خيارات البحث
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Description of Leafhopper, Hebata (Alboneurasca) decipiens (Paoli, 1930) and Its Transmitting Phytoplasma Infesting Sugar Beet Plants
2023
Ibrahim, Heba | Abdelrahman Emam, Azza | Bondok, Ahmed | Ahmed, Magdy | Abd-Elraheem, Amro
The second sugar crop of sugar production after sugar cane world-wide is sugar beet (Beta vulgaris L.). 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 detection and molecular identification of Candidatus Phyto-plasma 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.
اظهر المزيد [+] اقل [-]Effect of Foliar Spraying with Pink Pigmented Facultative Methylotrophic Bacteria on the Growth and Productivity of Strawberry
2023
Ismail, shadia | Mohammed, Fafy
Pink-pigmented facultative methylotrophic bacteria (PPFM) isolated from cotton leaves was identified based on phenotypic and genotypic characteristics as Methylobacterium rodiotolerance. Two field experiments were conducted to investigate the effects of PPFM, methanol (10 and 30%) and a combination of bacteria and methanol on the growth, fruit quality, and yield of two strawberry cultivars (Florida and Festival). The main differences between the two cultivars are greater foliage fresh weight and early yield in cv. Florida while Festival cv. had a higher total yield per plant and greater anthocyanins and ascorbic acid contents. The greatest vegetative growth, dry matter percentage, potassium content, and carbohydrate content besides the earliest yield per plant were observed following spraying with PPFM or PPFM mixed with 10% methanol. Spraying with PPFM resulted in the highest total yield per plant, highest yield per feddan, and fruit quality. Spraying cv. Florida with PPFM resulted in the best early yield while spraying cv. Festival with PPFM resulted in the highest total yield and fruit quality. Spraying with PPFM appears to be the most efficient treatment for enhancing the total yield of Festival cv. by an average of 23.02 and 24.06 tons per feddan in the first and second seasons, respectively.
اظهر المزيد [+] اقل [-]Effect of Rumen-Protected Choline Supplementation on Growth Performance of Fattening Calves
2023
Amin, Abdelrahman | marwan, Ahmed | Abdelaziz, Fouad | Elbordiny, Nasr
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 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.
اظهر المزيد [+] اقل [-]Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Elhosieny, Asmaa | Zayed, Mona | Selim, Shawky | Abdel Aziz, Norhan
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It has the capability to 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 30˚C, 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 pro-duce 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. As well 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 were identified using 16 SRNA sequencing and submitted to the GenBank database under accession number No: OP050187 as Stenotrophomonas rhizophila.
اظهر المزيد [+] اقل [-]Isolation and Characterization of Probiotics from Various Food Products as Potential Human Food Additives
2023
Mohamed Ali, Fekria | Abdelhafez, Ahmed | Hassan, Enas | Abd-Elhalim, Basma
In this study, human-safe lactic acid microorganisms (LAM) were isolated from food samples to be used as potential additives for human food. Samples from various food sources (artisanal cheeses, fermented chickpeas, fermented rice, natural yogurt, pickles, and raw milk) were used to inoculate de Man, Rogosa, and Sharpe (MRS) and malt agar plates, which were incubated at 30°C for 48 h or 37°C for 72 h to isolate lactic acid bacteria and yeast, respectively. Out of 120 isolates (85 bacteria and 35 yeast), 75 isolates showed γ-hemolytic activity and were considered “Generally Recognized As Safe” (GRAS) isolates. After testing their growth rate under the gastrointestinal tract (GIT) conditions, including acidic pH and specific bile salt concentrations, we selected 30 isolates. Then, we evaluated the fermentative abilities of these 30 isolates on nine types of carbohydrates, their total acidity, and their antagonistic activity against five human pathogens. Based on the results of these tests, four isolates were selected for identification using the Biolog program and 16S rRNA sequencing for bacteria and 18S rRNA sequencing for yeast and found to be Bacillus bingmayongesis (FJAT-13831),Lacticaseibacillus paracasei (R094), Pediococcus pentosaceus (DSM20336), and one yeast isolate as Saccharomyces cerevisiae (SaCe1 26S).
اظهر المزيد [+] اقل [-]Decreasing of Monosaccharide Contents Resulted From Cold- Induced Sweetening in Tetraploid Potato (Solanum tuberosum L.) Using Genome Editing
2023
Hassan, Sally | Abdel-Salam, Mohamed | hanfy, ayman | Abd-Elhalim, Haytham | Ahmed, Nouh | Metry, Emad
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
اظهر المزيد [+] اقل [-]Role of Vitamin C Supplementation in Alleviation of Aflatoxin-Contaminated Feed of Nile tilapia (Oreochromis niloticus)
2023
El-Nahal, Sara | Amer, Mohamed | Osman, Mohamed | Ahmed, Kareem
The purpose of the research was to illustrate the effects of feeding Nile tilapia fingerlings (Oreochromis niloticus) with low doses of aflatoxins (AFs) with and without vitamin C supplementation to investigate the capacity of vitamin C in detoxification. Ten experimental diets were formulated and divided into three categories. The first category included: T1, T4 and T7 feedings included 20, 40 and 80 μg AFs kg−1 feed respectively, while both the second category T2, T5 and T8 and the third category T3, T6 and T9 were treated with contaminated feed with AFs for 57days then both categories shifted to different regime till the conclusion of the experimentation. The second category was fed uncontaminated feed while the third category was fed a supplemented diet with 100 mg Kg-1 of vitamin C. For 113 days the experiment was conducted. The results showed that shifting from a contaminated diet to an uncontaminated diet (category 2) or adding vitamin C to the contaminated diet (category 3) improved the deterioration that occurred in the values of growth performance, biochemical parameters and histological disorders caused by AFs. Furthermore, the results from the control group were superior to all the treatments.
اظهر المزيد [+] اقل [-]Efficacy of Potassium Fertilizer and Certain Pesticides for the Management of Brinjal Fruit Infection by Shoot Borer [Leucinodes Orbonalis (Guenée)]
2023
bhandari, Sagar | kandel, Bikash | gyawali, Pramod | pokhrel, Saurav | ojha, Sushil | bhandari, Sarita
The research aims to evaluate the efficacy of different levels of potassium fertilizer (8 g/plant K2O) as well as the insecticides neemix, spinosad, and imidacloprid at the rates of 6 ml, 0.33 ml, and 0.33 g/L water, respectively, for the management of brinjal fruits and shoot borer. The two-factor randomized complete block design with three replications was used. Significant minimum shoot damage was recorded in the plots treated with imidacloprid (0%), spinosad (1.67%) and neemix (5.0%) at 81 days after planting. Similarly, a significant minimum fruit infestation (2.90%) was recorded with imidacloprid, which was lower than those of spinosad (15.16%) and neemix (19.63%). The application of potassium fertilizer at a rate of 8 g/plant showed a significant reduction in shoot infestation (2.50%) 81 days after planting. The minimum percentage yield of infested fruit was reported with spinosad (1.03%), which was at par with other insecticidal treatments. Considering the negative impacts of chemical pesticides, neemix 6 ml/L water in combination with potassium fertilizer at 8 g/plant is recommended.
اظهر المزيد [+] اقل [-]Morphological and Molecular Identification of Penicillium digitatum Causing Green Mould of Citrus Fruits in Egypt
2023
Desouki, Abdalrahman | Ahmed Reda, Labiba | Rashed, Mohamed | Shehata, Shehata
Nine Penicillium digitatum isolates were isolated from citrus fruits and tested for their pathogenicity on Navel orange fruit (Citrus sinensis L.). In this regard, the isolates exhibited three different levels of virulence. The isolates were identified morphologically using malt extract agar (MEA) and Czapek yeast extract agar (CYA) for colony characteristics, and MEA for microscopic features. Each one of the isolates has the unique features of P. digitatum, especially the largest conidia (6.1-11.9 µm long X 3.2-8 µm width), and phialides (10.1-21.4 µm long X 4-5.1 µm width). In addition, the isolates were identified on a molecular basis using ITS1 and ITS4 primers to confirm morphological identification. Phylogenetic analysis revealed that there was high variance among the isolates, and there were different relations between some of our isolates and other P. digitatum registered strains originating from different countries all over the world. The sequences were submitted to respective GenBank nucleotide databases with accession No. OR198852, OR198853, OR198854, OR198855, OR198856, OR198857, OR198858, OR198859 and OR198860. We also isolated a new P. digitatum (OB15: OR198859) strain with high virulence and rapid sporulation
اظهر المزيد [+] اقل [-]The Relationship Between Vegetation Type and Population Density-Diversity of Spiders in Certain Vegetable Crops
2023
Abd El-Karim, Hamdi | Rizk, Marguerite
The experiment was carried out on three different vegetable crops, Cucumber Cucumis sativus L. (Cucurbitaceae), eggplant Solanum melongena L. (Solanaceae) and okra Abelmoschus esculentus L. (Malvaceae), during summer 2021, to investigate the effect of vegetation type on spider density and diversity. For this study, the pitfall trap method was used to collect spiders from the soil surface to ensure a comprehensive representation of all spider guilds. During this study, 20 species belonging to 6 families were collected. The results showed that a total of 374, 285 and 194 individuals belonging to 18, 17 and 15 species were recorded in okra, cucumber and eggplant fields respectively. Species diversity was greater in okra cultivation. Results also indicated that the Lycosidae family was the most abundant and dominant, representing 71.75%, followed by the Linyphiidae family of 90 individuals representing 10.55% of the whole obtained population. The most dominant species were Wadicosa fidelis 152, 98 and 67 individuals and Pardosa injucunda 111, 69 and 52 individuals in okra, cucumber and eggplant respectively. It is inferred from this study that the type of plant can have an impact on spider communities.
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