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Effect of Different Levels of Salinity and Anti-Transpiration on the Growth Characteristics and Chemical Composition of Panicum maximum (Jacq.)
2022
Adel El Wardany | Nasr Elbordiny | Ramadan Abdrabou | Adel Bakr | Yasser Abdelkareem
This study aimed to determine the effect of different salinity and anti-transpiration levels on the growth and biochemical composition of Panicum maximum plants (Guinea grass) during the spring and summer of 2020. Two different anti-transpiration treatments [molasses (sugarcane) (5 mL/L), kaolin (50 g/L) and control] and three salinity levels (S1 well water as the control and salinity S2 2000 ppm; S3 4000 ppm, S4 6000 ppm) were used in 12 treatments in 72 pots (3 anti-transpiration treatments × 4 salinity treatments × 6 replicates); a randomized complete design was used. Results revealed that the plants achieved the highest plant height (123.77 cm) and dry weight (521.87 g/m2) with kaolin and no salt addition treatment during summer. A higher percentage of proteins and carbohydrates were found in spring than in summer, but there was no significant difference in the salinity levels. A high percentage of ash and fiber contents was also observed during summer, with no significant differences between the anti-transpiration treatments. It could be concluded that P. maximum, as one of the most important fodder crops, could be cultivated in marginal lands, especially during the summer season.
Показать больше [+] Меньше [-]Impacts of Natural and Supplementary Foods on Some Biochemical Activities in the Bodies of Honeybee Workers
2022
Sobhia Sayed | Mohamed Elsherif | Adel Mahmoud Basuony | Naglaa Ghazala
The experiments were conducted during seasons (summer, au-tumn, winter, and spring) 2020–2021 to study the activities of invertase, adenosine triphosphatase (ATPase), and alkaline phosphatase (AlkP) as well as the determination of total proteins. These activities were determined in the bodies of adult honeybee worker, Apis mellifera, (house and forager bees) after feeding on three different diet groups (A) pollen cake, (B) supplementary diet and (C) control group during the four seasons. Group (A) received 50 g pollen cake + 250 ml honey syrup (2 honey: 1 water)/colony/three-day intervals, group (B) received 50 g Brewer’s yeast chickpea cake fortified with 4.2% pollen + 250 ml sugar syrup (2 sugar: 1 water) while group (C) received 250 ml sugar syrup (1 sugar: 1 water) only. Results indicated that the highest increase in total proteins was found in group B during the autumn season with house bees. Invertase activity was high in group A during the summer season with forager bees. The highest ATPase activity was observed in group B during the spring season with house bees, whereas the highest AlkP activities were found in group A during the autumn season with house bees.
Показать больше [+] Меньше [-]Improvement of Growth and Productivity of Mango Trees Using Some Growth Stimulants under Salinity Conditions
2022
Fatma Abdalla | Hassan Elwakeel | Noha Mansour | Sabry Osman
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.
Показать больше [+] Меньше [-]Utilization of Agro-Wastes for Bioethanol Production
2022
Sodaf Maan | Abdelwahab Abdelhafez | Asmaa Ahmed | Enas Hassan
Four agro-wastes were evaluated as substrates for bioethanol production. Seven of the pioneer isolates in the production of cellulase, xylanase and laccase enzymes were selected for soluble sugar and bioethanol production. The highest level of soluble sugar was produced on sugar beet pulp followed by corn cobs. The experimental design included using soybean okara and sesame husk as nitrogen sources added to the production medium. Extraordinary soluble sugar yields were obtained on sugar beet pulp or corn cobs in combination with soybean okara or sesame husk at the concentration of (0.3%) of either. Different concentrations of corn cobs or sugar beet (5, 10, 15, g/100 m medium) were mixed with optimal concentrations of nitrogen sources. Results showed that 10 g of sugar beet or corn cobs achieved the highest soluble sugar yield. The efficiency of four strains of S. cerevisiae for bioethanol production was investigated, S.cerevisiae (AUMC 14720) recorded the highest level of bioethanol on fermentable fungal broth after four days at 30°C.
Показать больше [+] Меньше [-]Phytoremediation of Pb and Cd by Alfalfa (Medicago sativa L.): An Applied Study in the Presence of Lettuce Plants (Lactuca sativa L.)
2022
Manar Morsy | Mona Nossier | Abd Ellatif Elsebaay | Shaimaa Abd-Elrahman
A pot study was conducted to investigate the potential of alfalfa for phytoremediation of soil artificially contaminated with different concentrations of Pb and Cd and their combinations. Harvested plants were divided and used for two purposes: (1) separation into roots and shoots, which were digested to determine N, P, K, Pb and Cd concentrations, and (2) the use of fresh shoots to prepare alfalfa extract representing each treatment. Subsequently, lettuce seedlings were grown in the same pots with the same soil and without adding fertilizers; the alfalfa shoot extract prepared from each treatment was added to the treatment itself. Lettuce crops harvested after 67 days from transplanting were divided into roots and shoots which were digested to determine the previously studied elements. In addition, soil samples were collected after harvesting alfalfa and lettuce plants and prepared for chemical analyses. Results showed that alfalfa is an effective accumulator plant for the phytoremediation of Pb- and Cd-contaminated soils. In addition, using the alfalfa shoot extract to fertilize lettuce crops was beneficial to their growth without any risk of translocation of heavy metals. Thus, we recommend adding alfalfa to crop rotations, especially where soils are contaminated with heavy metals.
Показать больше [+] Меньше [-]Effects of Foliar Amino Acid and Vitamin Applications on Heat Stress, Production, and Quality of Lettuce Head Improvements
2022
ٌRabie Gomaa | Usama Elbehairy | Mohamed Elshenawy | Alaa El-din Tantawy
This study was conducted to investigate the effect of amino acid and vitamin foliar applications on improving iceberg lettuce (Lactuca sativa L.) production and quality during the summer. First, two hybrids (Patagonia and Bruma) were grown hydroponically in June 2018 and 2019. Then, for five consecutive weeks, plants were sprayed once a week with Stress Free (a commercial product comprising 0.5% vitamins [vitamin B complex/ascorbic acid] and 0.5% selenomethionine) at concentrations of 1.0, 2.0, and 3.0 g/L and Aminomad (20% free amino acids) at concentrations of 2.0, 3.0, and 4.0 cm3 /L. Investigations revealed that all plant growth aspects were positively improved with all foliar spray treatments than with the control. Furthermore, while mineral contents (nitrogen, phosphorus, potassium, calcium, and magnesium) showed positive responses to the applied treatments, the highest dose of amino acids showed the highest marketable and total yield effects among all foliar spray treatments with the Patagonia hybrid. However, the marketable and total yield of lettuce heads was lowest with the control treatment without spraying.
Показать больше [+] Меньше [-]Deficit Irrigation Technique to Improve Water Productivity of Avocado Grown on Mulched Sandy Soi
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.
Показать больше [+] Меньше [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect
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.
Показать больше [+] Меньше [-]Isolation and Identification of Some Egyptian Ectomycorrhizal Sporocarps
2022
Aya Ahmed | Shawky Selim | Mona Zayed | Asmaa Ahmed | Dalia Abd El-Fattah
In contrast to the global countries, ectomycorrhizae members are not common in Egypt, however, they are very important in the afforestation of poor lands. Their occurrence in Pinus sp., Clerodendrum sp., and Eucalyptus sp. may help to explain why these trees are the most extensively dominant around the world, especially in Egypt. The identification and characterization of numerous ectomycorrhizal fungi often involve large morphological descriptions of sporocarps alone, which consequently, in some instances, raise arguments about the accuracy of these studies. The present work was achieved to isolate, identify, and characterize three ectomycorrhizal fungi from sporocarps combining morphological and molecular techniques. The morphological characteristics of tested species were assessed and compared to standard taxonomic literature. ITS-rDNA was utilized for molecular analysis using the universal fungal primers ITS1. Identification of these species was confirmed by comparing the sequences of amplified genomes of these species with respective species sequences in GenBank, followed by blast analysis.
Показать больше [+] Меньше [-]Evaluation of Some Indeterminate Exotic Genotypes of Tomato
2022
Wafaa Elsadek | Mohamed Elshinawy | Salah Eldin Elminiawy | Fahima Ayoub
The study aimed to evaluate the performance of 15 exotic indeterminate genotypes of tomato (Solanum lycopersicum L.) to determine their suitability for cultivation under greenhouse conditions. The study material was obtained from two globally known gene banks, namely, the Center for Genetic Resources of the Netherlands and the U.S. National Plant Germplasm System (GRIN-Global) of the United States Department of Agriculture. One locally registered hybrid, Asya, was used as the control. The experimental layout was a complete randomized block design with three replications. The data collected were vegetative, flowering, and fruit characteristics as well as the number of fruits and both early and total yield per plant. High significant differences were observed among the exotic genotypes and control for all the studied attributes. The mean control values of fruit weight, firmness and pericarp thickness were significantly high, and several of the exotic genotypes exceeded the control values for vegetative, flowering, and yield characteristics under study. The genotypes coded as G.21 (Allround), G.18 (Alicante), G.6 (Marsol), G.7 (Harzer Kind) and G.3 (Robar) are promising for their overall performance in the total yield per plant and can be recommended for further exploitation to produce hybrids.
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