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2.
Braz. j. biol ; 84: e251883, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1350313

RESUMO

Abstract The lower lignin content in plants species with energy potential results in easier cellulose breakdown, making glucose available for ethanol generation. However, higher lignin levels can increase resistance to insect attack. The objective of this work was to evaluate the susceptibility of a bmr-6 biomass sorghum (a mutant genotype with a lower concentration of lignin) to important pests of energy sorghum, Diatraea saccharalis and Spodoptera frugiperda. Experiments were performed in the laboratory and greenhouse to evaluate the development of these pests on the biomass sorghum bmr hybrids BR007, BR008, and TX635 and their respective conventional near-isogenic genotypes (without the bmr gene). The lignin content was higher in non-bmr hybrids, but the evaluated insect variables varied between treatments, not being consistent in just one hybrid or because it is bmr or not. The lowest survival of S. frugiperda was observed in the BR008 hybrid, both bmr and non-bmr. The S. frugiperda injury scores on plants in the greenhouse were high (>7) in all treatments. For D. saccharalis, there was no difference in larval survival in the laboratory, but in the greenhouse, the BR007 hybrid, both bmr and non-bmr, provided greater survival. Due the need to diversify the energy matrix and the fact that greater susceptibility of the bmr hybrids to either pests was not found in this study, these results hold promise for cultivation of these biomass sorghum hybrids for the production of biofuels.


Resumo O menor teor de lignina em espécies de plantas com potencial energético resulta na maior facilidade de quebra da celulose, disponibilizando glicose para geração de etanol. Porém, maiores teores de lignina representa um fator de resistência ao ataque de insetos. O objetivo deste trabalho foi avaliar como importantes pragas do sorgo energia, Diatraea saccharalis e Spodoptera frugiperda, se comportam quanto à alimentação e desempenho em sorgo bmr-6, um genótipo mutante com menor concentração de lignina. Foram realizados experimentos em laboratório e casa de vegetação, avaliando o desenvolvimento destas pragas nos híbridos de sorgo biomassa bmr 007, 008, TX635 e seus respectivos genótipos isogênicos convencionais (sem o gene bmr). O teor de lignina foi maior nos híbridos não bmr, mas nos parâmetros avaliados nos insetos, houve variação entre os tratamentos, não sendo consistente em apenas um híbrido e nem por ser ou não bmr. A menor sobrevivência de S. frugiperda foi verificada no híbrido BR008 tanto bmr quanto não bmr. As notas de injúria por S. frugiperda no sorgo em casa de vegetação foram altas (>7) em todos os tratamentos. Para D. saccharalis, não houve diferença significativa para a sobrevivência larval em laboratório, mas em casa de vegetação o híbrido BR007 tanto bmr quanto não bmr proporcionaram maior sobrevivência. Diante da necessidade de diversificar a matriz energética e o fato de que não foi comprovada neste estudo maior suscetibilidade dos híbridos bmr a ambas as pragas, estes resultados são promissores para o cultivo desses híbridos de sorgo biomassa para produção de biocombustíveis.


Assuntos
Animais , Saccharum/genética , Sorghum/genética , Mariposas , Spodoptera , Larva
3.
Braz. j. biol ; 84: e254479, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1355910

RESUMO

Abstract Earias vittellaFabricius, 1794 (Noctuidae: Lepidoptera) is deliberated to be one of the most destructive pests of cotton and okra vegetation in the world including Asia. The pest has established resistance to various synthetic insecticides. The use of bio-pesticide is one of the unconventional approaches to develop a vigorous ecosystem without harming non- target pests and beneficial natural insect fauna. In the present study, the toxicity levels of Citrullus colocynthis seed extract have been evaluated against the populations of E. vittellaunder standardized laboratory conditions. The toxic effects of C. colocynthis on development periods, protein contents and esterase activity of the life stages of E. vittella were also evaluated. The toxicity levels of methanol, ethanol, hexane, water and profenofos were evaluated on the 1st instar larvae of E. vittella. LC30 and LC80 concentrations exhibited the effectiveness of methanol-based C. colocynthis seed extract against 1st instar larvae of E. vitella. The enhanced larval and pupal periods were revealed in treated samples during the comparison with untreated samples. The intrinsic rate of increase, net reproductive rate in the LC30 and LC80 concentrations exposed larvae remained less than the control treatment. Fecundity, the esterase activity and protein contents were declined in LC30 and LC80 treated samples as compared to the control. The present findings suggest that C. colosynthis extracts based botanical insecticides are beneficial, ecosystem sustainable and can be integrated with insect management programs from environment safety perspective.


Resumo Earias vittella Fabricius, 1794 (Noctuidae: Lepidoptera) é considerada uma das pragas mais destrutivas de algodão e quiabo no mundo, incluindo a Ásia. Essa praga estabeleceu resistência a vários inseticidas sintéticos. O uso de biopesticidas é uma das abordagens não convencionais para desenvolver um ecossistema saudável sem prejudicar as pragas não alvo e a fauna natural benéfica de insetos. No presente estudo, os níveis de toxicidade do extrato de semente de Citrullus colocynthis foram avaliados nas populações de E. vittella em condições de laboratório padronizadas. Os efeitos tóxicos de C. colocynthis nos períodos de desenvolvimento, conteúdo de proteína e atividade esterase das fases de vida de E. vittella também foram avaliados. Os níveis de toxicidade de metanol, etanol, hexano, água e profenofós foram avaliados em larvas de 1º instar de E. vittella. As concentrações de LC30 e LC80 apresentaram eficácia do extrato de sementes de C. colocynthis à base de metanol contra larvas de 1º instar de E. vittella. Os períodos larval e pupal aumentados foram revelados nas amostras tratadas durante a comparação com as amostras não tratadas. A taxa intrínseca de aumento e a taxa reprodutiva líquida nas concentrações de larvas expostas LC30 e LC80 permaneceram menores do que o tratamento controle. A fecundidade, a atividade da esterase e o conteúdo de proteína diminuíram nas amostras tratadas com LC30 e LC80 em comparação com o controle. As presentes descobertas sugerem que os extratos de C. colocynthis à base de inseticidas botânicos são benéficos, sustentáveis ​​para o ecossistema e podem ser integrados com programas de manejo de insetos do ponto de vista da segurança ambiental.


Assuntos
Animais , Citrullus colocynthis , Inseticidas , Mariposas , Extratos Vegetais/farmacologia , Ecossistema , Larva
4.
Braz. j. biol ; 83: e245273, 2023. tab
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339412

RESUMO

Abstract The possible interference of resistant pest's populations to insecticides in natural enemies in the action thas not been clarified yet. Thus, this study aimed to evaluate Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) performance on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) eggs with resistance frequency to the Metaflumizone over six generations of product exposure. Egg cards (2.0 x 7.0 cm) containing eggs from two populations of S. frugiperda, (resistant to Metaflumizone and the other susceptible), were exposed to T. pretiosum females for 24 hours in free-choice and no-choice testing in three generations (G1, G4, and G6). A completely randomized experimental design was used with 25 replications, each consisting of an egg card (experimental unit) containing 20 eggs. The parameters evaluated were: parasitism (%), emergence (%), sex ratio, number of emerged parasitoids per egg and males/females longevity. ANOVA and Tukey test (P≤ 0.05) were applied on the results. Results showed a reduction in parasitism [41.0% (G1) and 28.4% (G4)], egg emergence (17.5%) and parasitoids/egg [16.2 (G4) and 17.2 (G6)] in eggs originating from the population with resistance frequency. Females emerging from G6 populations eggs without exposure to Metaflumizone had greater longevity (3.5 days more) than the resistant population. The sex ratio and male longevity were not affected. The results indicate a reduction in T. pretiosum activity if S. frugiperda populations have some frequency of resistance to Metaflumizone.


Resumo A possível interferência de populações de pragas resistentes na ação de inimigos naturais ainda não foi esclarecida. Assim, este trabalho teve como objetivo avaliar o desempenho de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em ovos de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) com frequência de resistência à Metaflumizona ao longo de seis gerações de exposição ao produto. Cartelas (2,0 x 7,0 cm) com ovos de duas populações de S. frugiperda, (resistente à Metaflumizona e outra suscetível), foram expostas às fêmeas de T. pretiosum por 24 horas em condições de livre escolha e sem chance de escolha por três gerações (G1, G4 e G6). O delineamento experimental foi inteiramente casualizado com 25 repetições, sendo cada repetição composta por uma cartela (unidade experimental) contendo 20 ovos. Os parâmetros avaliados foram: parasitismo (%), emergência (%), razão sexual, número de parasitoides emergidos por ovo e longevidade de machos e fêmeas. ANOVA e teste de Tukey (P≤ 0,05) foram aplicados aos dados coletados. Os resultados mostraram redução do parasitismo [41,0% (G1) e 28,4% (G4)], emergência de ovos (17,5%) e parasitoides/ovo [16,2 (G4) e 17,2 (G6)] em ovos oriundos da população com frequência de resistência. As fêmeas emergidas de ovos da população G6 sem exposição à Metaflumizona, tiveram maior longevidade (3,5 dias a mais) do que a população exposta ao inseticida. A razão sexual e a longevidade de machos não foram afetadas. Os resultados indicam uma redução na atividade de T. pretiosum se as populações de S. frugiperda apresentarem alguma frequência de resistência à Metaflumizona.


Assuntos
Animais , Masculino , Feminino , Vespas , Himenópteros , Mariposas , Semicarbazonas , Razão de Masculinidade , Spodoptera
5.
Braz. j. biol ; 83: e246436, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339391

RESUMO

Abstract Application of different fertilizers to check the efficiency of expression of Bt (Bacillus thuringiensis) gene in one of the leading commercialized crops (cotton) against Lepidopteran species is of great concern. The expression of Cry protein level can be controlled by the improvement of nutrients levels. Therefore, the myth of response of Cry toxin to different combinations of NP fertilizers was explored in three Bt cotton cultivars. Combinations include three levels of nitrogen and three levels of phosphorus fertilizers. Immunostrips and Cry gene(s) specific primer based PCR (Polymerase Chain Reaction) analysis were used for the presence of Bt gene that unveiled the presence of Cry1Ac gene only. Further, the ELISA (enzyme-linked immunosorbent assay) kit was used to quantify the expression of Cry1Ac protein. Under various NP fertilizers rates, the level of toxin protein exhibited highly significant differences. The highest toxin level mean was found to be 2.3740 and 2.1732 µg/g under the treatment of N150P75 kg ha-1 combination while the lowest toxin level mean was found to be 0.9158 and 0.7641 µg/g at the N50P25 kg ha-1 level at 80 and 120 DAS (Days After Sowing), respectively. It was concluded from the research that the usage of NP fertilizers has a positive relation with the expression of Cry1Ac toxin in Bt cotton. We recommend using the N150P50 kg ha-1 level as the most economical and practicable fertilizer instead of the standard dose N100P50 kg ha-1 to get the desired level of Cry1Ac level for long lasting plant resistance (<1.5). The revised dose of fertilizer may help farmers to avoid the cross-resistance development in contradiction of insect pests.


Resumo A aplicação de diferentes fertilizantes para verificar a eficiência da expressão do gene Bt (Bacillus thuringiensis) em uma das principais culturas comercializadas (algodão) contra espécies de lepidópteros é uma grande preocupação. A expressão do nível de proteína Cry pode ser controlada pela melhoria dos níveis de nutrientes. Portanto, o mito da resposta da toxina Cry a diferentes combinações de fertilizantes NP foi explorado em três cultivares de algodão Bt. As combinações incluem três níveis de nitrogênio e três níveis de fertilizantes de fósforo. A análise de PCR (reação em cadeia da polimerase) específica para o gene (s) Immunostrips e Cry (s) foi usada para a presença do gene Bt que revelou a presença do gene Cry1Ac apenas. Além disso, o kit ELISA (ensaio de imunoabsorção enzimática) foi usado para quantificar a expressão da proteína Cry1Ac. Sob várias taxas de fertilizantes NP, o nível de proteína de toxina exibiu diferenças altamente significativas. A média do nível mais alto de toxina foi de 2,3740 e 2,1732 µg / g sob o tratamento da combinação N150P75 kg ha-1, enquanto a média do nível mais baixo de toxina foi de 0,9158 e 0,7641 µg / g no nível de N50P25 kg ha-1 em 80 e 120 DAS (dias após a semeadura), respectivamente. Concluiu-se com a pesquisa que o uso de fertilizantes NP tem relação positiva com a expressão da toxina Cry1Ac no algodão Bt. Recomendamos o uso do nível de N150P50 kg ha-1 como o fertilizante mais econômico e praticável em vez da dose padrão N100P50 kg ha-1 para obter o nível desejado de nível de Cry1Ac para resistência de planta de longa duração (<1,5). A dose revisada de fertilizante pode ajudar os agricultores a evitar o desenvolvimento de resistência cruzada em contradição com as pragas de insetos.


Assuntos
Animais , Proteínas Hemolisinas/genética , Mariposas , Fósforo , Proteínas de Bactérias/genética , Resistência a Inseticidas , Plantas Geneticamente Modificadas/genética , Endotoxinas/genética , Fertilizantes , Toxinas de Bacillus thuringiensis , Larva , Nitrogênio
6.
In Vitro Cell Dev Biol Anim ; 58(1): 14-20, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35075604

RESUMO

Extensive usage of synthetic chemical pesticides has collateral effects in harming human and animal health and the environment and promoting the development of resistance in pests. The potential of plant compounds as bio insecticides has been described as a promising field of agricultural development. The present study involved the use of Artemisia annua essential oils to evaluate their cytotoxic activities against an established cell line of lesser mulberry pyralid. Five types of hemocytes were recognized (prohaemocytes, plasmatocytes, granulocytes, oenocytoids, and spherulocytes) in the primary cultures maintained in Ex-Cell media with 10% fetal bovine serum (FBS). Artemisia annua essential oils produced noticeable cytotoxicity against the insect cell lines. Applied at a concentration 500 ppm, oils extracted from the vegetative or flowering stages of A. annua produced 71% and 80% cell death, respectively. Nanoemulsions of EOs from the vegetative or flowering stages of A. annua killed 67 and 60% of the cells, respectively. This study has clearly shown significant bioactivities of A. annua secondary metabolites to insect cell lines.


Assuntos
Artemisia annua , Asteraceae , Mariposas , Óleos Voláteis , Animais , Artemisia annua/química , Linhagem Celular , Hemócitos , Óleos Voláteis/química , Óleos Voláteis/farmacologia
7.
J Insect Sci ; 22(3)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512683

RESUMO

Helicoverpa armigera (Hübner) (Noctuidae: Lepidopetra) is a polyphagous pest of major crops grown in India. To prevent the damage caused by H. armigera farmers rely heavily on insecticides of diverse groups on a regular basis which is not a benign practice, environmentally and economically. To provide more efficient and accurate information on timely application of insecticides, this research was aimed to develop a forecast model to predict population dynamics of pod borer using Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Networks (ANN). The data used in this study were collected from the randomly installed sex pheromone traps at International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Hyderabad. Several ARIMA (p, d, q) (P, D, Q) and ANN models were developed using the historical trap catch data. ARIMA model (1,0,1), (1,0,2) with minimal BIC, RMSE, MAPE, MAE, and MASE values and higher R2 value (0.53) was selected as the best ARIMA fit model, and neural network (7-30-1) was found to be the best fit to predict the catches of male moths of pod borer from September 2021 to August 2023. A comparative analysis performed between the ARIMA and ANN, shows that the ANN based on feed forward neural networks is best suited for effective pest prediction. With the developed ARIMA model, it would be easier to predict H. armigera adult population dynamics round the year and timely intervention of control measures can be followed by appropriate decision-making schedule for insecticide application.


Assuntos
Inseticidas , Mariposas , Animais , Previsões , Incidência , Masculino , Redes Neurais de Computação
8.
PLoS One ; 17(5): e0268236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35533149

RESUMO

Large natural disturbances such as insect outbreaks and fire are important processes for biodiversity in forest landscapes. However, few methods exist for incorporating natural disturbances into conservation planning. Intact forest landscapes, such as in the North American boreal forest, can produce large natural disturbance footprints. They also have the potential to support large reserves but size estimates based on natural disturbance are needed to guide reserve design. Historical fire data have been used to estimate minimum dynamic reserves, reserve size estimates based on maintaining natural disturbance dynamics and ensuring resilience to large natural disturbance events. While this has been a significant step towards incorporating natural disturbance into reserve design, managers currently lack guidance on how to apply these concepts in areas where fire is not the dominant natural disturbance. We generalize the minimum dynamic reserve framework to accommodate insect outbreaks and demonstrate the framework in a case study for eastern spruce budworm (Choristoneura fumiferana) in the Canadian boreal forest. Our methods use geospatial analysis to identify minimum dynamic reserves based on a set of spatially explicit initial conditions, and simulation models to test for the maintenance of a set of dynamic conditions over time. We found considerable variability in minimum dynamic reserve size depending on the size of historic budworm disturbance events and the spatial patterns of disturbance-prone vegetation types. The minimum dynamic reserve framework provides an approach for incorporating wide-ranging natural disturbances into biodiversity conservation plans for both pro-active planning in intact landscapes, and reactive planning in more developed regions.


Assuntos
Incêndios , Mariposas , Animais , Canadá , Conservação dos Recursos Naturais/métodos , Ecossistema , Florestas , Taiga
9.
Viruses ; 14(4)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35458418

RESUMO

Helicoverpa armigera single nucleopolyhedrovirus (HearSNPV) is a virulent pathogen of lepidopterans in the genera Heliothis and Helicoverpa, whereas Helicoverpa armigera multiple nucleopolyhedrovirus (HearSNPV) is a different virus species with a broader host range. This study aimed to examine the consequences of coocclusion of HearSNPV and HearMNPV on the pathogenicity, stability and host range of mixed-virus occlusion bodies (OBs). HearSNPV OBs were approximately 6-fold more pathogenic than HearMNPV OBs, showed faster killing by approximately 13 h, and were approximately 45% more productive in terms of OB production per larva. For coocclusion, H. armigera larvae were first inoculated with HearMNPV OBs and subsequently inoculated with HearSNPV OBs at intervals of 0-72 h after the initial inoculation. When the interval between inoculations was 12-24 h, OBs collected from virus-killed insects were found to comprise 41-57% of HearSNPV genomes, but the prevalence of HearSNPV genomes was greatly reduced (3-4%) at later time points. Quantitative PCR (qPCR) analysis revealed the presence of HearSNPV genomes in a small fraction of multinucleocapsid ODVs representing 0.47-0.88% of the genomes quantified in ODV samples, indicating that both viruses had replicated in coinfected host cells. End-point dilution assays on ODVs from cooccluded mixed-virus OBs confirmed the presence of both viruses in 41.9-55.6% of wells that were predicted to have been infected by a single ODV. A control experiment indicated that this result was unlikely to be due to the adhesion of HearSNPV ODVs to HearMNPV ODVs or accidental contamination during ODV band extraction. Therefore, the disparity between the qPCR and end-point dilution estimates of the prevalence of mixed-virus ODVs likely reflected virus-specific differences in replication efficiency in cell culture and the higher infectivity of pseudotyped ODVs that were produced in coinfected parental cells. Bioassays on H. armigera, Spodoptera frugiperda and Mamestra brassicae larvae revealed that mixed-virus OBs were capable of infecting heterologous hosts, but relative potency values largely reflected the proportion of HearMNPV present in each mixed-virus preparation. The cooccluded mixtures were unstable in serial passage; HearSNPV rapidly dominated during passage in H. armigera whereas HearMNPV rapidly dominated during passage in the heterologous hosts. We conclude that mixed-virus coocclusion technology may be useful for producing precise mixtures of viruses with host range properties suitable for the control of complexes of lepidopteran pests in particular crops, although this requires validation by field testing.


Assuntos
Mariposas , Nucleopoliedrovírus , Animais , Larva , Virulência
10.
Zootaxa ; 5124(3): 359-374, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35391118

RESUMO

A taxonomic review of the Afrotropical Thyatirinae is given and a new genus reminiscent of the Oriental Horipsestis Matsumura, 1933 is established for a new East African species: Watsonopsestis smithi gen. n., sp. n. Based on the analysis of the genital morphology, Aethiopsestis austrina nebulosa Watson, 1965, is raised to species rank: A. nebulosa Watson, 1965 stat. n., and the tribe Aethiopsestini is downgraded to subtribe rank: Aethiopsestina Watson, 1965 stat. n. The female adult and genitalia of Aethiopsestis mufindiae Watson, 1965 are illustrated and the latter is described for the first time. New locality records of Marplena designina Lane, 1973, Aethiopsestis nebulosa and A. mufindiae are reported. A distribution map of all known Afrotropical Thyatirinae is provided. The holotypes and additional specimens of all species together with their genitalia are illustrated in 18 colour and 16 black and white figures.


Assuntos
Lepidópteros , Mariposas , Distribuição Animal , Animais , Feminino , Genitália
11.
Zootaxa ; 5115(1): 63-78, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35391380

RESUMO

The footman moth genus Gracililema Krger, 2015 is reviewed and three new species are described: Gracililema bettoni sp. n. (Kenya and Ethiopia), G. lydiae sp. n. (northern Mozambique, Zimbabwe, Zambia, Tanzania, Kenya and Ethiopia) and G. smithi sp. n. (southern Mozambique and eastern South Africa). Adults, except the unknown male of G. proleucodes (Kiriakoff, 1958), together with male and female genitalia of all Gracililema species are illustrated.


Assuntos
Mariposas , Animais , Feminino , Masculino
12.
Zootaxa ; 5094(1): 103-128, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35391460

RESUMO

In this study, two genera of Afrotropical Sesiidae, Tipulamima Holland, 1893 and Macrotarsipodes Le Cerf, 1916 stat. rev., are redefined and redescribed, the latter being resurrected from synonymy with the former as a valid genus. Both genera are confirmed to belong to the tribe Synanthedonini. The genera closest to Tipulamima are unknown. Macrotarsipodes is related to Macrotarsipus Hampson, [1893] from Southeast Asia and Lepidopoda Hampson, 1900 from Africa and Southeast Asia. The latter genus as well as Pedalonina are transferred to Synanthedonini. Uranothyris Meyrick, 1933 syn. nov. is regarded as a subjective junior synonym of Tipulamima. Checklists of the species assigned to Tipulamima and Macrotarsipodes are provided. One new species, Tipulamima hesperia sp. nov., from Guinea and Ghana and the previously unknown male of T. pterotarsa (Meyrick, 1933) comb. nov. (Uranothyris) are described and depicted. The following new combinations are introduced: Macrotarsipodes leptosceles (Bradley, 1968) comb. nov. (Synanthedon), M. pedunculata (Hampson, 1910) comb. nov. (Ichneumenoptera), M. sexualis (Hampson, 1910) comb. nov. (Macrotarsipus), M. tricinctus Le Cerf, 1916 comb. rev., Synanthedon malimba (Beutenmller, 1899) comb. nov. (Sesia), Malgassesia ivondro (Viette, 1955) comb. nov. (Tipulamima), M. opalimargo (Le Cerf, 1913) comb. nov. (Sesia), Lepidopoda aericincta (Meyrick, 1928) comb. nov. (Aegeria), L. cyanospira (Meyrick, 1928) comb. nov. (Aegeria), L. dasysceles (Bradley, 1968) comb. nov. (Synanthedon), L. erythromma (Hampson, 1919) comb. nov. (Synanthedon), L. festiva (Beutenmller, 1899) comb. nov. (Sesia), L. flavipalpis Hampson, 1910 comb. rev., L. nuba (Beutenmller, 1899) comb. nov. (Sesia), L. rubripicta (Hampson, 1919) comb. nov. (Synanthedon), L. waterloti (Le Cerf, 1913) comb. nov. stat. nov. (Macrotarsipodes), Episannina sylphina (Hampson, 1919) comb. nov. (Lepidopoda) (Synanthedonini), Chamanthedon auronitens (Le Cerf, 1913) comb. nov. (Sesia), Pyranthrene hypocalla (Le Cerf, 1937) comb. nov. (Tipulamima), P. nigriceps (Hampson, 1919) comb. nov. (Tipulamima) (Osminiini). Junior subjective synonyms are: Aegeria rubripalpis Meyrick, 1932 syn. nov. of L. rubripicta, Aegeria mercatrix Meyrick, 1931 syn. nov. of L. aericincta and Aegeria pyrostoma Meyrick, 1927 syn. rev. of L. erythromma. Lectotypes of Tipulamima haugi (Le Cerf, 1917), T. flammipes (Hampson, 1910) and Macrotarsipodes sexualis comb. nov. are designated. Clerodendrum paniculatum L. (Lamiaceae) is reported as a host plant of Tipulamima for the first time. The larvae of three species of Macrotarsipodes and several species of Lepidopoda are known to be pests of Ipomoea batatas (L.) Lam. (Convolvulaceae).


Assuntos
Mariposas , Odonatos , Animais , Larva , Masculino , Países Baixos
13.
J Agric Food Chem ; 70(17): 5319-5329, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35441514

RESUMO

To discover new potential botanical insecticides from plant secondary metabolites, a series of new honokiol-type monoester/diester derivatives containing the core scaffold of benzodihydrofuran were synthesized by structural modification of honokiol. Against Mythimna separata Walker, 2-hydroxymethy-5-(2'-(para-chlorobenzoyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (5) and 2-(2″-chloropyridin-5″-ylcarbonyloxy)methylene-5-(2'-(2″-chloropyridin-5″-ylcarbonyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (37) displayed >2.1-fold promising insecticidal activity of the precursor honokiol. Against Aphis citricola Van der Goot, 2-hydroxymethy-5-(2'-(tridecylcarbonyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (21) (LD50: 0.049 µg/nymph) and 2-(para-fluorobenzylcarbonyloxy)methylene-5-(2'-(para-fluorobenzylcarbonyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (31) (LD50: 0.040 µg/nymph) showed 3.5- and 4.3-folds potent aphicidal activity of honokiol (LD50: 0.171 µg/nymph), respectively. Interestingly, 2-(tridecylcarbonyloxy)methylene-5-(2'-(tridecylcarbonyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (46) (LC50: 0.186 mg/mL) and 2-(dodecylcarbonyloxy)methylene-5-(2'-(dodecylcarbonyloxy)-5'-(1″,2″-epoxypropanyl))phenyl-2,3-dihydrobenzofuran (53) (LC50: 0.159 mg/mL: >6.4-fold of honokiol (LC50: 1.024 mg/mL)) exhibited promising acaricidal activity and control efficiency against Tetranychus cinnabarinus Boisduval. Structure-activity relationships indicated that a specific length of the aliphatic chain is necessary for the agricultural activities of honokiol monoester/diester derivatives, especially for the acaricidal activity of diester derivatives.


Assuntos
Acaricidas , Produtos Biológicos , Inseticidas , Lignanas , Mariposas , Acaricidas/farmacologia , Animais , Produtos Biológicos/química , Compostos de Bifenilo , Proteção de Cultivos , Inseticidas/química , Inseticidas/farmacologia , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade
14.
Appl Microbiol Biotechnol ; 106(8): 3051-3067, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35441877

RESUMO

The most crucial yield constraint of pigeon pea is susceptibility to the pod borer Helicoverpa armigera, which causes extensive damage and severe economic losses every year. The Agrobacterium-mediated plumular meristem transformation technique was applied for the development of cry1Ac transgenic pigeon pea. Bioactivity of the cry1Ac gene was compared based on integration and expression driven by two promoters, the constitutive CaMV35S promoter and the green-tissue-specific ats1A promoter, in those transgenic events. The transgenic events also contained the selectable marker gene nptII flanked by loxP sites. Independent transgenic events expressing the Cre recombinase gene along with a linked bar selection marker were also developed. Integration and expression patterns of both cry1Ac and cre were confirmed through Southern and western blot analysis of T1 events. The constitutive expression of the Cry1Ac protein was found to be more effective for conferring resistant activity against H. armigera larvae in comparison to green-tissue-specific expression. Constitutively expressing Cry1Ac T1 events were crossed with Cre recombinase expressing T1 events. The crossing-based Cre/lox-mediated marker gene elimination strategy was demonstrated to generate nptII-free Cry1Ac-expressing T2 events. These events were subsequently analyzed in the T3 generation for the segregation of cre and bar genes. Five Cry1Ac-expressing T3 transgenic pigeon pea events were devoid of the nptII marker as well as cre-bar genes. H. armigera larval mortality in those marker-free T3 events was found to be 80-100%. The development of such nptII selectable marker-free Cry1Ac-expressing pigeon pea transgenics for the first time would greatly support the sustainable biotechnological breeding program for pod borer resistance in pigeon pea. KEY POINTS: • Constitutive expression of Cry1Ac conferred complete resistance against Helicoverpa armigera • Green-tissue-specific expression of Cry1Ac conferred partial pest resistance • Cre/lox-mediated nptII elimination was successful in constitutively expressing Cry1Ac transgenic pigeon pea events.


Assuntos
Cajanus , Mariposas , Agrobacterium/genética , Animais , Cajanus/genética , Cajanus/metabolismo , Mariposas/genética , Plantas Geneticamente Modificadas/genética , Tecnologia
15.
Bioorg Med Chem ; 62: 116727, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35366437

RESUMO

In the search for novel more effective insecticides, natural products could be used as ideal template compounds due to their good environmental compatibility, various bioactivities, unique scaffolds and mode of action. We have found that natural product evodiamine, the main active component from the fruits of Evodia rutaecarpa (Juss.) Benth, displayed obvious insecticidal activities against lepidoptera pests. To continue our research, a series of evodiamine derivatives 3a-3aa were rationally designed and synthesized. The larvicidal activities results indicated that most of target compounds displayed better efficacy than evodiamine, matrine, and rotenone against Mythimna separata, Plutella xylostella and Helicoverpa armigera, among which 3z exhibited excellent larvicidal activities (65% at 2.5 mg/L against M. separata, 75% at 1.0 mg/L against P. xylostella, and 85% 10 mg/L against H. armigera, respectively), much better than evodiamine (0%), matrine (0%), and rotenone (0%). The preliminary structure activity relationships demonstrated that the fluorine atom at the E ring of evodiamine had a positive influence on the larvicidal activity. The calcium imaging experiment studies indicated that 3z could act on the ryanodine receptor (RyR) of M. separata and was an effective calcium activator for RyR.


Assuntos
Inseticidas , Mariposas , Animais , Cálcio , Inseticidas/química , Inseticidas/farmacologia , Larva , Estrutura Molecular , Mariposas/metabolismo , Quinazolinas , Rotenona , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
16.
PLoS One ; 17(4): e0266100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35417496

RESUMO

The Psyra Walker, 1860, is a typical Sino-Himalayan genus of the subfamily Ennominae, currently known by 18 species/4 subspecies globally and 9 species from India. This study aims to revise the taxonomy and ecology of Indian Psyra by providing a morphology-based diagnostic key, highlighting their altitudinal, habitat and seasonal preferences, and modelling their distribution based on current and future climatic scenarios. Here, we describe a new species, P. variabilis sp. nov. and document 4 species and 1 subspecies as new to India, viz. P. gracilis, P. szetschwana, P. dsagara, P. falcipennis and P. debilis debilis, thus updating the global species count to 19 with 14 species/1 subspecies from India. We also submitted partial mitochondrial COI sequences of P. crypta, P. similaria, P. spurcataria and P. gracilis as novel to the global genetic database and calculated the overall genetic divergence was 5.17% within the genus, suggesting strong monophyly. Being a typical montane genus, most of the species of Psyra were active within 2000-2280 m altitude, 10.55-15.7°C annual mean temperature, 1200-2300 mm annual precipitation and 168-179 NDVI. Psyra species were predominant in wet temperate, mixed coniferous and moist temperate deciduous forests, their abundance and richness being at peak during post-monsoon months of October-November. The major bioclimatic variables influencing the overall distribution of the genus were mean temperature of warmest quarter, temperature seasonality and precipitation of coldest/driest quarter. While two of the modelled species were predicted to lose area occupancy under future climatic scenarios, the narrow-specialist, Trans-Himalayan species P. debilis debilis was projected to gain up to 75% additional area in the years 2041-60. The results of this study will be helpful to identify sites with maximum area loss projection in ecologically fragile Indian Himalaya and initiating conservation management for such climatically vulnerable insect species groups.


Assuntos
Ecossistema , Mariposas , Animais , Ecologia , Florestas , Temperatura
17.
J Vis Exp ; (181)2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35404362

RESUMO

Tortricidae (Lepidoptera), commonly known as tortrix or leafroller moths, comprises many agricultural and forestry pests, which cause serious agricultural losses. To understand the biology of such pest moths, fundamental techniques have been in high demand. Here, methods for mass-rearing, observations, and molecular studies are developed using two tea tortrix, Homona magnanima and Adoxophyes honmai (Lepidoptera: Tortricidae). Insects were mass-reared with sliced artificial diet and maintained by inbreeding for over 100 generations by considering their biological characteristics. Insects have various sex dimorphisms; hence it is difficult to distinguish the sex during the developing stages, which have prevented subsequent assays. The present work highlighted that the sex of tortricids larvae could be determined by observing testes or lactic-acetic orcein staining to visualize the female-specific W chromosome. Moreover, using the sex determination methods, the present study enabled nucleic acid extractions from sex determined embryos and application toward high throughput sequencing. These tips are applicable for other pest insects and will facilitate further morphological and genetic studies.


Assuntos
Mariposas , Animais , Feminino , Larva/genética , Mariposas/genética
18.
Virus Genes ; 58(3): 227-237, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35380378

RESUMO

The complete genome sequence was determined for an apparent alphabaculovirus isolated from larval cadavers of the brown tussock moth, Olene mendosa Hübner, collected during an epizootic in Coimbatore, India. The genome was determined to be a circular 142,291 bp molecule, and 147 ORFs and nine homologous regions were annotated for the sequence. Analysis of the sequence confirmed that this virus, Olene mendosa nucleopolyhedrovirus (OlmeNPV), was a member of genus Alphabaculovirus in family Baculoviridae. Phylogenies inferred from nucleotide and amino acid alignments indicated that OlmeNPV was part of a group of viruses that infect moths of genus Lymantria, suggesting that OlmeNPV may have shifted hosts from a Lymantria species to an ancestral Olene species at some point during its evolutionary history. OlmeNPV was most closely related to Lymantria xylina multiple nucleopolyhedrovirus isolate 5 (LyxyMNPV-5). The genomes of OlmeNPV and LyxyMNPV-5 were distinguished not only by differences in ORF content, but by a 27 kbp region of the genome that is inverted in LyxyMNPV-5 relative to OlmeNPV. Pairwise nucleotide distances between OlmeNPV and other Lymantria spp. alphabaculoviruses indicate that OlmeNPV represents a new baculovirus species.


Assuntos
Mariposas , Nucleopoliedrovírus , Animais , Baculoviridae/genética , Genoma Viral , Nucleotídeos , Fases de Leitura Aberta , Filogenia
19.
Ecotoxicol Environ Saf ; 236: 113452, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35366565

RESUMO

Bt cotton successfully controlled major devastating pests in cotton,such as Helicoverpa armigera and Spodoptera exigua, and led to a drastic decrease in insecticide use in cotton fields, and it has been grown commercially worldwide. However, Bt cotton cultivation left Bt toxin residues in the soil, resulting in a response by its microbiome that caused potential environmental risks. In this research, the metagenomics analysis was performed to investigate the structure and functions of the soil bacterial community in the Bt cotton field from the Binzhou, Shandong province of China, where the Bt cotton has been cultivated for over fifteen years. Analysis of the function genes proved that the receptors of Bt toxins were absent in the soil bacteria and Bt toxins failed to target the soil bacteria. The microbiome structure and function were highly influenced by Bt cotton cultivation, however, no significant change in the total abundance of the bacteria was observed. Proteobacteria was the largest taxonomic group in the soil bacterial (42-52%) and its abundance was significantly increased after Bt cotton cultivation. The increase of Proteobacteria abundance resulted in an increase in ABC transporters gene abundance, indicating the improved ability of detoxification metabolism over Bt cotton cultivation. Xanthomonadales could be a biomarker of the Bt cotton group, whose abundance was significantly increased to contribute to the increase of the genes abundance in ABC transporters. The abundance of apoptosis genes was significantly decreased, and it might be related to the increase of Proteobacteria abundance by Bt cotton cultivation. In addition, Myxococcales was responsible for carotenoid biosynthesis, whoes genes abundance was significantly decreased due to the decrease of Myxococcales abundance by Bt cotton cultivation. These changes in soil bacterial community structure and functions indicate the influence by Bt cotton cultivation, leading to an understanding of the bacteria colonization patterns due to successive years of Bt cotton cultivation. These research results should be significant for the rational risk assessment of Bt cotton cultivation.


Assuntos
Toxinas de Bacillus thuringiensis , Mariposas , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Bactérias/genética , Proteínas de Bactérias/genética , Endotoxinas/genética , Gossypium/genética , Proteínas Hemolisinas/genética , Resistência a Inseticidas , Metagenômica , Mariposas/fisiologia , Plantas Geneticamente Modificadas/genética , Solo
20.
J Agric Food Chem ; 70(16): 4889-4898, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35416043

RESUMO

Chitinase is one of the most important glycoside hydrolyases, widely existing in bacteria, fungi, insects, and plants. It is involved in fungal cell wall remodeling and insect molting. Chitinase inhibitors are an effective means of controlling pathogens and pests. Natural product argifin is a 17-membered pentapeptide that exhibits efficient chitinase inhibitory activity. However, the complexity of the synthetic process results in a lot of restrictions for wide range of applications. In this work, we designed a series of azamacrolide chitinase inhibitors based on the structural features of argifin that have high inhibitory activities against bacterial and insectile chitinase. The most potent chitinase inhibitor compound 19c exhibited IC50 values of 56 nM and 110 nM against OfChi-h and SmChiB, respectively. The molecular docking and molecular dynamics simulations revealed that all inhibitors were bound to the -1 subsite of chitinases via N-methylcarbamoylguanidinyl as well as argifin. Finally, a bioactivity assay against pests was carried out. Compound 18a showed 80% mortality for Mythimna separata at a concentration of 50 mg/L. Besides, insecticides 19b and 19c exhibited high mortality against Plutella xylostella (76 and 73% mortalities at 50 mg/L, respectively).


Assuntos
Quitinases , Inseticidas , Mariposas , Animais , Quitinases/química , Inibidores Enzimáticos/química , Insetos/metabolismo , Inseticidas/farmacologia , Simulação de Acoplamento Molecular , Mariposas/metabolismo
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