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1.
PeerJ ; 12: e16870, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38563014

RESUMO

The brinjal fruit and shoot borer (BFSB), Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), is a very detrimental pest that causes significant economic losses to brinjal crop worldwide. Infested brinjal fruits were collected from vegetable fields located at the ICAR-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India, during two consecutive seasons (2021-2022). The larvae of the pest were brought to the laboratory and reared under controlled conditions of 25 ± 0.5 °C and 70 ± 5% relative humidity, for the emergence of parasitoids. In addition, the survey of Hymenoptera parasitoids in brinjal was conducted utilizing a sweep net and yellow pan trap over the course of two seasons. The results reveal that five parasitoid species were emerged from L. orbonalis viz., Apanteles hemara Nixon, 1965, Bracon greeni Ashmead 1896 (Hymenoptera: Braconidae), Goryphus nursei (Cameron, 1907), Trathala flavoorbitalis (Cameron, 1907) (Hymenoptera: Ichneumonidae) and Spalangia gemina Boucek 1963 (Hymenoptera: Spalangiidae). Out of these, A. hemara and S. gemina were documented as new occurrences in Delhi. Additionally, A. hemara was recorded for the first time as a parasite on L. orbonalis. Trathala flavoorbitalis was observed during both seasons and exhibited higher parasitism reaching 15.55% and 18.46% in July and August 2022, respectively. However, the average parasitism (%) recorded by A. hemara, B. greeni, G. nursei, T. flavoorbitalis and S. gemina was 3.10%, 1.76%, 1.10%, 9.28% and 1.20% respectively. Furthermore, the findings showed a significant (p ≤ 0.01) strongly positive correlation between fruit infestation (%) by L. orbonalis and parasitism (%). The survey indicates the presence of a broad group (19 families and 60 species) of Hymenoptera parasitoids in the brinjal crop ecosystem in Delhi which could be valuable in biological control. In light of these results, this study revealed that A. hemara and other parasitoids identified in this study alongside T. flavoorbitalis would be ideal biocontrol agents within the integrated pest management (IPM) program of BFSB in Delhi.


Assuntos
Himenópteros , Mariposas , Solanum melongena , Humanos , Animais , Solanum melongena/parasitologia , Ecossistema , Complexo Ferro-Dextran , Mariposas/parasitologia , Biodiversidade
2.
Biodivers Data J ; 12: e115845, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481856

RESUMO

The migratory locust, Locustamigratoria (L.), a significant grasshopper species known for its ability to form large swarms and cause extensive damage to crops and vegetation, is subject to the influence of climate change. This research paper employs geographic information system (GIS) and MaxEnt ecological modelling techniques to assess the impact of climate change on the distribution patterns of L.migratoria. Occurrence data and environmental variables are collected and analysed to create predictive models for the current and future distribution of the species. The study highlights the crucial role of climate factors, particularly temperature and precipitation, in determining the locust's distribution. The MaxEnt models exhibit high-performance indicators, accurately predicting the potential habitat suitability of L.migratoria. Additionally, specific bioclimatic variables, such as mean temperature and annual precipitation, are identified as significant factors influencing the species' presence. The generated future maps indicate how this species will invade new regions especially in Europe. Such results predict the risk of this destructive species for many agriculture communities as a direct result of a warming world. The research provides valuable insights into the complex relationship between locust distribution and environmental factors, enabling the development of effective strategies for locust management and early warning systems to mitigate the impact on agriculture and ecosystems.

3.
Plants (Basel) ; 13(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276766

RESUMO

Sugar beet root rot disease triggered by Fusarium oxysporum f. sp. radicis-betae is a destructive disease and dramatically affects the production and quality of the sugar beet industry. Employing beneficial microorganisms as a biocontrol strategy represents an eco-friendly and sustainable approach to combat various plant diseases. The distinct aspect of this study was to assess the antifungal and plant growth-promoting capabilities of recently isolated Streptomyces to treat sugar beet plants against infection with the phytopathogen F. oxysporum. Thirty-seven actinobacterial isolates were recovered from the rhizosphere of healthy sugar beet plants and screened for their potential to antagonize F. oxysporum in vitro. Two isolates SB3-15 and SB2-23 that displayed higher antagonistic effects were morphologically and molecularly identified as Streptomyces spp. Seed treatment with the fermentation broth of the selected Streptomyces strains SB3-15 and SB2-23 significantly reduced disease severity compared to the infected control in a greenhouse experiment. Streptomyces SB2-23 exhibited the highest protective activity with high efficacy ranging from 91.06 to 94.77% compared to chemical fungicide (86.44 to 92.36%). Furthermore, strain SB2-23 significantly increased plant weight, root weight, root length, and diameter. Likewise, it improves sucrose percentage and juice purity. As a consequence, the strain SB2-23's intriguing biocontrol capability and sugar beet root growth stimulation present promising prospects for its utilization in both plant protection and enhancement strategies.

4.
Insects ; 14(2)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36835689

RESUMO

Spogostylum ocyale (Wiedemann 1828) is a large robust species of bee fly (family Bombyliidae), known to be a larval ectoparasitoid as well as an important flower pollinator as an adult. This species has become extremely rare or has disappeared from many of its historic habitats due to substantial changes in floral and faunal compositions in recent years. Climate change and urbanisation, together with other anthropogenic activities, may be to blame for these changes. Distribution modelling based on environmental variables together with known occurrences is a powerful tool in analytical biology, with applications in ecology, evolution, conservation management, epidemiology and other fields. Based on climatological and topographic data, the current and future distributions of the parasitoid in the Middle East region was predicted using the maximum entropy model (Maxent). The model performance was satisfactory (AUC mean = 0.834; TSS mean = 0.606) and revealed a good potential distribution for S. ocyale featured by the selected factors. A set of seven predictors was chosen from 19 bioclimatic variables and one topographic variable. The results show that the distribution of S. ocyale is mainly affected by the maximum temperature of the warmest period (Bio5) and temperature annual range (Bio7). According to the habitat suitability map, coastal regions with warm summers and cold winters had high to medium suitability. However, future scenarios predict a progressive decline in the extent of suitable habitats with global climate warming. These findings lead to robust conservation management measures in current or future conservation planning.

5.
Parasitol Res ; 121(12): 3467-3476, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36136139

RESUMO

Rhipicephalus annulatus is a tick species of veterinary importance due to its potential to transmit babesiosis to cattle. This species has a Holarctic distribution with some Afrotropical records and is one-host species of veterinary importance. This study was carried out from September 2021 to February 2022 at 6 Egyptian collection sites, and a total of 1150 cattle were scanned randomly to collect ticks. A total of 1095 tick specimens were collected and identified as R. annulatus using taxonomic keys. Males were found on all parts of the cattle except the head and around the eyes, but females were found on all parts; in addition, the highest number of specimens was gathered from the udder, (neck and chest), and belly. Maximum entropy (MaxEnt) modeling was used to predict the potential global distribution of R. annulatus. The MaxEnt model performed better than random with an average test area under the curve (AUC) value of 0.96, and model predictions were significantly better than random and gave (AUC) ratios above the null expectations in the partial receiver operating characteristic (pROC) analyses (P < 0.001). Based on correlation analyses, a set of 9 variables was selected for species from 15 bioclimatic and 5 normalized difference vegetation index (NDVI) variables. The study showed that the current distribution of R. annulatus is estimated to occur across Asia, Africa, Europe, South America, and North America. Annual mean temperature (Bio1) and median NDVI had the highest effect on the distribution of this species. The environmentally suitable habitat for R. annulatus sharply increased with increasing annual mean temperature (Bio1). These results can be used for making effective control planning decisions in areas suitable to this vector of many diseases worldwide.


Assuntos
Anaplasmose , Babesiose , Doenças dos Bovinos , Ixodidae , Rhipicephalus , Infestações por Carrapato , Feminino , Masculino , Bovinos , Animais , Ecossistema , Doenças dos Bovinos/prevenção & controle , Infestações por Carrapato/veterinária
6.
Molecules ; 27(10)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35630573

RESUMO

The house fly Musca domestica L. is one of the medical and veterinary pests that can develop resistance to different insecticides. Mixing insecticides is a new strategy for accelerating pest control; furthermore, it can overcome insect resistance to insecticides. This study aims to evaluate three insecticides, chlorfenapyr, abamectin, and lambda-cyhalothrin, individually and their binary mixtures against 2nd instar larvae of M. domestica laboratory strain. Chlorfenapyr exhibited the most toxic effect on larvae, followed by abamectin then the lambda-cyhalothrin. The half-lethal concentrations (LC50) values were 3.65, 30.6, and 94.89 ppm, respectively. These results revealed that the high potentiation effect was the mixture of abamectin/chlorfenapyr in all the mixing ratios. In contrast, the tested combination of lambda-cyhalothrin/abamectin showed an antagonism effect at all mixing ratios against house fly larvae. The total protein, esterases, glutathione-S-transferase (GST), and cytochrome P-450 activity were also measured in the current investigation in the larvae treated with chlorfenapyr. Our results indicate that GST may play a role in detoxifying chlorfenapyr in M. domestica larvae. The highest activity of glutathione-S-transferase was achieved in treated larvae with chlorfenapyr, and an increase in cytochrome P-450 activity in the larvae was observed post-treatment with Abamectin/chlorfenapyr.


Assuntos
Moscas Domésticas , Inseticidas , Animais , Sistema Enzimático do Citocromo P-450 , Glutationa , Resistência a Inseticidas , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Larva , Nitrilas , Piretrinas , Transferases
7.
Insects ; 13(5)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35621818

RESUMO

Beekeeping is essential for the global food supply, yet honeybee health and hive numbers are increasingly threatened by habitat alteration, climate change, agrochemical overuse, pathogens, diseases, and insect pests. However, pests and diseases that have unknown spatial distribution and influences are blamed for diminishing honeybee colonies over the world. The greater wax moth (GWM), Galleria mellonella, is a pervasive pest of the honeybee, Apis mellifera. It has an international distribution that causes severe loss to the beekeeping industry. The GWM larvae burrow into the edge of unsealed cells that have pollen, bee brood, and honey through to the midrib of the wax comb. Burrowing larvae leave behind masses of webs that cause honey to leak out and entangle emerging bees, resulting in death by starvation, a phenomenon called galleriasis. In this study, the maximum entropy algorithm implemented in (Maxent) model was used to predict the global spatial distribution of GWM throughout the world. Two representative concentration pathways (RCPs) 2.6 and 8.5 of three global climate models (GCMs), were used to forecast the global distribution of GWM in 2050 and 2070. The Maxent models for GWM provided a high value of the Area Under Curve equal to 0.8 ± 0.001, which was a satisfactory result. Furthermore, True Skilled Statistics assured the perfection of the resultant models with a value equal to 0.7. These values indicated a significant correlation between the models and the ecology of the pest species. The models also showed a very high habitat suitability for the GWM in hot-spot honey exporting and importing countries. Furthermore, we extrapolated the economic impact of such pests in both feral and wild honeybee populations and consequently the global market of the honeybee industry.

8.
J Fungi (Basel) ; 8(4)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35448627

RESUMO

Herein, silver nanoparticles (Ag-NPs) were synthesized using an environmentally friendly approach by harnessing the metabolites of Aspergillus niger F2. The successful formation of Ag-NPs was checked by a color change to yellowish-brown, followed by UV-Vis spectroscopy, Fourier transforms infrared (FT-IR), Transmission electron microscopy (TEM), and X-ray diffraction (XRD). Data showed the successful formation of crystalline Ag-NPs with a spherical shape at the maximum surface plasmon resonance of 420 nm with a size range of 3-13 nm. The Ag-NPs showed high toxicity against I, II, III, and IV instar larvae and pupae of Aedes aegypti with LC50 and LC90 values of 12.4-22.9 ppm and 22.4-41.4 ppm, respectively under laboratory conditions. The field assay exhibited the highest reduction in larval density due to treatment with Ag-NPs (10× LC50) with values of 59.6%, 74.7%, and 100% after 24, 48, and 72 h, respectively. The exposure of A. aegypti adults to the vapor of burning Ag-NPs-based coils caused a reduction of unfed individuals with a percentage of 81.6 ± 0.5% compared with the positive control, pyrethrin-based coils (86.1 ± 1.1%). The ovicidal activity of biosynthesized Ag-NPs caused the hatching of the eggs with percentages of 50.1 ± 0.9, 33.5 ± 1.1, 22.9 ± 1.1, and 13.7 ± 1.2% for concentrations of 5, 10, 15, and 20 ppm, whereas Ag-NPs at a concentration of 25 and 30 ppm caused complete egg mortality (100%). The obtained data confirmed the applicability of biosynthesized Ag-NPs to the biocontrol of A. aegypti at low concentrations.

9.
Antibiotics (Basel) ; 10(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34680736

RESUMO

BACKGROUND: The Red Sea sponges have been endorsed as a plentiful source of bioactive compounds with promising anti-cancer and anti-inflammatory activities; therefore, exploring their potential as a source of anti-cancer metabolites has stimulated a growing research interest. PURPOSE: To investigate the anti-cancer and anti-inflammatory potential of the Red Sea sponges, in their bulk and silver nanostructure. Metabolomics analysis of the selected sponge followed by molecular docking studies, will be conducted to explore and predict the secondary metabolites that might provide its capability of inhibiting cancer. MATERIALS AND METHODS: We prepared a chloroform extract (CE) and ethyl acetate extract (EE) of the Red Sea sponge Phyllospongia lamellosa synthesized silver nanoparticles. The prepared silver nanoparticles were characterized through UV-vis spectrophotometric, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR) analyses. Testing for their anti-cancer activities was performed against MCF-7, MDB-231, and MCF-10A cells. Anti-inflammatory activity against COX-1 and 2 was assessed. Furthermore, liquid chromatography-mass spectrometry (LC-MS)-based metabolomics analysis and molecular docking were also applied.

10.
Saudi J Biol Sci ; 28(10): 5667-5673, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34588878

RESUMO

OBJECTIVES: The species Palarus latifrons (bee pirates) has been recorded in Saudi Arabia as an invasive species. This pest can destroy honey bee colonies under certain conditions. The origin of this species in Africa and it has a good ability to adapt to desert conditions. Studies on this species are very few but its current distribution in the Arabian deserts is mainly in the Arabian Gulf countries. This study presents maps for the possible expansion of this species to invade other desert areas in the Arabian countries' under current and near-future conditions (2030). METHODS: This pest is a solitary insect with high activity during summer. It is hypothesized that summer conditions and especially temperature are the limiting factor for its distribution in the deserts. The analysis depended on generating maps based on temperatures during summer and based on two bioclimatic factors. Maxent and the geographical information system (GIS) were used to perform the analysis. RESULTS AND CONCLUSIONS: All maps showed the high ability of this pest to spread in the Gulf countries. In North Africa: south Egypt and Libya, and some parts of Algeria showed suitability for Palarus. The invasion of this pest towards North Africa can happen mostly due to trading activities with Gulf countries especially materials containing soil. Continues monitoring for the activity of Palarus in the risk areas is highly advised.

11.
PLoS One ; 13(8): e0201294, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30091982

RESUMO

Drosophila suzukii or spotted wing Drosophila is an economically important pest which can have a devastating impact on soft and stone fruit industries. Biological pesticides are being sought as alternatives to synthetic chemicals to control this invasive pest, but many are subject to degradation either in the environment or in the insect gut and as a result require protection. In this study we identified a sharp change in pH of the adult midgut from neutral to acidic (pH <3), which we then exploited to develop poly(2-vinylpyridine) (P2VP) microcapsules that respond to the change in midgut pH by dissolution and release of their cargo for uptake into the insect. First, we used labelled solid poly(methyl methacrylate) (PMMA) particles to show that microcapsules with a diameter less than 15 µm are readily ingested by the adult insect. To encapsulate water-soluble biological species in an aqueous continuous phase, a multiple emulsion template was used as a precursor for the synthesis of pH-responsive P2VP microcapsules with a fluorescent (FITC-dextran) cargo. The water-soluble agent was initially separated from the aqueous continuous phase by an oil barrier, which was subsequently polymerised. The P2VP microcapsules were stable at pH > 6, but underwent rapid dissolution at pH < 4.2. In vivo studies showed that the natural acidity of the midgut of D. suzukii also induced the breakdown of the responsive P2VP microcapsules to release FITC-dextran which was taken up into the body of the insect and accumulated in the renal tubules.


Assuntos
Agentes de Controle Biológico/administração & dosagem , Proteção de Cultivos/métodos , Drosophila/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Controle de Insetos/métodos , Animais , Cápsulas , Feminino , Frutas , Concentração de Íons de Hidrogênio , Masculino , Microtecnologia , Polimetil Metacrilato/química
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