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Molecular Identification of Some Rhizobium and Serratia Isolates as Potential Producers of Indole-3-Acetic Acid
2023
Shaimaa Sello | Ashraf Abdel Razik | Samir Ibrahim | Sawsan Elateek
In order to reduce the use of chemical fertilizers, the use of biological inoculants has been increased. Beneficial microorganisms are used to increase crop yields by stimulating plant growth through the production of phytohormones. In the present study, Indole Acetic Acid (IAA) production was analyzed in 18 bacterial isolates with Plant Growth-Promoting (PGP) capabilities; 15 of these isolates were Rhizobium, and three were Serratia. All isolates have been characterized morphologically and biochemically, and their IAA production in the presence of tryptophan, a precursor for IAA biosynthesis, has been evaluated. IAA production was detected using the Salkowski reagent with CT-2200 spectrophotometer at 530 nm. The levels of IAA production varied between the different isolates. The top two IAA producers were selected for genetic identification using 16SrRNA primers (27F and 1492R). One of the Rhizobium isolates (NRC-R2) shared 95% sequence similarity with Rhizobium sp., according to a Blastn search in GenBank and Rhizobium leguminosarum, whereas the Serratia isolate (Ain Shams Center for Genetic Engineering and Biotechnology (ACGEB)-S2 was 99.5% similar to Serratia sp. Accordingly, these two isolates could serve as biological sources for IAA.
Mostrar más [+] Menos [-]Predicting and Optimizing Tillage Draft Using Artificial Network Technique
2023
Yasmin Shehta | Nabil Awady | Abdel-Fadil Kabany | Mohammed Abd-Elwahed | Waleed Elhelew
Tillage as one of the agricultural practices consumes the largest amount of energy, which reflects on the total production cost. The artificial neural network (ANN) technique was utilized in the current study to opti-mize the performance of the tillage process. The ANN-modeled multilayer perceptron network with a backpropagation learning algorithm and momen-tum term was used by the PYTHON program. The ANN inputs were: the implement type, soil texture, moisture, bulk density, width, speed, and depth. The draught was the output (kN). Five layers composed the ANN model's optimal configuration (13-64-16-4-1). The linear and rectified linear units (ReLU) functions were utilized with hidden layers and the output layer, re-spectively. Momentum term and learning rate were 0.00003 and 0.9 respec-tively. The iteration number was 1000 epochs and stopped at 290 epochs. The coefficient of determination in the test datasets was high (0.92) while the difference between actual and predicted output was low (2.08). Bulk den-sity and depth were the main determinants of the draft. The evaluation of the developed model for chisel, moldboard, and disk plow gave satisfactory re-sults of 0.985, 0.924, and 0.917. In comparison to the ANNs, the regression model's correlation coefficient for predicting draught force was the lowest (0.373).
Mostrar más [+] Menos [-]Description of Leafhopper, Hebata (Alboneurasca) decipiens (Paoli, 1930) and Its Transmitting Phytoplasma Infesting Sugar Beet Plants
2023
Heba Ibrahim | Azza Abdelrahman Emam | Ahmed Bondok | Magdy Ahmed | Amro Abd-Elraheem
Sugar beet (Beta vulgaris L.) is the second sugar crop for sugar production after sugar cane worldwide. This plant is subjected to the infestation of several insect pests that cause considerable damage, especially leafhoppers, that can transmit phytopathogens (e.g., phytoplasma). In this work, we identified and described the leafhopper, Hebata (Alboneurasca) decipiens, in addition to the detection and molecular identification of Candidatus Phytoplasma that was transmitted by this leafhopper on sugar beet plants from naturally infected sugar beet plants to an uninfected one. The 16S rDNA gene from phytoplasma was amplified by a nested polymerase chain reaction (PCR) assay and directly sequenced using specific primer pairs DNA fragments. The resulting sequences were analyzed and compared with another phytoplasma sequence available at GenBank sequences performing BLAST using DNAMAN.
Mostrar más [+] Menos [-]Partial Gap-Filling of the Nile Tilapia (Oreochromis niloticus) Draft Genome
2023
Hala Zoghly | Mohamed Rashed | Mahmoud Magdy
Nile tilapia is a freshwater fish of African origin, with productive and economic characteristics affecting global fish markets. The Oreochromis niloticus reference genome has a diploid set of 22 linkage groups (LGs) in addition to ungrouped sequences. A total of 42,622 genes have been identified, but 550 genomic gaps may include more. Our study focused on some of these genomic gaps, where appropriate primers were designed and then multiplied through the polymerase chain reaction (PCR) technique. From local samples, DNA was extracted and amplified with the new primers. Successful amplicons were sequenced and annotated using available bioinformatics tools. Five assessed sequences were annotated, of which three were newly predicted in O. niloticus, as mucin 1-like, and KLR genes, and SATB region. The other two sequences belonged to grid2 and trpm7 which were previously predicted. Although individual attempts to identify genomic gaps are not feasible in filling the large lack of information on the Nile tilapia genome, a good number and valuable new information has been reached. However, the following plan showed many technical problems, more time, effort and cost that could be avoided by suggesting the application of another technique, such as whole-genome sequencing, mapping, and assembly.
Mostrar más [+] Menos [-]Effect of Rumen-Protected Choline Supplementation on Growth Performance of Fattening Calves
2023
Abdelrahman Amin | Ahmed Marwan | Fouad Abdelaziz | Nasr Elbordiny
This study aimed to evaluate the influence of choline chloride supplementation on the growth performance of feedlot calves. Thirty-two crossbred calves with a mean initial body weight of 305.71±4.09 Kg were divided into three groups of 10, 11 and 11 animals, randomly. The animals were distributed to one of three dietary treatments, control, choline15 and choline 30 (the rations supplemented with 0, 15 and 30 g choline chloride, respectively). The animals were fed on concentrate feed at a rate of about 2.15% of their live body weight and rice straw open access. Supplementing animal ration with choline chloride did not significantly affect all nutrients' digestibility and feeding value. The animals supplemented with 30 g choline chloride recorded significantly higher (P=0.037) total serum protein concentration compared to the other groups. The group received a ration supplemented with 30 g of choline chloride and recorded significantly higher final weight, total gain, and mean daily gain. Data showed significant improvement in TDN, CP and DCP conversion for the animal received ration supplemented with 30 g choline chloride compared to the control group. In conclusion, supplementing fattening calves' ration with rumen-protected choline could improve average daily gain and feed conversion.
Mostrar más [+] Menos [-]Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Asmaa Elhosieny | Mona Zayed | Shawky Selim | Ayman Yassen | Norhan Abdel Aziz
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It can enhance plant productivity. It acts as a mineral dissolution and growth promoter for plants under salt-stress conditions. The selected isolates revealed the general morphological and biochemical characteristics of Stenotrophomonas sp. All the isolates exhibited the highest growth density after 15 hr. at 30oC, resistance to different levels of salinity, different pH levels, and different temperature degrees. Also, the isolates revealed their capabilities to solubilize phosphorus and potassium and to produce different phytohormones. The isolate X.M9 exhibited the highest growth performance in the form of 1.376,1.326,1.292,1.053 and 1.059 OD in most salts’ concentrations compared to all tested isolates respectively. In addition, it (X.M9) exhibited the highest resistance to low temperatures 10 and 15oC being 0.917 and 1.354 OD respectively. The isolate X.M9 recorded the highest IAA of 83.73 mg/100ml compared to all the tested isolates. The isolate X.M9 was identified using 16 SRNA sequencing and submitted to the GenBank database un-der accession number No: OP050187 as Stenotrophomonas rhizophila.
Mostrar más [+] Menos [-]Production of Functional Ice Cream Using Camel Milk Fat Fractions
2023
Alaa Abutaha | Gehan Hussein | Marwa Desouky | Rezk Awad
This work aims to examine the quality features of functional cam-el ice cream (8% fat) prepared by replacing the cream with a solid milk fat fraction (SMF), a liquid milk fat fraction (LMF) and LMF: SMF (2:1 v/v) in the ice cream mixtures. All samples were assessed for their physiochemical and rheological characteristics and the sensory quality of the ice cream mixtures and resulting ice cream. The results clarified that the type of milk fat fraction affected the viscosity of the ice cream mixtures. Also, the whipping ability decreased gradually with the increasing slip melting point of the fraction used. The use of SMF in the ice cream mix decreased the adsorption of protein and fat destabilization, characterized by the slowest melting compared to ice cream with other milk fat sources. The highest and lowest hardness values were found in ice cream mixtures made with SMF and LMF, respectively. In conclusion, ice cream was successfully made by replacing the milk cream fat fractions. Cream substitution with SMF followed by LMF: SMF (2:1 v/v) is recommended in arid and semi-arid regions and improved the whipping ability, overrun, and flavor scores, which were lower when using SMF.
Mostrar más [+] Menos [-]Phylogenetic Evolution of Egyptian Goat Breeds “Capra Hircus” Based on Mitochondrial DNA D-Loop Sequence
2023
Eslam Bherey | Heba Hassan | Adel Ellbadawy | Mahmoud El_Maghraby | Mona Moghazee
The population genetic and molecular evidence of the Arabian goat breed's phylogenetic standing (Capra hircus) is misunderstood, and little is known about genetic diversity in this species. Despite their importance in producing meat and milk, as well as their capacity to endure difficult conditions with little access to food and water, goats are the most common animal in Arab countries. We investigated the phylogenetic history and demographics of domestic goats by sequencing a hypervariable segment of the mtDNA reference region for Baladi, Demuscous, and Zaraibi breeds, as well as sequences retrieved from 16 Arab countries. Three significantly divergent lineages associated with Africa and the Middle East were identified through phylogenetic analysis of the investigated strains of Egyptian goats' mtDNA D-loop region. All Egyptian goats were allocated to lineage A, which is made up of 445 different haplotypes, including Egyptian and Arabian goats. Diversity in haplotypes and in nucleotides for each Arabian goat population was calculated separately and estimated to be 0.99835 and 0.02576, respectively. Finally, we suggest that all goat lineages descend from a single clan. The ancient world's migration and travel may have influenced goat diversity, implying that goats had multiple matrilineal forebears
Mostrar más [+] Menos [-]Molecular Genetic Studies on Honeybees in Response to Some Environmental Stresses
2023
Rehab Mohamed | Naglaa Ebeed | Khalid Fahmy | Naima Alsenosy | Sawsan Abdelmegeed
The honeybee, Apis mellifera, is a widespread pollinator insect. Colony collapse disorder (CCD) has recently caused a significant decline in honeybee numbers worldwide. The beekeeping industry, agriculture, and world biodiversity are threatened by the honeybee population decline. We examined the mRNA levels of heat shock protein gene 60 (hsp60), acetylcholinesterase 1, and acetylcholinesterase 2, as biomolecular markers of the insect response to three separate forms of environmental stress, including high temperature, low temperature, and insecticide. The obtained results indicated increased levels of hsp60 and acetylcholinesterase 2 after the exposure of worker bees to temperatures of 17, 32, and 40°C for one hour, as well as exposure to a low dose of pesticide for 24 h ingestion of imidacloprid solution (2 ppm); meanwhile, acetylcholinesterase 1 showed remarkable expression decrease under heat and cold stresses but increased under pesticide treatment. The responses of honeybees to hsp60, acetylcholinesterase 1, and acetylcholinesterase 2 are diverse and very specific to various stimuli. According to this research, the distinct expression profiles of hsp60 and acetylcholinesterase 2 can serve as useful instruments for tracking honeybees' vulnerability to varied environmental effects. Due to its insufficient responsiveness, acetylcholinesterase 1 expression is not permitted for use as a biomarker.
Mostrar más [+] Menos [-]Decreasing of Monosaccharide Contents Resulted From Cold- Induced Sweetening in Tetraploid Potato (Solanum tuberosum L.) Using Genome Editing
2023
Sally Hassan | Mohamed Abdel-Salam | ayman hanfy | Haytham Abd-Elhalim | Nouh Ahmed | Emad Metry
Worldwide, potato (Solanum tuberosum L.) is one of the most essential agro-economically food crops. To ensure its presence throughout the year for food processors and to extend its shelf life, it should be stored in cold temperatures. Despite the benefits of storage at low temperatures, it causes undesirable phenomena; one of them is cold-induced sweetening, which reduces the quality and the commercial value of the potato tubers. In this study, the CRISPR technology ″Clustered Regularly Interspaced Short Palindromic Repeats″ has been used in potato cultivar Desiree via Agrobacterium mediated transformation to edit starch phosphorylase gene that is responsible for starch degradation in cold temperature storage, after regeneration steps. The regenerated plants were used in the screening of genome editing by Sanger sequencing and the ICE program. Screening results showed that Desiree 2 (DE2), Desiree 7 (DE7) and Desiree 27 (DE27) lines have mutations in sgRNA sequence that indicated a significant reduction in reduced sugar contents of tubers after cold storage for 90 and 120 days. The reduction mean values were 29.224, 35.078 and 35.862 in DE2, DE7 and DE27 respectively after 90 days and 83.212, 56.674 and 34.109 after 120 days without visible differences in plant morphology and tubers
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