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Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi
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.
Afficher plus [+] Moins [-]Phytochemical, Antioxidant and Antibacterial Activities of Golden berry (Physalis Peruviana L.) Extract and its Effects on the Storage Stability of Tomato Paste
2022
Anwar, Dina | Eed, Heba | El-Chaghaby, Ghadir A | Farid, Ahmed
This study focused on the phytochemical, antioxidant, and antimicrobial activities of the ethanol extracts of golden berry calyx and fruits. The phytochemical analysis of calyx and fruit extracts revealed high total phenols and flavonoids. High antioxidant capacity was recorded for fruit extracts. Fruit extracts also gave the highest antibacterial activity against Pseudomonas fluorescens, Escherichia coli, and Salmonella typhimurium. Furthermore, tomato paste was prepared using sodium benzoate and golden berry extract as food preservatives. The incorporation of golden berry extract and chemical preservatives maintained the paste quality indicators over the control samples. A rapid decline in total antioxidant capacity was also observed in control samples (21.6%) as compared with the treated samples (15.21% and 15.41% for sodium benzoate and golden berry extract, respectively) after 30 days of storage. This study demonstrated that dried fruit extract with high phytochemical and antimicrobial properties could be used as a natural food preservative.
Afficher plus [+] Moins [-]Evaluation of Orius laevigatus as a predator of Bemisia tabaci In Vitro
2022
Salama, Nada | Emam, Azza | washahy, Kadry | Gaffar, Saad
This study determined the ability of Orius laevigatus to consume different stages of Bemisia tabaci at various densities. Additionally, the use of B. tabaci as food and its effect on the life cycle parameters and female fecundity of Orius predator developmental stages were investigated. The results showed that O. laevigatus could consume whitefly at various stages and complete its preimaginal and postimaginal stages, with B. tabaci eggs, nymph instars, and adults as the only available food source. The consumption and fecundity of O. laevigatus were influenced by feeding on different stages of B. tabaci. Furthermore, the females of this predator consumed more eggs, fourth nymphal instar, and adults than the first, second, and third instar nymphs of B. tabaci on a different density level. The mean numbers of consumptions at different stages of B. tabaci increased with increasing prey densities. The result simply that O. laevigatus can be used as a predator in the biological control of tobacco whiteflies.
Afficher plus [+] Moins [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect
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.
Afficher plus [+] Moins [-]Steroidal Saponins as Antioxidant and Alleviator of CCl4-Induced Oxidative Damage in Albino Rats
2022
Eliwa, Hala | Ibrahim, Mervat | EL-Sayed, Salwa | Abdelhamid, Mohamed
Liver toxicity is a common condition that can be induced by environmental pollutants. The present study explored the hepatoprotective activity of steroidal saponins extracted from the yam plant versus CC14-induced hepatotoxicity in albino rats. Twenty-five albino rats were classified into 5 groups. Rats of group (G1) were provided a basal diet and drinking water and served as un-treated controls. Other groups were administered CC14 orally twice a week at a dose of 400 mg/kg. The second group (G2) did not receive any further treatment and served as positive controls while rats in the groups G3, G4 and G5 were administered saponins (50,100 and 200 mg/kg body weight, respectively) for six weeks in the remaining groups. The hepatoprotective activity of saponins was assessed by measurement of liver enzymes, kidney function tests, malondialdehyde content, and antioxidant defense enzymes activities in serum of these rats. Saponins administration improved liver and renal function and significantly increased the activities of catalase, glutathione peroxidase (GSH-PX), glutathione reductase GSH-RD and superoxide dismutase SOD. These increases were linked to a considerable decrease in serum malondialdehyde levels, indicating that lipid peroxidation was being mitigated. Thus, the concentration of saponins (200 mg/kg) is the best concentration of protection against CC14-induced hepatic injury, improved liver and renal function, and reduced oxidative stress in rats.
Afficher plus [+] Moins [-]Productivity Improvement of Canola Genotypes Under Salinity Stress Conditions by Integration between Mineral and Nano-Scale forms of Nitrogen Fertilizer
2022
Mohamed, Doaa | Fergany, Mohamed | Elhabbasha, Elsayed | El-temsah, Mohamed
Two field experiments were conducted during in 2019/20 and 2020/21 seasons to study the impact of integration among mineral and nanoparticle nitrogen (N) fertilizer levels on yield traits and chemical characters of some canola genotypes grown under salt stress conditions. Four treatments of N fertilization (190 kg N/ha as recommended dose; 50% of the recommended, 95 kg N/ha+nano nitrogen (5 L/ha); 25 % of the recommended, 47.5 kg N/ha+nano-nitrogen (5 L/ha), and nano-nitrogen (rate of 5 L/ha). canola genotypes (Trabber, Agamax, and Serw4) performance were assessed under three levels of saline irrigation water (control, 2000, and 4000 mg L-1). Results showed that increasing salinity levels up to 4000 mg L-1 led to decreasing in all studied yield parameters compared with those of control (tap water). Trabber genotype excelled significantly in most of the yield characteristics. Integration between nanoscale and mineral nitrogen fertilizer, i.e. 95 kg N/ha+5 nano N L/ha) showed superiority over all applied N treatments, recording the highest values. It could be concluded that since application of 95 kg N/ha+5 nano N L/ha exploiting the nano form of N saves about 50% of applied nitrogen in canola under saline conditions. Accordingly, nanoparticles help the environmental pollution to be reduced.
Afficher plus [+] Moins [-]DNA Barcoding for Some Medicinal Plants in the El-Omayed Biosphere Reserve
2022
Nabil, Reham | Rashed, Mohamed | Elmosallamy, Mahmoud | Elsherbeny, Esraa
DNA barcoding is a valuable tool for molecular identification of plant materials, which is primarily employed to guarantee the nature and therapeutic value of all available medicinal plants. Identification is crucial for the illegal medicinal plant trade, safe use, and preventing adulteration. In this study, DNA barcoding was used to evaluate and confirm the identification of some medicinal plants from the El-Omayed Biosphere Reserve (OBR). Two DNA regions, rbcL and ITS were selected due to their universality, ease of amplification and sequencing, and ability to identify taxa at the generic and species levels. The ITS region demonstrated a higher capacity for species discrimination power than the rbcL region. It assisted in identifying four of eight plants more precisely than rbcL. Together, ITS and rbcL could be used for plant species identification, conservation, and trade control of valuable plant resources.
Afficher plus [+] Moins [-]Inhibition of Rhizoctonia solani Growth and Its Extracellular Hydrolytic Enzymes by Different Extracts of Cinnamon (Cinnamomum cassia) and Black Cumin Seeds (Nigella sativa)
2022
Abd El Aziz, Seham | Abo-shady, Ahmed | Ibrahim, Mervat | Helmy, Maha
The present study evaluated the ability of different extracts of cinnamon and black cumin seeds to inhibit the growth of the phytopathogenic fungus Rhizoctonia solani and its extracellular cell wall degrading enzymes. Concentrations of 300 and 450 ppm of methylene chloride and hexane extracts of cinnamon completely inhibited the growth of R. solani after 72 hours of incubation at 25±1°C in vitro. Methylene chloride or hexane extracts of black cumin seeds at 4000 ppm after 72 hours inhibited the growth of R. solani by 37 and 39% respectively. Moreover, black cumin seed hexane extract at 2000 ppm inhibited 55% and 38% of the activity of pectin lyase (PL) and polygalacturonase (PG) respectively. In addition, the methanolic extract of black cumin seeds at 2000 ppm exhibited a significant reduction of exo-protease activity (74.8%). GC-MS analysis results showed that linoleic acid is the main component of the fixed oil fraction of black cumin seed hexane extract while (E) cinnamaldehyde is the main component in both hexane and methylene chloride extracts of cinnamon. HPLC-MS analysis of black cumin seeds methanolic extract showed that amentoflavone was the main component. Docking was used to identify the major component interaction with pectin lyase A and exo-protease.
Afficher plus [+] Moins [-]Improvement of Growth and Productivity of Mango Trees Using Some Growth Stimulants under Salinity Conditions
2022
Abdalla, Fatma | Elwakeel, Hassan | Mansour, Noha | Osman, Sabry
A study was carried out in a mango orchard on reclaimed land for two seasons in 2019 and 2020. The experiment was implemented on fifteen years old mango trees “Fagri Kalan” budded on seedling mango rootstock and planted at 4 × 4 m. This experiment involved two soil growth stimulants (K humate, magnetite) and foliar application with cobalt. The experiment involved two factors, the first one was soil application with K humate by two levels (50 and 100 g/tree/year) and magnetite by two levels (250 and 500 g/tree /year) plus control, whereas the second factor was a foliar application with Co as cobalt sulfate by three levels (0, 15, and 30 ppm Co). The experiment was carried out in a factorial experiment in split plot design with three replicates whereas each replicate was represented by two trees. Result indicated that soil application with K humate at 100 g/tree followed by magnetite at 250 g/tree or foliar application with Co at 15 ppm alone or the combination between (K humate at 100 g/tree and cobalt at 15 ppm) gave the highest values of yield/tree, fruit weight, TSS, reducing sugars, leaf N, P, K, and Fe content of “Fagri Kalan” mango trees grown under salinity conditions.
Afficher plus [+] Moins [-]Element Composition and Toxicity of Seaweed Algae (Ulva lactuca, Laurencia obtuse and Padina pavonica) Toward Shrimp
2022
Muhammad, Ahmed | Hassan, Ibrahim | Tawfeek, Manar | Ahmed Ibrahim, Hayam
This study examined the macro and trace element contents as well as the cytotoxicity of Laurencia obtusa, Ulva lactuca, and Padina pavonica algae collected from the Mediterranean coast of Egypt (Alexandria coast). The results indicated that the seaweed samples contained high concentrations of Ca, Cl, Mg, K, Na, P and Fe. The Cu and Zn contents of the algae were in the ranges of 0.39-0.95 mg/100 g dw and 0.11-0.49 mg/100 g dw respectively. Fresh red algae contained the highest level of Zn and Cu, whereas the iodine level was 1.52, 1.27 and 1.01 mg/100g in fresh each of Padina pavonica, Laurencia obtuse and Ulva lactuca respectively. Fresh red, fresh green, dry green, dry red, in addition to fresh and dried brown algae had maximum lead (Pb) levels of 0.16, 0.14, 0.13, 0.12, 0.04 and 0.02 g/100 g respectively. Fresh red algae contained the highest Cd and Mn levels, whereas dried brown algae exhibited the lowest Cd and Mn concentrations. Different extracts of fresh and dried brown algae exhibited significant larvicidal activity against brine shrimp. LC50 values indicated that dry samples were more cytotoxic than fresh samples.
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