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1.
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
2.
Chemosphere ; 271: 129321, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33434829

RESUMO

Sclerotium rolfsii is a soil-borne fungus that causes big losses in productivity of various plant species including Phaseolus vulgaris L. The objectives of this study were to (1) evaluate the impacts of Sclerotium rolfsii on growth and production of common bean plants, (2) determine the effects of Sclerotium rolfsii on nutritive contents of beans, and (3) test the efficacy of bio-inoculants on suppressing plant infection with Sclerotium rolfsii. To fulfill these objectives, we used a coupled pot and field experimental approaches during two growing seasons. Common beans were inoculated with either arbuscular mycorrhizal fungi (Claroideoglomus etunicatum), Saccharomyces cerevisiae, or Trichoderma viride solely or in different combinations. Non-inoculated plants and fungicide treated ones were considered as reference treatments. Throughout these experiments, minimal amounts of rock phosphate were added during soil preparation for bio-inoculated treatments, while the non-inoculated reference treatments received a full dose of P as calcium superphosphate. Results revealed that all tested bioinoculants significantly raised the activities of plant defense enzymes i.e. chitinase, peroxidase and polyphenoloxidase as compared to non-inoculated control. Likewise, pre-, post- and plant survival percentages significantly increased due to these bio-inoculations. Increased survival percentages were attributed to the concurrent increases in uptake of N, P and Zn nutrients by plants treated with bioinoculants. In this concern, plant nutrients uptake was higher in combined than single bio-inoculant treatments. Moreover, the uptake values of plant nutrients owing to the combined bio-inoculants were higher than the corresponding ones achieved due to fungicide treatment. In conclusion, application of the tested bio-inoculants, especially the combined ones can be considered an eco-friendly approach that not only enhances plants resistance against infection with Sclerotium rolfsii but also improves plant nutritive status.


Assuntos
Phaseolus , Basidiomycota , Argila , Fungos , Hypocreales , Doenças das Plantas , Solo
3.
Environ Sci Pollut Res Int ; 26(21): 21849-21857, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31134549

RESUMO

Incorporation of organic amendments is one of the most eco-friendly and economic strategies for the restoration of contaminated soils through diminishing mobility and bioavailability of heavy metals in these soils. This study was carried out under field conditions during the summer season of 2017 on a clay loam soil naturally polluted with Cd (7.61 mg kg-1) due to successive irrigations with wastewater. The main goal of this study was to evaluate the influence of sugarcane bagasse-derived biochar (SBDB) at different rates on fractionation of Cd in soil and its implications on the growth of soybean and concentrations of Cd within the different plant parts. Incorporation of SBDB into the chosen contaminated soil caused noticeable changes in soil pH, electrical conductivity and organic matter, especially with increasing the rate of application. Immobilization of Cd in the used soil was highly influenced by soil properties. According to the sequential extraction procedure, application of SBDB had an efficient role in reducing the soluble/exchangeable fraction. Moreover, it declined both the reducible and oxidizable forms of Cd. The dry weight of soybean organs (roots, seeds, and straw) improved significantly with SBDB additions. The highest dry weight values of straw and seeds for soybean plants were recorded when the soil was treated with SBDB at rates of 15 and 30 t ha-1. Concentrations of Cd in straw and seeds of soybean were markedly affected by its availability in the soil. They decreased from 2.77, 0.96, and 0.62 mg kg-1 at the control treatment (CK) to 1.75, 0.47, and 0.20 mg kg-1 at B4 treatment (30 t SBDB) ha-1 in roots, straw, and seeds of soybean, respectively. In conclusion, the use of SBDB showed high efficiency in the amelioration of Cd-polluted soils and in decreasing Cd toxicity on soybean plants.


Assuntos
Agricultura/métodos , Cádmio/toxicidade , Carvão Vegetal/química , Glycine max/efeitos dos fármacos , Poluentes do Solo/toxicidade , Disponibilidade Biológica , Cádmio/química , Cádmio/farmacocinética , Celulose/química , Argila/química , Egito , Raízes de Plantas/química , Caules de Planta/química , Saccharum/química , Solo/química , Poluentes do Solo/química , Poluentes do Solo/farmacocinética , Glycine max/crescimento & desenvolvimento
4.
Ecotoxicol Environ Saf ; 171: 539-548, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30641315

RESUMO

Extensive use of fertilizers and pesticides led to dangerous ecological effects and therefore the biological approaches have been widely recommended to prevent further deterioration for the environment. The current study was conducted to explore the potentiality of using single or combined inoculations by mycorrhizae, Bacillus subtilis and Pseudomonas fluorescence for controlling the infection of common bean plants with Sclerotium rolfsii on one hand and as bio-fertilizers for improving plants nutritional status on the other hand. The soil of study was mildly infected with S. rolfsii and contained high total-P content. Thus, minimal P inputs were added to the inoculated soil in the form of rock phosphate. Activities of plant defense enzymes i.e. chitinase, peroxidase and polyphenol oxidase were determined under the greenhouse conditions and the results obtained herein indicated that activities of such enzymes increased significantly owing to bio-agent inoculations. In this concern, combined treatments resulted in further significant increases over the single ones. A field study was then conducted for two successive years and the results reveal that single inoculations increased straw and green pod yields as well as the uptake of P and Fe by plants as compared with the non-inoculated treatment. Combined inoculants recorded further significant increases in these parameters even when compared with the fungicide treated plants. Generally, straw and pod yields obtained from the second growing season were significantly higher than those attained in the first growing one. Our study confirms the success of the used bio-treatments in minimizing soil pollution through fertilizer and/or pesticide inputs.


Assuntos
Basidiomycota/patogenicidade , Micorrizas/fisiologia , Phaseolus/crescimento & desenvolvimento , Microbiologia do Solo , Bacillus subtilis/fisiologia , Agentes de Controle Biológico , Fertilizantes , Phaseolus/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Pseudomonas fluorescens/fisiologia , Solo/química , Poluentes do Solo/análise
6.
Ecotoxicol Environ Saf ; 162: 348-353, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30005408

RESUMO

The current study aims to investigate the implications of amending a soil contaminated with Cd with peanut residues biochar (BP) solely or in combination with cow manure (CMPB) at different rates on phytotoxicity of Cd for wheat plants and its distribution in a mine contaminated soil. Soil pH and EC increased progressively in soils amended with either PB or CMPB. Exchangeable Cd was decreased while its non-exchangeable fractions were increased. Dry weights of wheat straw, roots and grains increased when soils amended with either PB or CMPB, especially at the higher application rate. Such increases were correlated significantly with the extractable soil-Cd. Concentrations of Cd in roots were higher than those in straw; whereas, the concentrations in grains seemed to be the lowest. Generally, values of bio-concentration and translocation factors did not exceed "1" and decreased with application of either PB or CMPB. In conclusion, enriching biochar with cow manure is a recommended strategy to reduce Cd uptake and translocation to straw and seeds. Moreover, Concentrations of Cd did not exceed the permissible levels in grains when soils amended with the highest rate of CMPB.


Assuntos
Cádmio/química , Carvão Vegetal , Esterco , Poluentes do Solo/química , Solo/química , Triticum/química , Animais , Cádmio/análise , Bovinos , Fracionamento Químico , Recuperação e Remediação Ambiental/métodos , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Poluentes do Solo/análise , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
7.
PLoS One ; 10(3): e0120809, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25799531

RESUMO

Huperzine A is important in the treatment of Alzheimer's disease. There are major challenges for the mass production of huperzine A from plants due to the limited number of huperzine-A-producing plants, as well as the low content of huperzine A in these plants. Various endophytic fungi produce huperzine A. Colletotrichum gloeosporioides ES026 was previously isolated from a huperzine-A-producing plant Huperzia serrata, and this fungus also produces huperzine A. In this study, de novo RNA sequencing of C. gloeosporioides ES026 was carried out with an Illumina HiSeq2000. A total of 4,324,299,051 bp from 50,442,617 high-quality sequence reads of ES026 were obtained. These raw data were assembled into 24,998 unigenes, 40,536,684 residues and 19,790 genes. The majority of the unique sequences were assigned to corresponding putative functions based on BLAST searches of public databases. The molecular functions, biological processes and biochemical pathways of these unique sequences were determined using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) assignments. A gene encoding copper amine oxidase (CAO) (unigene 9322) was annotated for the conversion of cadaverine to 5-aminopentanal in the biosynthesis of huperzine A. This gene was also detected in the root, stem and leaf of H. serrata. Furthermore, a close relationship was observed between expression of the CAO gene (unigene 9322) and quantity of crude huperzine A extracted from ES026. Therefore, CAO might be involved in the biosynthesis of huperzine A and it most likely plays a key role in regulating the content of huperzine A in ES026.


Assuntos
Alcaloides/biossíntese , Colletotrichum/genética , Colletotrichum/metabolismo , Perfilação da Expressão Gênica , Genes Fúngicos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Amina Oxidase (contendo Cobre)/genética , Colletotrichum/enzimologia , Ontologia Genética , Repetições de Microssatélites/genética , Anotação de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sesquiterpenos
8.
Bull Environ Contam Toxicol ; 90(2): 260-3, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23242260

RESUMO

Dissipation of penconazole was estimated in peach, plum, apricot, and mango fruits cultivated in different farms using QuEChERS method for sample preparation and High performance liquid chromatography with diode array detector. Following one application of normal dose 25 mL 100 L(-1) water, the average initial deposits of penconazole were observed to be 0.44, 0.35, 0.66 and 1.12 mg kg(-1) for peach, plum, apricot, and mango, respectively. The residues dissipated below the maximum residues limit of 0.1 mg kg(-1) after 15, 7, 10 and 21 days for peach, plum, apricot, and mango, respectively. The half-life value (T(1/2)) and pre-harvest interval of penconazole were 7.2 (12), 2.48 (12), 1.53 (7) and 4.54 (21) days for peach, plum, apricot, and mango, respectively. Thus, a waiting period of 21 days was suggested for the safe consumption of penconazole treated mango.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/metabolismo , Fungicidas Industriais/farmacocinética , Espectrofotometria Ultravioleta/métodos , Triazóis/farmacocinética , Calibragem
9.
Bull Environ Contam Toxicol ; 89(4): 873-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22878863

RESUMO

Dissipation of penconazole was estimated in tomatoes fruits cultivated in field using QuEChERS method for sample preparation and high performance liquid chromatography with diode array detector. Following one application of normal dose 25 mL 100 L(-1) water, the average initial deposits of penconazole were observed to be 0.74 and 1.21 mg kg(-1) for tomatoes fruits and soil, respectively. The residues dissipated below the maximum residues limit of 0.2 mg kg(-1) after 15 days. The half-life value (T1/2) and preharvest interval of penconazole were 5.61 and 15 days, respectively. While (T1/2) of penconazole in soil was 15.51 days. Thus, a waiting period of 15 day was suggested for the safe consumption of penconazole treated Tomatoes.


Assuntos
Inseticidas/análise , Resíduos de Praguicidas/análise , Solo/química , Solanum lycopersicum/química , Triazóis/análise , Meia-Vida , Poluentes do Solo/análise
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