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1.
Sci Rep ; 14(1): 10124, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698114

RESUMEN

Despite the high energetic cost of the reduction of sulfate to H2S, required for the synthesis of sulfur-containing amino acids, some wine Saccharomyces cerevisiae strains have been reported to produce excessive amounts of H2S during alcoholic fermentation, which is detrimental to wine quality. Surprisingly, in the presence of sulfite, used as a preservative, wine strains produce more H2S than wild (oak) or wine velum (flor) isolates during fermentation. Since copper resistance caused by the amplification of the sulfur rich protein Cup1p is a specific adaptation trait of wine strains, we analyzed the link between copper resistance mechanism, sulfur metabolism and H2S production. We show that a higher content of copper in the must increases the production of H2S, and that SO2 increases the resistance to copper. Using a set of 51 strains we observed a positive and then negative relation between the number of copies of CUP1 and H2S production during fermentation. This complex pattern could be mimicked using a multicopy plasmid carrying CUP1, confirming the relation between copper resistance and H2S production. The massive use of copper for vine sanitary management has led to the selection of resistant strains at the cost of a metabolic tradeoff: the overproduction of H2S, resulting in a decrease in wine quality.


Asunto(s)
Cobre , Fermentación , Sulfuro de Hidrógeno , Metalotioneína , Odorantes , Saccharomyces cerevisiae , Vitis , Vino , Vino/análisis , Cobre/metabolismo , Vitis/microbiología , Saccharomyces cerevisiae/metabolismo , Sulfuro de Hidrógeno/metabolismo , Odorantes/análisis , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Sulfitos/farmacología , Control de Plagas/métodos
2.
J Environ Manage ; 359: 121022, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38704958

RESUMEN

Pesticides are critical for protecting agricultural crops, but the off-site transport of these materials via spray drift and runoff poses risks to surface waters and aquatic life. California's Central Coast region is a major agricultural hub in the United States characterized by year-round production and intensive use of pesticides and other chemical inputs. As a result, the quality of many waterbodies in the region has been degraded. A recent regulatory program enacted by the Central Coast Regional Water Quality Control Board set new pesticide limits for waterways and imposed enhanced enforcement mechanisms to help ensure that water quality targets are met by specific dates. This regulatory program, however, does not mandate specific changes to pest management programs. In this study, we evaluate the economic, environmental, and pest management impacts of adopting two alternative pest management programs with reduced risks to surface water: 1) replacing currently used insecticide active ingredients (AIs) that pose the greatest risk to surface water with lower-risk alternatives and 2) converting conventional arthropod pest management programs to organic ones. We utilize pesticide use and toxicity data from California's Department of Pesticide Regulation to develop our baseline and two alternative scenarios. We focus on three crop groups (cole crops, lettuce and strawberry) due to their economic importance to the Central Coast and use of high-risk AIs. For Scenario 1, we estimate that implementing the alternative program in the years 2017-2019 would have reduced annual net returns on average by $90.26 - $190.54/ha, depending on the crop. Increased material costs accounted for the greatest share of this effect (71.9%-95.6%). In contrast, Scenario 2 would have reduced annual net returns on average by $5,628.12 - $18,708.28/ha during the study period, with yield loss accounting for the greatest share (92.8-97.9%). Both alternative programs would have reduced the associated toxic units by at least 98.1% compared to the baseline scenario. Our analysis provides important guidance for policymakers and agricultural producers looking to achieve environmental protection goals while minimizing economic impacts.


Asunto(s)
Agricultura , Control de Plagas , Plaguicidas , California , Agricultura/economía , Control de Plagas/economía , Productos Agrícolas , Calidad del Agua
3.
Sci Total Environ ; 930: 172521, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38641095

RESUMEN

Agricultural practitioners, researchers and policymakers are increasingly advocating for integrated pest management (IPM) to reduce pesticide use while preserving crop productivity and profitability. Using selective pesticides, putatively designed to act on pests while minimising impacts on off-target organisms, is one such option - yet evidence of whether these chemicals control pests without adversely affecting natural enemies and other beneficial species (henceforth beneficials) remains scarce. At present, the selection of pesticides compatible with IPM often considers a single (or a limited number of) widely distributed beneficial species, without considering undesired effects on co-occurring beneficials. In this study, we conducted standardised laboratory bioassays to assess the acute toxicity effects of 20 chemicals on 15 beneficial species at multiple exposure timepoints, with the specific aims to: (1) identify common and diverging patterns in acute toxicity responses of tested beneficials; (2) determine if the effect of pesticides on beetles, wasps and mites is consistent across species within these groups; and (3) assess the impact of mortality assessment timepoints on International Organisation for Biological Control (IOBC) toxicity classifications. Our work demonstrates that in most cases, chemical toxicities cannot be generalised across a range of beneficial insects and mites providing biological control, a finding that was found even when comparing impacts among closely related species of beetles, wasps and mites. Additionally, we show that toxicity impacts increase with exposure length, pointing to limitations of IOBC protocols. This work challenges the notion that chemical toxicities can be adequately tested on a limited number of 'representative' species; instead, it highlights the need for careful consideration and testing on a range of regionally and seasonally relevant beneficial species.


Asunto(s)
Agricultura , Plaguicidas , Animales , Plaguicidas/toxicidad , Agricultura/métodos , Ácaros/efectos de los fármacos , Pruebas de Toxicidad Aguda , Avispas/efectos de los fármacos , Control de Plagas/métodos , Escarabajos/efectos de los fármacos , Control Biológico de Vectores
4.
Science ; 383(6689): eadf2572, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38513026

RESUMEN

The environmental impacts of organic agriculture are only partially understood and whether such practices have spillover effects on pests or pest control activity in nearby fields remains unknown. Using about 14,000 field observations per year from 2013 to 2019 in Kern County, California, we postulate that organic crop producers benefit from surrounding organic fields decreasing overall pesticide use and, specifically, pesticides targeting insect pests. Conventional fields, by contrast, tend to increase pesticide use as the area of surrounding organic production increases. Our simulation suggests that spatially clustering organic cropland can entirely mitigate spillover effects that lead to an increase in net pesticide use.


Asunto(s)
Agricultura Orgánica , Control de Plagas , Plaguicidas , Ambiente , Plaguicidas/toxicidad , Simulación por Computador
5.
Chemosphere ; 355: 141784, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537714

RESUMEN

The improper use of synthetic pesticides has caused adverse effects on global ecosystems and human health. As a part of sustainable pest management strategy, natural predators, along with nano-pesticides, have made significant contributions to ecological agriculture. The cooperative application of both approaches may overcome their limitations, substantially reducing pesticide application while controlling insect pests efficiently. Herein, the current study introduced a cationic star polymer (SPc) to prepare two types of nano-pesticides, which were co-applied with predatory stinkbugs Picromerus lewisi to achieve perfect cooperative pest control. The SPc exhibited nearly no toxicity against predatory stinkbugs at the working concentration, but it led to the death of predatory stinkbugs at extremely high concentration with the lethal concentration 50 (LC50) value of 13.57 mg/mL through oral feeding method. RNA-seq analysis revealed that the oral feeding of SPc could induce obvious stress responses, leading to stronger phagocytosis, exocytosis, and energy synthesis to ultimately result in the death of predatory stinkbugs. Then, the broflanilide and chlorobenzuron were employed to prepare the self-assembled nano-pesticides via hydrogen bond and Van der Waals force, and the complexation with SPc broke the self-aggregated structures of pesticides and reduced their particle sizes down to nanoscale. The bioactivities of prepared nano-pesticides were significantly improved toward common cutworm Spodoptera litura with the corrected mortality increase by approximately 30%. Importantly, predatory stinkbugs exhibited a strong predation selectivity for alive common cutworms to reduce the exposure risk of nano-pesticides, and the nano-pesticides showed negligible toxicity against predators. Thus, the nano-pesticides and predatory stinkbugs could be applied simultaneously for efficient and sustainable pest management. The current study provides an excellent precedent for perfect cooperative pest control via nano-pesticide and natural predator.


Asunto(s)
Plaguicidas , Animales , Humanos , Plaguicidas/toxicidad , Ecosistema , Conducta Predatoria , Control Biológico de Vectores/métodos , Agricultura/métodos , Control de Plagas
7.
Commun Biol ; 7(1): 337, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499741

RESUMEN

Sustainable agriculture relies on implementing effective, eco-friendly crop protection strategies. However, the adoption of these green tactics by growers is limited by their high costs resulting from the insufficient integration of various components of Integrated Pest Management (IPM). In response, we propose a framework within IPM termed Multi-Dimensional Management of Multiple Pests (3MP). Within this framework, a spatial dimension considers the interactive effects of soil-crop-pest-natural enemy networks on pest prevalence, while a time dimension addresses pest interactions over the crop season. The 3MP framework aims to bolster the adoption of green IPM tactics, thereby extending environmental benefits beyond crop protection.


Asunto(s)
Agricultura , Control de Plagas , Control de Plagas/métodos , Agricultura/métodos , Protección de Cultivos
8.
Sci Total Environ ; 922: 171382, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38432369

RESUMEN

The present review addresses the significance of lowering pesticide residue levels in food items because of their harmful impacts on human health, wildlife populations, and the environment. It draws attention to the possible health risks-acute and chronic poisoning, cancer, unfavorable effects on reproduction, and harm to the brain or immunological systems-that come with pesticide exposure. Numerous traditional and cutting-edge methods, such as washing, blanching, peeling, thermal treatments, alkaline electrolyzed water washing, cold plasma, ultrasonic cleaning, ozone treatment, and enzymatic treatment, have been proposed to reduce pesticide residues in food products. It highlights the necessity of a paradigm change in crop protection and agri-food production on a global scale. It offers opportunities to guarantee food safety through the mitigation of pesticide residues in food. The review concludes that the first step in reducing worries about the negative effects of pesticides is to implement regulatory measures to regulate their use. In order to lower the exposure to dietary pesticides, the present review also emphasizes the significance of precision agricultural practices and integrated pest management techniques. The advanced approaches covered in this review present viable options along with traditional methods and possess the potential to lower pesticide residues in food items without sacrificing quality. It can be concluded from the present review that a paradigm shift towards sustainable agriculture and food production is essential to minimize pesticide residues in food, safeguarding human health, wildlife populations, and the environment. Furthermore, there is a need to refine the conventional methods of pesticide removal from food items along with the development of modern techniques.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Humanos , Residuos de Plaguicidas/análisis , Contaminación de Alimentos/prevención & control , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Inocuidad de los Alimentos , Control de Plagas
9.
Sci Rep ; 14(1): 6029, 2024 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-38472262

RESUMEN

Fall armyworm, Spodoptera frugiperda (FAW) is a cosmopolitan crop pest species that has recently become established in sub-Saharan Africa and Southeast Asia. Current FAW control is almost entirely dependent on synthetic pesticides. Biopesticides offer a more sustainable alternative but have limitations. For example, pyrethrum is an effective botanical insecticide with low mammalian toxicity but is highly UV labile, resulting in a rapid loss of efficacy in the field. Beauveria bassiana is an entomopathogenic fungus that is more persistent, but there is a time lag of several days before it causes insect mortality and leads to effective control. The combination of these biopesticides could mitigate their drawbacks for FAW control. Here we evaluated the efficacy of pyrethrum and B. bassiana as individual treatments and in combination against 3rd instar FAW. Four different combinations of these two biopesticides were tested, resulting in an antagonistic relationship at the lowest concentrations of B. bassiana and pyrethrum (1 × 104 conidia mL-1 with 25 ppm) and an additive effect for the other 3 combined treatments (1 × 104 conidia mL-1 with 100 ppm and 1 × 105 conidia mL-1 with 25 ppm and 100 ppm pyrethrum). Additionally, a delay in efficacy from B. bassiana was observed when combined with pyrethrum as well as a general inhibition of growth on agar plates. These results appear to show that this particular combination of biopesticides is not universally beneficial or detrimental to pest control strategies and is dependent on the doses of each biopesticide applied. However, the additive effect shown here at specific concentrations does indicate that combining biopesticides could help overcome the challenges of persistence seen in botanical pesticides and the slow establishment of EPF, with the potential to improve effectiveness of biopesticides for IPM.


Asunto(s)
Plaguicidas , Piretrinas , Animales , Agentes de Control Biológico , Larva , Control de Plagas , Spodoptera/fisiología
10.
Elife ; 132024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477562

RESUMEN

Over two decades ago, an intercropping strategy was developed that received critical acclaim for synergizing food security with ecosystem resilience in smallholder farming. The push-pull strategy reportedly suppresses lepidopteran pests in maize through a combination of a repellent intercrop (push), commonly Desmodium spp., and an attractive, border crop (pull). Key in the system is the intercrop's constitutive release of volatile terpenoids that repel herbivores. However, the earlier described volatile terpenoids were not detectable in the headspace of Desmodium, and only minimally upon herbivory. This was independent of soil type, microbiome composition, and whether collections were made in the laboratory or in the field. Furthermore, in oviposition choice tests in a wind tunnel, maize with or without an odor background of Desmodium was equally attractive for the invasive pest Spodoptera frugiperda. In search of an alternative mechanism, we found that neonate larvae strongly preferred Desmodium over maize. However, their development stagnated and no larva survived. In addition, older larvae were frequently seen impaled and immobilized by the dense network of silica-fortified, non-glandular trichomes. Thus, our data suggest that Desmodium may act through intercepting and decimating dispersing larval offspring rather than adult deterrence. As a hallmark of sustainable pest control, maize-Desmodium push-pull intercropping has inspired countless efforts to emulate stimulo-deterrent diversion in other cropping systems. However, detailed knowledge of the actual mechanisms is required to rationally improve the strategy, and translate the concept to other cropping systems.


Asunto(s)
Ecosistema , Control de Plagas , Animales , Agricultura , Larva , Spodoptera , Terpenos , Zea mays
11.
Sci Rep ; 14(1): 7118, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532112

RESUMEN

Invasive alien species (IAS) pose a severe threat to global agriculture, with their impact projected to escalate due to climate change and expanding international trade. The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), a native of the Americas, has rapidly spread across various continents, causing significant damage to several food crops, especially maize. Integrated pest management (IPM) programs are vital for sustainable FAW control, combining multiple strategies for sustainable results. Over three consecutive years, 2019-20, 2020-21 and 2021-22, the field demonstrations were conducted in semiarid regions of India, testing a four-component IPM approach viz., pheromone traps, microbial, botanicals and ETL based applications of insecticides against farmers' practices (sole insecticide application). IPM implementation led to substantial reductions in FAW infestation. Furthermore, egg mass and larvae infestations were significantly lower in IPM-adopted villages compared to conventional practices. Pheromone-based monitoring demonstrated a consistent reduction in adult moth populations. The lowest technology gap (10.42), extension gap (8.33) and technology index (12.25) was recorded during 2020-21. The adoption of IPM led to increased maize yields (17.49, 12.62 and 24.87% over control), higher net returns (919, 906.20 and 992.93 USD), and favourable benefit-cost ratios (2.74, 2.39 and 2.33) compared to conventional practices respectively during 2019-20, 2020-21 and 2021-22. The economic viability of IPM strategies was evident across three consecutive years, confirming their potential for sustainable FAW management in the semiarid region of India. These strategies hold promise for adoption in other parts of the world sharing similar climatic conditions.


Asunto(s)
Agricultores , Insecticidas , Animales , Humanos , Spodoptera , Zea mays , Comercio , Internacionalidad , Control de Plagas , India , Feromonas
12.
Int J Biol Macromol ; 263(Pt 1): 130607, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447848

RESUMEN

Bactrocera dorsalis is a notorious pest widely distributed across most Asian countries. With the rapid development of pesticide resistance, new pest control methods are urgently needed. RNAi-based sterile insect technique (SIT) is a species-specific pest management strategy for B. dorsalis control. It is of great significance to identify more target genes from B. dorsalis, and improve the RNAi efficiency. In this study, microinjection-based RNAi results showed that six 20E response genes were necessary for male fertility of B. dorsalis, of which E75 was identified as the key target according to the lowest egg-laying number and hatching rate after E75 knockdown. Three nanoparticles chitosan (CS), chitosan­sodium tripolyphosphate (CS-TPP), and star polycation (SPc) were used to encapsulate dsE75 expressed by HT115 strain. Properties analysis of nanoparticle-dsRNA complexes showed that both CS-TPP-dsRNA and SPc-dsRNA exhibited better properties (smaller size and polydispersity index) than CS-dsRNA. Moreover, oral administration of CS-TPP-dsE75 and SPc-dsE75 by males resulted in more abnormal testis and significantly lower fertility than feeding naked dsE75. Semi-field trials further confirmed that the number of hatched larvae was dramatically reduced in these two groups. Our study not only provides more valuable targets for RNAi-based SIT, but also promotes the application of environment-friendly management against B. dorsalis in the field.


Asunto(s)
Quitosano , Infertilidad , Nanopartículas , Tephritidae , Animales , Masculino , Interferencia de ARN , Ecdisona , Insectos , Control de Plagas
13.
Sci Rep ; 14(1): 6821, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514777

RESUMEN

Agricultural extension services have been successful in promoting knowledge sharing and innovation in agriculture. However, the adoption of new agricultural practices, particularly in integrated pest management, has been slow. Using a case study with a co-designed survey instrument, this research aimed to understand how growers in the Southwest Western Australian Grainbelt access information and resources to manage fungicide resistance. We found that the growers rely on a combination of paid agronomists, government or research institutes, local grower groups, and field days for fungicide resistance information. Growers seek information from trusted experts who can simplify complex research, value easy-to-understand communication and prefer resources tailored to their local context. Additionally, growers valued information regarding new fungicide developments and having access to rapid fungicide resistance diagnostic services. These findings highlight the importance of providing growers with effective agricultural extension services to manage the risk of fungicide resistance.


Asunto(s)
Fungicidas Industriales , Fungicidas Industriales/farmacología , Australia , Agricultura , Control de Plagas , Actitud
14.
Mol Biol Rep ; 51(1): 355, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38400844

RESUMEN

Nanoparticle-based delivery systems have emerged as powerful tools in the field of pest management, offering precise and effective means of delivering double-stranded RNA (dsRNA), a potent agent for pest control through RNA interference (RNAi). This comprehensive review aims to evaluate and compare various types of nanoparticles for their suitability in dsRNA delivery for pest management applications. The review begins by examining the unique properties and advantages of different nanoparticle materials, including clay, chitosan, liposomes, carbon, gold and silica. Each material's ability to protect dsRNA from degradation and its potential for targeted delivery to pests are assessed. Furthermore, this review delves into the surface modification strategies employed to enhance dsRNA delivery efficiency. Functionalization with oligonucleotides, lipids, polymers, proteins and peptides is discussed in detail, highlighting their role in improving stability, cellular uptake, and specificity of dsRNA delivery.This review also provides valuable guidance on choosing the most suitable nanoparticle-based system for delivering dsRNA effectively and sustainably in pest management. Moreover, it identifies existing knowledge gaps and proposes potential research directions aimed at enhancing pest control strategies through the utilization of nanoparticles and dsRNA.


Asunto(s)
Nanopartículas , ARN Bicatenario , Animales , Insectos/genética , Interferencia de ARN , Liposomas/metabolismo , Control de Plagas
15.
Chemosphere ; 352: 141530, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38401868

RESUMEN

In view of the ongoing climate change and the ever-growing world population, novel agricultural solutions are required to ensure sustainable food supply. Microbials, natural substances, semiochemicals and double stranded RNAs (dsRNAs) are all considered potential low risk pesticides. DsRNAs function at the molecular level, targeting specific regions of specific genes of specific organisms, provided that they share a minimal sequence complementarity of approximately 20 nucleotides. Thus, dsRNAs may offer a great alternative to conventional chemicals in environmentally friendly pest control strategies. Any low-risk pesticide needs to be efficient and exhibit low toxicological potential and low environmental persistence. Having said that, in the current review, the mode of dsRNA action is explored and the parameters that need to be taken into consideration for the development of efficient dsRNA-based pesticides are highlighted. Moreover, since dsRNAs mode of action differs from those of synthetic pesticides, custom-made risk assessment schemes may be required and thus, critical issues related to the risk assessment of dsRNA pesticides are discussed here.


Asunto(s)
Plaguicidas , Plaguicidas/toxicidad , Interferencia de ARN , ARN Bicatenario/genética , Control de Plagas , Medición de Riesgo
16.
J Econ Entomol ; 117(2): 601-608, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38402524

RESUMEN

The Professional Pest Management Industry (PPMI) dates back over a century in the United States. Stakeholder calls for economic studies of the PPMI include, in the 1980s, the National Research Council, although there has been little to no progress on that topic. US Census and Bureau of Labor Statistics data indicate that revenue and employment for the PPMI in Georgia increased 117% from 1997 to 2021. We determined the revenue, employment, and economic contributions for the PPMI in Georgia, United States, using 2 methodologies applied to IMPLAN: primary survey data in combination with an open records request and publicly available Federal Economic data. Estimates of average revenue for the Georgia PPMI in 2021 were $833-$988 million, using the survey/open records and publicly available data, respectively. We utilized an economic modeling program, IMPLAN, to estimate the economic contributions by the Georgia PPMI in 2021 to be between $1.7 and $2.0 billion, with 13,000-14,000 jobs for the 2 respective data sets. We describe the methods and provide tutorials for other states or national organizations to follow to generate justifiable, comparable economic information on the PPMI. In addition, we discuss the unique position of the PPMI as heavily regulated by State Departments of Agriculture to advocate for including the PPMI economic values when reporting agricultural economic contributions.


Asunto(s)
Agricultura , Empleo , Estados Unidos , Animales , Georgia , Control de Plagas
17.
PeerJ ; 12: e16859, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410805

RESUMEN

Background: The fall armyworm, Spodoptera frugiperda, is an agricultural pest of significant economic concern globally, known for its adaptability, pesticide resistance, and damage to key crops such as maize. Conventional chemical pesticides pose challenges, including the development of resistance and environmental pollution. The study aims to investigate an alternative solution: the application of soluble silicon (Si) sources to enhance plant resistance against the fall armyworm. Methods: Silicon dioxide (SiO2) and potassium silicate (K2SiO3) were applied to maize plants via foliar spray. Transcriptomic and biochemical analyses were performed to study the gene expression changes in the fall armyworm feeding on Si-treated maize. Results: Results indicated a significant impact on gene expression, with a large number of differentially expressed genes (DEGs) identified in both SiO2 and K2SiO3 treatments. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified critical DEGs involved in specific pathways, including amino acid, carbohydrate, lipid, energy, xenobiotics metabolisms, signal transduction, and posttranslational modification, significantly altered at both Si sources. Biochemical analyses further revealed that Si treatments inhibited several enzyme activities (glutamate dehydrogenase, trehalase, glucose-6-phosphate dehydrogenase, chitinase, juvenile hormone esterase, and cyclooxygenase while simultaneously inducing others (total protein, lipopolysaccharide, fatty acid synthase, ATPase, and cytochrome P450), thus suggesting a toxic effect on the fall armyworm. In conclusion, Si applications on maize influence the gene expression and biochemical activities of the fall armyworm, potentially offering a sustainable pest management strategy.


Asunto(s)
Dióxido de Silicio , Zea mays , Animales , Spodoptera/genética , Zea mays/genética , Dióxido de Silicio/metabolismo , Control de Plagas , Perfilación de la Expresión Génica/veterinaria
18.
Pest Manag Sci ; 80(6): 2796-2803, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38327120

RESUMEN

BACKGROUND: Practical resistance of Helicoverpa zea to Cry proteins has become widespread in the US, making Vip3Aa the only effective Bacillus thuringiensis (Bt) protein for controlling this pest. Understanding the genetic basis of Vip3Aa resistance in H. zea is essential in sustaining the long-term efficacy of Vip3Aa. The objectives of this study were to characterize the inheritance of Vip3Aa resistance in four distinct field-derived H. zea strains (M1-RR, AC4-RR, R2-RR and R15-RR), and to test for shared genetic basis among these strains and a previously characterized Texas resistant strain (LT#70-RR). RESULTS: Maternal effects and sex linkage were absent, and the effective dominance level (DML) was 0.0 across Vip3Aa39 concentrations ranging from 1.0 to 31.6 µg cm-2, in all H. zea resistant strains. Mendelian monogenic model tests indicated that Vip3Aa resistance in each of the four strains was controlled by a single gene. However, interstrain complementation tests indicated that three distinct genetic loci are involved in Vip3Aa resistance in the five resistant H. zea strains: one shared by M1-RR and LT#70-RR; another shared by R2-RR and R15-RR; and a distinct one for AC4-RR. CONCLUSION: Results of this study indicate that Vip3Aa resistance in all H. zea strains was controlled by a single, recessive and autosomal gene. However, there were three distinct genetic loci associated with Vip3Aa resistance in the five resistant H. zea strains. The information generated from this study is valuable for exploring mechanisms of Vip3Aa resistance, monitoring the evolution of Vip3Aa resistance, and devising effective strategies for managing Vip3Aa resistance in H. zea. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Proteínas Bacterianas , Resistencia a Medicamentos , Mariposas Nocturnas , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/genética , Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Resistencia a Medicamentos/genética , Control de Plagas/métodos , Dosificación Letal Mediana , Prueba de Complementación Genética , Genes Recesivos/genética , Animales
19.
Appl Microbiol Biotechnol ; 108(1): 181, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38285209

RESUMEN

Bacillus thuringiensis (Bt) produces crystals composed mainly of Cry pesticidal proteins with insecticidal activity against pests but are highly susceptible to degradation by abiotic factors. In this sense, encapsulation techniques are designed to improve their performance and lifetime. However, the effects of polymeric matrix encapsulation such as gum arabic and maltodextrin by spray-dryer in the mechanisms of action of Bt kurstaki and Bt aizawai are unknown. We analyzed crystal solubilization, protoxin activation, and receptor binding after microencapsulation and compared them with commercial non-encapsulated products. Microencapsulation did not alter protein crystal solubilization, providing 130 kDa (Cry1 protoxin) and 70 kDa (Cry2 protoxin). Activation with trypsin, chymotrypsin, and larval midgut juice was analyzed, showing that this step is highly efficient, and the protoxins were cleaved producing similar ~ 55 to 65 kDa activated proteins for both formulations. Binding assays with brush border membrane vesicles of Manduca sexta and Spodoptera frugiperda larvae provided a similar binding for both formulations. LC50 bioassays showed no significant differences between treatments but the microencapsulated treatment provided higher mortality against S. frugiperda when subjected to UV radiation. Microencapsulation did not affect the mechanism of action of Cry pesticidal proteins while enhancing protection against UV radiation. These data will contribute to the development of more efficient Bt biopesticide formulations. KEY POINTS: • Microencapsulation did not affect the mechanisms of action of Cry pesticidal proteins produced by Bt. • Microencapsulation provided protection against UV radiation for Bt-based biopesticides. • The study's findings can contribute to the development of more efficient Bt biopesticide formulations.


Asunto(s)
Bacillus thuringiensis , Plaguicidas , Polisacáridos , Animales , Plaguicidas/farmacología , Goma Arábiga , Agentes de Control Biológico , Larva , Control de Plagas
20.
Methods Mol Biol ; 2771: 73-81, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38285393

RESUMEN

Since the discovery of the RNA interference (RNAi) mechanism, it has been widely used in the fields of gene function, biomedicine, and crop pest control. In the direction of agricultural application, this technology is highly expected, especially in the field of pest control, which is called "the third revolution in the history of pesticides". Currently, RNA biopesticides are developing rapidly all over the world. A genetically modified product (MON87411) has been approved for marketing, and a large number of agricultural companies are developing products based on direct spraying RNA biopesticides and submitting them for regulatory approval. The biggest problem that has emerged for spray RNA biopesticides is the technology for large-scale and low-cost production of dsRNA. At present, the bacterial fermentation production technology can realize large-scale dsRNA production with a yield of 4.23~182 mg/L bacterial solution. This article describes the experimental protocol for dsRNA production technology based on bacterial fermentation.


Asunto(s)
Agentes de Control Biológico , ARN Bicatenario , Animales , Interferencia de ARN , ARN Bicatenario/genética , Análisis Costo-Beneficio , Bacterias , Insectos , Control de Plagas
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