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Isolation and Characterization of Native Entomopathogenic Fungi and Their Pathogenicity Against Cowpea aphid
2024
Alyaa Elsawy | mohamed elzemaity | Yosra Ahmed | Walaa Abdelghany
The research aimed to isolate and characterize local entomopathogenic fungi from different agricultural ecosystems and assess their pathogenicity against cowpea aphid. Forty soil samples were collected from different ecosystems. In total, 38 fungal isolates were collected from the cadavers' exteriors of Galleria mellonella larvae. Microscopic observation of these fungal isolates revealed that they belonged to nine fungal genera among them Metarhizium sp. (3 isolates) and Beauveria sp. (5 isolates). Primary experiments showed different bioactivities of the isolates of the two selected genera against the target insect. Only Metarhizium isolates (M3 & M5) and Beauveria isolates (B1 & B5) were selected for further investigations. Identification of fungal cultures by morphological characters, molecular characterization, ITS sequencing, and NCBI Blast showed that two isolates were confirmed as M. anisopliae and two isolates as B. bassiana. The bioassay evaluation revealed that M. anisopliae (M3 and M5) and B. bassiana (B1) exhibited significant virulence against A. craccivora, as evidenced by their high LT50 and LC50 values and substantial sporulation on the cadavers. Therefore, they could be used for the formulation of pesticides targeting this pest on cowpea and other vegetable crops.
显示更多 [+] 显示较少 [-]Frequency Incidence of Tomato Chlorosis Virus and Tomato Yellow Leaf Curl Virus Affecting Tomato Plants
2024
Wael El-Araby | Ahmed Al Attar | Baadawi Othman | Khaled Eldougdoug
The Tomato Chlorosis Criniviruses (ToCV) and Tomato yellow leaf curl Geminivirus (TYLCV), which naturally infecting and limited to the phloem, have caused a drastic reduction in tomato yield. The current study aims to determine the incidence of single and mixed viruses using biological, serological and molecular PCR methods in natural tomato plants. The incidence of mixed infection was found more frequently, followed by ToCV and TYLCV (42.3, 28.8, 17.8 in 2020 and 49.1, 29.7 and 19.1% in 2021, respectively). ToCV causes chlorosis, TYLCV causes leaf curl and yellowing, while mixed ToCV & TYLCV cause progress symptoms. By using the heat shock protein 70 (HSP70) and coat protein (CP) genes, ToCV and TYLCV isolates could be identified. These isolates were recorded in GenBank under accession codes "ON951644.1" and "OP265136.1" respectively. Host plants responded differently to severe and common disease density between ToCV and TYLCV. The transmitted whitefly could distinguish between ToCV and TYLCV within 15-20 minutes of the acquisition period. ToCV increases in fields with high whitefly populations, requiring further research to understand effects and reduce harm.
显示更多 [+] 显示较少 [-]Glutathione-S-Transferase Response Towards Imidacloprid in Honeybees (Apis mellifera L.)
2024
Hussein Ali | Basma Abdel-Aty | Walaa El-Sayed | Faiza Mariy | Gamal Hegazy
Imidacloprid is a systematic neonicotinoid widely used to combat piercing-sucking insects; however, neonicotinoids, despite having low effects on vertebrates, showed high adverse effects on honeybees (Apis mellifera L.). Glutathione-S-transferases (GST) are an important constituent of the defense system in detoxifying invading chemicals. This work examines the effects of imidacloprid on GST activity in vivo and in vitro conditions. Results revealed that there are two responses of GST activity toward IMI treatment; first, stimulation of enzyme activity to combat and detoxify the insecticide. Second, direct inhibition of GST, which is confirmed by the in vitro inhibition with IC50 887.42 ppm. At a short exposure time to IMI (2 hours) at an IMI concentration of 0.35 ppm, the enzyme was stimulated up to 113% while increasing exposure time or IMI concentration, the inhibition effect dominates.
显示更多 [+] 显示较少 [-]Some Natural and Chemical Compounds Directly Affect Pests of Mulberry Trees and Their Side Effects on Silkworm Larvae
2024
Mai Hassanein | Youssef Abdalla | Sawsan Abdelmegeed
Mulberry trees suffer from many pest infestations. To control these pests, some natural compounds such as Techno Oil and Top 9 and some other chemicals such as Mospilan® and Chinook® were used. Mulberry trees, Morus nigra were treated with three different concentrations of each of Chinook, Techno Oil® and Top 9® to reduce infestation with Icerya sp. and Ferrisia virgate. A high reduction rate of more than 90% occurred when using these pesticides. On the other hand, the corrected mortality of mulberry silkworm larvae was 93.3%, 0.0% and 6.7% respectively after 8 days of treatment. When treating mulberry trees Morus alba with two different concentrations of each of pesticides; Mospilan and Techno Oil against whitefly, the average rate of infestation reduction was 100% and 94.94%, respectively. The corrected mortality of mulberry silkworms' larvae was 100% and 0.0% after 8 days of treatment respectively. This study proved that natural compounds could be used safely instead of chemical pesticides to reduce the pest population without affecting the life of silkworm larvae or cocoon properties.
显示更多 [+] 显示较少 [-]Impact of Organic, NPK and Biofertilization on Yield of Cowpea Cultivars Under Arid Land Conditions
2024
Dalia Soliman
This study was conducted to investigate the effects of organic, NPK, and biofertilizers on the yield of two cowpea varieties grown under arid land conditions. Two cultivars of cowpea (Karim-7 and Dokki-331) were evaluated using different fertilizer types. The fertilizers examined were organic (farmyard manure (FYM) and chicken manure (CHM)) and biofertilizers (effective microorganisms (EM1) and technology of smart fertilizer (TS)) in addition to NPK treatments (NPK (50 kg/fed), NPK (100 kg/fed), EM1 (15 m3.fed-1) + NPK (50 kg/fed), TS (15 m3.fed-1) + NPK (50 kg/fed). A randomized complete block design (RCBD) with 16 treatments and three replications was used to set up the experiment. The measured yield parameters were seed number/plant, pod length, seed number/pod, pod number/plant, dry yield/plant, dry yield/m2, bio yield, pod weight, 100-seed weight, and grain yield. The results cleared that the cultivar dokki-331 under EM1 biofertilizer + NPK (50 kg/fed) combination treatment was the superior practice for increasing all studied traits.
显示更多 [+] 显示较少 [-]In vitro, Evaluation of Organic and Mineral Treatments Against Potato Black-leg Disease (Pectobacterium atrosepticum)
2024
Sondos Nagdy | Afaf El-Meneisy | Naglaa Balabel | Nagy Abd El-Ghaffar
Potato (Solanum tuberosum L.) is considered one of the main food crops in many countries worldwide. The present work was planned to manage potato black-leg disease using organic treatments as well as mineral-nitrogenous treatments, in addition to examining their effects on the pathogenic bacterium (Pectobacterium atrosepticum) population under artificial inoculation conditions. The obtained data indicated that applications of cabbage, onion and peppermint dry ground leaves as organic matters, and applications of ammonium super-phosphate, potassium sulfate and urea as mineral-nitrogenous fertilizers reduced P. atrosepticum population and black-leg disease of potato compared with the control treatment. In addition, these treatments led to increasing potato yield, while the beneficial effects increased with increasing their doses compared with the control treatment. Meanwhile, the organic matter appeared highly effective compared with mineral-nitrogenous fertilizers in disease reduction. However, mineral-nitrogenous fertilizers appeared highly effective in increasing potato yield. Meanwhile, onion dry ground leaves (organic matter) and urea (nitrogenous fertilizer) were the most effective on the pathogenic bacterium population and severity of the disease compared with other treatments
显示更多 [+] 显示较少 [-]Evaluation of Biologically Treated Olive Mill Wastewater for Irrigation of Pea Plant
2023
Rokia yehia | Azza Abdelaal | Ahmed Abdelhafez
This study evaluated the use of biologically treated olive mill wastewater (OMWW) for irrigation of pea plants, rather than discharging this nutrient-rich liquid and polluting the environment. Pea seeds were planted in pots containing soil irrigated with tap water (control), untreated (crude) OMWW, or OMWW treated with the fungus, Pleurotus columbinus, or algae Spirulina platensis or Wollea sp., with two NPK rates. Plant length shoot and root dry weight, nitrogen, phosphorus, potassium, chlorophyll, and carotene contents were measured, along with to nitrogenase and dehydrogenase activity. The highest shoots' N and P contents were recorded in plants irrigated with Sp. platensis- treated OMWW + 100% NPK; while the highest K content was in plants irrigated with crude OMWW + 100% NPK. The highest dehydrogenase activity, 59.01 μg TPF/100 g soils, was recorded in plants irrigated with P. columbinus-treated OMWW supported with 75% NPK, while maximum nitrogenase activity (261.82 μmol/100g soil/day) occurred in plants irrigated with Wollea sp.-treated OMWW with 75% NPK. The highest content of chlorophylls a & b and carotene (0.838, 0.276, 0.252 mg/g dry weight, respectively) were found in plants irrigated with OMWW treated with Wollea sp. and 100% NPK. Thus, biologically-treated OMWW showed promising impacts on plant growth parameters.
显示更多 [+] 显示较少 [-]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
显示更多 [+] 显示较少 [-]The Relationship Between Vegetation Type and Population Density-Diversity of Spiders in Certain Vegetable Crops
2023
Hamdi Abd El-Karim | Marguerite Rizk
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.
显示更多 [+] 显示较少 [-]Morphological and Molecular Identification of Penicillium digitatum Causing Green Mould of Citrus Fruits in Egypt
2023
Abdalrahman Desouki | Labiba Ahmed Reda | Mohamed Rashed | 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
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