis (5), Lb. paraplantarum (1), Lb. plantarum (3), and Lb. rhamnosus (1). All isolated strains were confirmed active in skim milk, and some exhibited antimicrobial activity against tested food spoilage and pathogenic microorganisms. Both Lb. rhamnosus and Lb. plantarum were confirmed as the isolates with high activity in milk. Ent. durans and Ent. faecalis exhibited antimicrobial activity against Enterobacer aerogenes and E. coli. However, Lb. plantarum exhibited antimicrobial activity against both Enterobacer aerogenes, E. coli and Ps. aeruginosa. Listeria. monocytogenes, S. typhimurium, and Campylobacter. jejuni showed significant resistance to all tested NSLAB isolates. They can be concluded that the identified NSLAB isolated can be used to standardized and improve the quality and safety of Baramily cheese and other types related to Domiati cheese
显示更多 [+] 显示较少 [-]Changes in Food Expenditures in Urban and Rural Egypt 全文
2021
Mennat-Allah Hassan | Mohamed El-Eraky | Mohamed Kandeal
The aim of this research is to trace recent changes in family expenditures on food commodities between 2015 and 2017/18. The data is drawn from CAPMAS publications on family income, expenditure, and consumption for both years. Three food groups are explored in this paper: 1- The aggregate group of food and beverages; 2-The grains and bread group; and 3- The meat group. Two statistical models are utilized for the purposes of data analysis. The first model is known as Working's model and the second model is the well-Known double logarithmic model. The analysis shows that the expenditure elasticity of the aggregate group of food and beverages ranges between 0.423 for high-income urban families in 2017/18 to 0.763 for urban poor families in 2015. For rural families the same elasticity is about 0.313 for high-income families in 2017/18 and about 0.751 for poor families in 2015. These estimates are derived from the OLS estimates of Working's model. The double logarithmic model gives one single estimate for expenditure elasticity for the entire set of data. For example, the expenditure elasticity for all families in 2017/18 is 0.63 in urban areas and 0.59 in rural areas according to the double logarithmic model. The same estimates are 0.64 for urban areas and 0.56 for rural areas according to Working's model. The Working's model fits the family survey data quite well and gives multiple estimates of expenditure elasticity according to the level of family income. In contrast, the double logarithmic model gives one estimate of expenditure elasticity that does not change with the level of family income. That is Working's model would be more suitable for policy analysis purposes.
显示更多 [+] 显示较少 [-]A Standard Study to Estimate the Demand and Supply of Maize in Egypt 全文
2021
Mahmoud Hassan Abdallah | Mosaad Ragab | Mohamed AbdelFatah | El-Sayed El-Khishin
The agricultural sector is the main pillar of the Egyptian economic structure, as it represents main source of food and clothing. In addition, it contributes to of the national income and Egypt faces a deficit in agricultural production, on the other hand consumption exceeds local production, and food is considered a vital necessity for people that cannot be dispensed. This research includes the statistical assessment of the macroeconomic econometric model of the variables of demand and supply of maize during the period (2005-2019), and the problem has become one of the most important problems threatening development in Egypt It has dangerous dimensions for the agricultural sector in particular and for the Egyptian economy in general, and that Egypt is still suffering from a food gap in most food commodities in a way that threatens Egyptian food security, as the equation of imports of corn shows that the volume of imports decreases by about 0.31%, 0.70% each An increase in the import price in dollars per ton, the average per capita production of the current year by 1%, meaning that the most influential variable in the volume of imports of corn in a particular year was the import price in dollars per ton, the average per capita production. It was also found that about 65% of the changes in imports of corn are due to the change in the independent variables under study, and that the average imports, production, and consumption of maize during the same period is 10.39, 6.67, 17.60 million tons, respectively, 15 % increase in the import price causes decreased in the quantity imported by 0.31%, The average of imports, production, and consumption of maize during the same period was 10.66, 7.70 and 17.80 million tons, respectively.
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