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1.
Plants (Basel) ; 13(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38674469

RESUMEN

Sesame, an oilseed plant with multiple applications, is susceptible to infestations by the stink bug Nezara viridula (Linnaeus, 1758) (Hemiptera: Pentatomidae). This pest suctions the seeds of this plant and injects toxins into them. Possible sources of resistance on sesame cultivars are important to manage this bug. The objective of this study was to evaluate the biological aspects of N. viridula fed on three sesame cultivars aiming to select possible resistance sources for integrated pest management (IPM) programs of this stinkbug. The experimental design used randomized blocks with three treatments and four replications, each with newly emerged N. viridula nymphs fed with sesame capsules of the cultivars BRS Anahí (T1), BRS Morena (T2) and BRS Seda (T3). Two to three green sesame capsules were supplied every two days per group of ten N. viridula nymphs as one replication until the beginning of the adult stage. Adults of this stinkbug were fed in the same manner as its nymphs but with mature sesame capsules until the end of the observations. Survival during each of the five instars and of the nymph stage of N. viridula with green sesame capsules was similar between cultivars, but the duration of the nymph stage was shorter with green capsules of the BRS Morena than with those of the BRS Anahí. The oviposition period, number of egg masses and eggs per female, and the percentage of nymphs hatched were higher with mature capsules of the sesame cultivar BRS Anahí and lower with the others. Nymphs did not hatch from eggs deposited by females fed mature seed capsules of the sesame cultivar BRS Morena, which may indicate a source of resistance against this stinkbug in this cultivar. The worldwide importance of N. viridula to sesame cultivation makes these results useful for breeding programs of this plant aiming to develop genotypes resistant to this bug. In addition, the BRS Morena is a cultivar already commercially available and can be recommended in places where there is a history of incidence of N. viridula, aiming to manage the populations of this pest.

2.
Plants (Basel) ; 13(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38498543

RESUMEN

The citrus blackfly (CBF), Aleurocanthus woglumi Ashby, is an exotic pest native to Southeast Asia that has spread rapidly to the world's main centers of citrus production, having been recently introduced to Brazil. In this study, a maximum entropy niche model (MaxEnt) was used to predict the potential worldwide distribution of CBF under current and future climate change scenarios for 2030 and 2050. These future scenarios came from the Coupled Model Intercomparison Project Phase 6 (CMIP6), SSP1-2.6, and SSP5-8.5. The MaxEnt model predicted the potential distribution of CBF with area under receiver operator curve (AUC) values of 0.953 and 0.930 in the initial and final models, respectively. The average temperature of the coldest quarter months, precipitation of the rainiest month, isothermality, and precipitation of the driest month were the strongest predictors of CBF distribution, with contributions of 36.7%, 14.7%, 13.2%, and 10.2%, respectively. The model based on the current time conditions predicted that suitable areas for the potential occurrence of CBF, including countries such as Brazil, China, the European Union, the USA, Egypt, Turkey, and Morocco, are located in tropical and subtropical regions. Models from SSP1-2.6 (2030 and 2050) and SSP5-8.5 (2030) predicted that suitable habitats for CBF are increasing dramatically worldwide under future climate change scenarios, particularly in areas located in the southern US, southern Europe, North Africa, South China, and part of Australia. On the other hand, the SSP5-8.5 model of 2050 indicated a great retraction of the areas suitable for CBF located in the tropical region, with an emphasis on countries such as Brazil, Colombia, Venezuela, and India. In general, the CMIP6 models predicted greater risks of invasion and dissemination of CBF until 2030 and 2050 in the southern regions of the USA, European Union, and China, which are some of the world's largest orange producers. Knowledge of the current situation and future propagation paths of the pest serve as tools to improve the strategic government policies employed in CBF's regulation, commercialization, inspection, combat, and phytosanitary management.

3.
Environ Sci Pollut Res Int ; 30(52): 111850-111870, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37848791

RESUMEN

Advances in agriculture include integrated methods of controlling pests, diseases, and weeds with biocontrollers, which are constantly increasing, along with herbicides. The objective is to present a systematic review of the main reports of herbicide effects on non-target organisms used in applied biological control and those naturally occurring in the ecosystems controlling pests. The categories were divided into predatory and parasitoid arthropods. Three hundred and fifty reports were analyzed, being 58.3% with parasitoids and 41.7% with predators. Lethal or sublethal effects of herbicides on reproduction, predation, genotoxicity, and abundance of biological control organisms have been reported. Two hundred and four reports of the impact of herbicides on parasitoids were analyzed. The largest number of reports was with parasitoids of the genus Trichogramma, with wide use in managing pests of the herbicide-tolerant transgenic plants. Most tests evaluating effects on parasitism, emergence, and mortality of natural enemies subjected to herbicides are with parasitoids of Lepidoptera eggs with a high diversity and use in managing these pests in different crops. Additive and synergistic effects of molecules increase the risks of herbicide mixtures. Herbicide use for weed management must integrate other control methods, as the chemical can impact natural enemies, reducing the biological control of pests.


Asunto(s)
Artrópodos , Herbicidas , Himenópteros , Lepidópteros , Animales , Herbicidas/farmacología , Ecosistema , Control Biológico de Vectores/métodos , Control de Malezas
4.
Heliyon ; 9(8): e18701, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37609418

RESUMEN

The Caribbean fruit fly Anastrepha suspensa (Diptera: Tephritidae) is a polyphagous pest causing economic losses in Central America, the Caribbean and South Florida. The parasitoid wasp Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is the main parasitoid of A. suspensa in biological control programs. In this study, by modeling with CLIMEX software, climatically suitable areas were projected according to historical climate data. Areas with overlapping optimal climatic suitability for the joint establishment of the pest and parasitoid were mapped, indicating large areas with host presence in North, Central, and South America, with cold stress being the main climatic factor limiting distribution for both species. Tropical regions have the most potential for invasion, with optimal suitability in many areas. Through the projected distributions, this study can target quarantine strategies in areas most susceptible to invasion and establishment of the pest in each country. In addition, classical biological control with the parasitoid in areas with climatic suitability is also recommended.

5.
Int J Biometeorol ; 67(7): 1185-1197, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37222775

RESUMEN

The Caribbean fruit fly, Anastrepha suspensa (Lower, 1862) (Diptera: Tephritidae), is a pest of significant economic importance in Central America and Florida (USA). This study was carried out to examine the influence of climate change on the space-time distribution of A. suspensa on temporal and spatial scales. The CLIMEX software was used to model the current distribution and for climate change. The future distribution was performed using two global climate models (GCMs), CSIRO-Mk3.0 (CS) and MIROC-H (MR), under the emission scenarios (SRES) A2 and A1B for the years 2050, 2080, and 2100. The results indicate a low potential for global distribution of A. suspensa in all scenarios studied. However, tropical areas were identified with high climatic suitability for A. suspensa in South America, Central America, Africa, and Oceania until the end of the century. Projections of areas with climatic suitability for A. suspensa can provide helpful information to develop preventive strategies of phytosanitary management avoiding economic impacts with the introduction of the species.


Asunto(s)
Tephritidae , Animales , Programas Informáticos , Predicción , Cambio Climático , América Central
6.
Pest Manag Sci ; 79(7): 2325-2337, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36799295

RESUMEN

BACKGROUND: Corn is one of the main crops grown globally to produce food for human consumption and animal feed, including raw materials for bioenergy. Effective pest management is critical for the economic viability of corn production. The leafhopper Dalbulus maidis and the diseases transmitted by it have become relevant to corn production. Our study aimed to determine environmental parameters that affect D. maidis populations and the impacts of pathogen dispersion on corn productivity under different rotation systems and sowing seasons. RESULTS: The population density of leafhoppers found in the studied crops was low but capable of establishing the diseases and spreading them widely in the crops. The leafhopper's highest occurrence was in the corn vegetative development stage, and its population peaks were earlier in the corn off-season. The incidence of maize rayado fino virus and maize bushy stunt phytoplasma were higher in corn off-season than in the growing season. The incidence of diseases was higher in the final stages of the cultivation cycle. Yield losses were significantly higher for maize bushy stunt phytoplasma and not significant for maize rayado fino virus. CONCLUSION: Our study observed that corn's physiological stage was the main factor influencing D. maidis dynamics. The occurrence of D. maidis at low densities was sufficient to ensure the efficient transmission and dissemination of maize rayado fino virus and maize bushy stunt phytoplasma, which had a higher incidence in the reproductive stage and the corn sowed off-season. © 2023 Society of Chemical Industry.


Asunto(s)
Hemípteros , Phytoplasma , Animales , Humanos , Zea mays , Phytoplasma/fisiología , Hemípteros/fisiología , Incidencia
7.
Plants (Basel) ; 12(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679066

RESUMEN

The fungus Austropuccinia psidii infects young tissues of Eucalyptus plants until they are two years old in the nursery and field, causing Myrtaceae rust. The characteristics making older eucalypt leaves resistant to A. psidii and the reason for the low levels of this pathogen in older plants need evaluations. The aim of this study was to evaluate the morphological differences between Eucalyptus grandis leaves of different growth stages and two plant ages to propose a visual phenological scale to classify E. grandis leaves according to their maturation stages and to evaluate the time of leaf maturation for young and adult plants. A scale, based on a morphological differentiation for E. grandis leaves, was made. The color, shape and size distinguished the leaves of the first five leaf pairs. Anatomical analysis showed a higher percentage of reinforced tissue, such as sclerenchyma-like tissue and collenchyma, greater leaf blade thickness, absence of lower palisade parenchyma in the mature leaves and a higher number of cavities with essential oils than in younger ones. Changes in anatomical characteristics that could reduce the susceptibility of older E. grandis leaves to A. psidii coincide with the time of developing leaf resistance. Reduced infection of this pathogen in older plants appears to be associated with a more rapid maturation of their leaf tissues.

8.
Environ Sci Pollut Res Int ; 29(15): 21803-21810, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34767175

RESUMEN

The aim of this study was to determine the 96-h LC50 (lethal concentration for 50% of the test population in 96 h of observation) of mercury chloride (HgCl2) and evaluated its absorption in the gills, liver, and muscle of juvenile "curimatã-pacu," Prochilodus argenteus. The fish were exposed for 4 days to different concentrations of HgCl2: 0.000, 0.0375, 00.075, 0.150, 0.225, 0.300, and 0.400 mg L-1 to get the 96-h LC50, and the concentration of Hg in the tissues. The fish were exposed to different levels of HgCl2 (0.000, 0.0375, 00.075, 0.150, 0.225, and 0.300 mg L-1), for 4 and 7 days, when different tissues (gills, liver, and muscle) were sampled. The mercury concentration values obtained were compared between tissues, days, and concentration of mercury in the water. The 96-h LC50 for P. argenteus was 0.339 mg L-1 of HgCl2, within the range found for other neotropical and tropical species, showing a medium sensitivity. The concentration of Hg in the tissues increased from the muscle to the gills and liver, and according to the increasing concentration of HgCl2 in the water. The fish liver is the most suitable tissue for environmental monitoring and for the evaluation of the consumed fished. Despite being the tissue that least accumulated mercury, the muscle must be evaluated because it is the part consumed by the population.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Animales , Brasil , Cloruros , Cloruro de Mercurio/toxicidad , Mercurio/análisis , Mercurio/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
9.
Insects ; 12(6)2021 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-34067273

RESUMEN

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is the main pest of maize crops, and effective methods for pest management are needed. The insecticidal efficacy of deltamethrin was evaluated against S. frugiperda for toxicity, survival, locomotion, anti-feeding, and histological changes in the midgut. Concentration-mortality bioassays confirmed that deltamethrin (LC50 = 3.58 mg mL-1) is toxic to S. frugiperda caterpillars. The survival rate was 99.7% in caterpillars not exposed to deltamethrin, decreasing to 50.3% in caterpillars exposed to LC50, and 0.1% in caterpillars treated with LC90. Spodoptera frugiperda demonstrated reduced mobility on deltamethrin-treated surfaces. Deltamethrin promoted a low respiration rate of S. frugiperda for up to 3 h after insecticide exposure, displaying immobilization and inhibiting food consumption. Deltamethrin induces histological alterations (e.g., disorganization of the striated border, cytoplasm vacuolization, and cell fragmentation) in the midgut, damaging the digestive cells and peritrophic matrix, affecting digestion and nutrient absorption.

10.
J Econ Entomol ; 114(4): 1631-1637, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-33959766

RESUMEN

The microlepidoptera, Bedellia somnulentella (Zeller), is an important pest of sweetpotato, Ipomoea batatas (L.) Lam. Damage by B. somnulentella occurs in the larval stage and when consuming the foliar mesophyll of I. batatas make the leaves brown, wrinkled, and reducing the photosynthetic area and the yield. The detection and management of this pest depends on knowing its biological cycle and identifying its natural enemies. The objectives of this study were to determine the life history of B. somnulentella feeding on I. batatas leaves and to survey parasitoids of this pest in the field. The duration and viability of B. somnulentella egg, larva, prepupa, pupa, and adult stages were evaluated under laboratory conditions. Cephalic capsule width was measured to determine the number of B. somnulentella instars, based on the Dyar rule and analyzed by the Akaike statistical model (AIC). The developmental period of B. somnulentella was 32.5 ± 0. 21 d with a viability of 75, 84, 100, and 84% for the egg, larva, prepupa, and pupa stages, respectively. The identification of this pest on the plants is possible from the third instar and in the pupal and adult stages. The parasitoid Conura sp. (Hymenoptera: Chalcididae) was identified parasitizing pupae of B. somnulentella and could be considered a potential natural enemy for the integrated management of this pest.


Asunto(s)
Convolvulaceae , Ipomoea batatas , Lepidópteros , Animales , Brasil , Larva , Control Biológico de Vectores , Hojas de la Planta , Pupa , Solanales
11.
Braz J Biol ; 81(2): 406-410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32428093

RESUMEN

The adaptation of native lepidopteran species to eucalyptus plantations reduces the productivity of this crop in Brazil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a secondary pest, frequently reported in eucalyptus plantations with population outbreaks and economic damages. Methods of biological control of this pest may include the use of the exotic pupae endoparasitoid Tetrastichus howardi Olliff (Hymenoptera: Eulophidae), reported as efficient to controlling lepidopteran pests. The parasitism of O. vesulia caterpillars and pupae by T. howardi was evaluated under controlled conditions (25 ± 1 ºC, 60 ± 20% humidity and 12:12 h L:D). Each O. vesulia caterpillar or pupae was individually placed in a flat-bottom tube with 10 and 15 females of T. howardi for 48h, respectively. The parasitoids were removed after that period, the caterpillars were fed and the pupae were maintained until emergence of the parasitoid or formation of pupae and emergence of adults of this pest. The fourth-instar caterpillars of O. vesulia, after the parasitism period, were kept in pots with Eucalyptus urophylla leaves, changed daily until the end of the experiment. A total of 40% of the caterpillars died before the pre-pupae stage, 40% reached the pupae stage and died due to inadequate adult formation and 20% generated moths, but none adult parasitoid emerged from the caterpillars. All pupae of O. vesulia were parasitized and showed emergence of parasitoids. The parasitism of O. vesulia caterpillars and pupae by T. howardi shows the potential of this natural enemy for the integrated management of this defoliator pest in eucalyptus plantations.


Asunto(s)
Eucalyptus , Himenópteros , Lepidópteros , Mariposas Nocturnas , Animales , Brasil , Femenino , Pupa
12.
Chemosphere ; 263: 128008, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32841879

RESUMEN

The anthranilic diamide, chlorantraniliprole is a systemic insecticide affecting ryanodine receptors. This insecticide is used to control caterpillars in soybean crops because it has low toxicity to non-target organisms. The objective was to identify side-effects of chlorantraniliprole on midgut histopathology, respiration and behavior of the velvetbean caterpillar Anticarsia gemmatalis in laboratoty. Chlorantraniliprole has LC50 = 0.61 (0.58-0.64) mg mL-1 for A. gemmatalis fourth instar caterpillars after 96 h. The insecticide causes severe histopathological effects in the midgut with epithelial disorganization, microvilli degeneration, cytoplasm vacuolization, cell fragmentation, and peritrophic matrix disorganization. The respiratory rate and the walking speed decrease, whereas the resting period increase for caterpillars exposed to this insecticide. Chlorantraniliprole is toxic to A. gemmatalis at median lethal concentrations causing severe histological and ultrastructural changes with degeneration of the midgut epithelium, reduction of respiratory rates and inducing an arresting behavioral response of this insect.


Asunto(s)
Insecticidas/toxicidad , Lepidópteros/fisiología , ortoaminobenzoatos/toxicidad , Animales , Sistema Digestivo , Larva , Locomoción/efectos de los fármacos , Microvellosidades , Mariposas Nocturnas , Respiración/efectos de los fármacos , Glycine max
13.
Rev. bras. entomol ; 65(2): e20210013, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1280017

RESUMEN

ABSTRACT The study of arthropod communities foraging on monocultures of native plants (e.g. Caryocar brasiliense) in biodiversity hotspots (e.g. Brazilian Cerrado) is important to understand the processes driving their performance. This study evaluated the possible interactions between galling herbivores, free-feeding arthropods, and of their natural enemies on C. brasiliense trees, in an orchard (monoculture). The possible competition observed were: i) between galling insects with defoliators and phytophagous mites, ii) between sucking insects, iii) between phytophagous mites and, iv) between Aphis gossypii (Hemiptera: Aphididae) with Histiostoma sp. (Acari: Histiostomidae) on C. brasiliense trees. Numbers of predators and prey, parasitoids and hosts, and predators and parasitoids were directly related among them. The competitive interactions between herbivorous predator and parasitoid may reduce Eurytoma sp. (Hymenoptera: Eurytomidae) populations, a potential pest of C. brasiliense. The predator Zelus armillatus (Hemiptera: Reduviidae) and the parasitoids Sycophila sp. (Hymenoptera: Eurytomidae) and Ablerus magistretti (Hymenoptera: Aphelinidae) are important to determine the numbers of Eurytoma sp. and of its galls. These natural enemies may be important to control this galling insect on C. brasiliense trees. The arthropod competition affected their guild associated to C. brasiliense trees.

14.
Braz. j. biol ; 81(2): 406-410, 2021. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1153373

RESUMEN

The adaptation of native lepidopteran species to eucalyptus plantations reduces the productivity of this crop in Brazil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) is a secondary pest, frequently reported in eucalyptus plantations with population outbreaks and economic damages. Methods of biological control of this pest may include the use of the exotic pupae endoparasitoid Tetrastichus howardi Olliff (Hymenoptera: Eulophidae), reported as efficient to controlling lepidopteran pests. The parasitism of O. vesulia caterpillars and pupae by T. howardi was evaluated under controlled conditions (25 ± 1 ºC, 60 ± 20% humidity and 12:12 h L:D). Each O. vesulia caterpillar or pupae was individually placed in a flat-bottom tube with 10 and 15 females of T. howardi for 48h, respectively. The parasitoids were removed after that period, the caterpillars were fed and the pupae were maintained until emergence of the parasitoid or formation of pupae and emergence of adults of this pest. The fourth-instar caterpillars of O. vesulia, after the parasitism period, were kept in pots with Eucalyptus urophylla leaves, changed daily until the end of the experiment. A total of 40% of the caterpillars died before the pre-pupae stage, 40% reached the pupae stage and died due to inadequate adult formation and 20% generated moths, but none adult parasitoid emerged from the caterpillars. All pupae of O. vesulia were parasitized and showed emergence of parasitoids. The parasitism of O. vesulia caterpillars and pupae by T. howardi shows the potential of this natural enemy for the integrated management of this defoliator pest in eucalyptus plantations.


A adaptação de espécies nativas de lepidópteros a plantios de eucalipto reduz a produtividade dessa cultura no Brasil. Oxydia vesulia Cramer (Lepidoptera: Geometridae) é praga-secundária, frequentemente, relatada em plantios de eucalipto com surtos populacionais e danos econômicos. Métodos de controle biológico, dessa praga, podem incluir o uso do endoparasitoide exótico de pupas Tetrastichus howardi Olliff (Hymenoptera: Eulophidae) relatado como eficiente para o controle de lepidópteros-pragas. O parasitismo de lagartas e pupas de O. vesulia por T. howardi foi avaliado em condições controladas (25 ± 1º C, 60 ± 20% umidade e 12h fotoperíodo). Cada lagarta ou pupa de O. vesulia foi colocada individualmente em tubos de fundo chato com 10 e 15 fêmeas de T. howardi por 48h, respectivamente e, após esse período, os parasitoides foram removidos, as lagartas alimentadas e as pupas mantidas até a emergência do parasitoide ou formação de pupas ou de adultos dessa praga. As lagartas de quarto ínstar de O. vesulia, após o período de parasitismo, foram mantidas em potes com folhas de Eucalyptus urophylla trocadas, diariamente, até o fim do experimento. Um total de 40% das lagartas de O. vesulia morreu antes da fase de pré-pupa, 40% atingiram o estágio de pupa e morreram devido à má formação ou problemas e 20% originaram mariposas, porém nenhum parasitoide adulto emergiu das lagartas. Todas as pupas de O. vesulia foram parasitadas e tiveram emergência de parasitoides. O parasitismo de lagartas e pupas de O. vesulia por T. howardi mostra o potencial desse inimigo natural para o manejo integrado desse desfolhador em cultivos de eucalipto.


Asunto(s)
Animales , Femenino , Eucalyptus , Himenópteros , Lepidópteros/parasitología , Mariposas Nocturnas , Pupa , Brasil
15.
Arq. Inst. Biol ; 88: e00182020, 2021. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1357872

RESUMEN

Sweet potato, Ipomoea batatas (L.) Lam (Convolvulaceae), is an essential crop for food security in developing countries. Euscepes postfasciatus (Fairmaire) (Coleoptera: Curculionidae) is one of the main pests of I. batatas in tropical and subtropical regions. It feeds on the tuberous roots of I. batatas and induces perforations tunnel-shaped with excrement. The objective of this study was to register, for the first time, the occurrence of E. postfasciatus in I. batatas in the municipality of Diamantina, Minas Gerais, Brazil. Individuals of E. postfasciatus were found in the larval, pupal and adult stages feeding on the roots, in the genotypes, Brasilândia Branca, Rubisol, UFVJM01, UFVJM02, UFVJM03, UFVJM04, UFVJM08, UFVJM18, UFVJM91, UFVJM291 and UFVJM526 in a greenhouse at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Euscepes postfasciatus injuries formed superficial and deep galleries with the presence of excrement and unpleasant odor. The record of E. postfasciatus in I. batatas in the municipality of Diamantina is important to develop local strategies for integrated pest management of the crop in the region.(AU)


Asunto(s)
Ipomoea , Gorgojos , Clima Tropical , Escarabajos , Plagas Agrícolas , Abastecimiento de Alimentos
16.
PLoS One ; 15(10): e0239285, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33006986

RESUMEN

Cleruchoides noackae (Hymenoptera: Mymaridae), native to Australia, is the most promising biological control agent for Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae), an exotic Eucalyptus spp. pest in Brazil. The aim of this study was to determine the courtship behaviour, mating and oviposition of unmated or mated C. noackae females parasitizing T. peregrinus eggs utilizing the same rearing system used in biological control programmes in Brazil. The mating behaviour of eleven C. noackae unmated couples was observed and the time taken for males and females to find each other in polystyrene vials and the duration and number of copulations were recorded. Ten unmated or mated females were placed individually in vials with 10 T. peregrinus eggs each, and oviposition behaviour, percentage of eggs inserted and parasitized, viability and sex ratio of emerged C. noackae were recorded. This species lacked defined courtship behaviour and mated in less than an hour after adults' emergence. The time spent finding the first host, evaluating and inserting the ovipositor was similar for mated and unmated C. noackae females, as well as the frequency of inserted and parasitized eggs and their viability. Mated females took less time to find other host eggs and the sex ratio is female-biased. Occurrence of arrhenotokous parthenogenesis was confirmed. The ability of C. noackae to mate and lay eggs in less than one hour and parasitism of T. peregrinus eggs by females can improve the parasitoid mass rearing and biological control of T. peregrinus.


Asunto(s)
Himenópteros/fisiología , Oviposición , Conducta Sexual Animal , Animales , Femenino , Masculino
17.
Sci Rep ; 10(1): 14617, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32883966

RESUMEN

Plants of the genus Eucalyptus, cultivated in many countries, have great importance for the world economy. In Brazil, this culture occupies a total of 5.7 million hectares, but native and exotic insect pests can reduce its productivity. Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae), an exotic Australian pest, damages Eucalyptus plants. Biological control using the egg parasitoid Cleruchoides noackae Lin & Huber (Hymenoptera: Mymaridae), Heteroptera predators and entomopathogenic fungi, such as Beauveria bassiana and Metarhizium anisopliae, have potential for managing T. peregrinus. Chemical insecticides, including bifenthrin and acetamiprid + bifenthrin, also control this insect. The compatibility of chemical and biological control methods favors integrated pest management. The objective of this study was to evaluate the selectivity of commercial products based on B. bassiana, M. anisopliae and the chemical bifenthrin on the parasitoid C. noackae and its parasitism on T. peregrinus eggs. The selectivity test followed the standards recommended by the International Organization for Biological Control (IOBC). Beauveria bassiana has selectivity to parasitism as well as viability, but was slightly harmful to C. noackae adults; M. anisopliae was innocuous to adults and to the viability of the offspring of this parasitoid, but it reduced the parasitism rate; and bifenthrin did not show selectivity to this parasitoid.


Asunto(s)
Eucalyptus/parasitología , Heterópteros/efectos de los fármacos , Insecticidas , Control Biológico de Vectores/métodos , Animales , Australia , Beauveria , Heterópteros/microbiología , Himenópteros , Metarhizium
18.
PLoS One ; 15(8): e0237261, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32804957

RESUMEN

Soil fertilization with dehydrated sewage sludge (DSS) accelerates the recovery process of degraded areas by improving nutrient concentration, and favors the development of trophic webs with pioneer plants such as Acacia auriculiformis A. Cunn. ex Beth (Fabales: Fabaceae), phytophagous Hemiptera, predators, and protocooperanting ants. This study aimed to evaluate the development and production of A. auriculiformis litter with or without dehydrated sewage sludge application and the ecological indices of sucking insects (Hemiptera), their predators and protocooperating ants, as bioindicators, in a degraded area for 24 months. Complete randomization was applied for two treatments (with or without application of dehydrated sewage sludge) in 24 replications (one repetition = one plant). We evaluated the number of leaves/branch and branches/plant, percentage of soil cover (litter), ecological indices of phytophagous Hemiptera, their predators, and protocooperating ants. The plants of A. auriculiformis, that were applied with dehydrated sewage sludge, had superior development when compared to plants where DSS were not applied. The highest abundance and richness of phytophagous Hemiptera species and Sternorrhyncha predators occurred on A. auriculiformis plants that were applied with dehydrated sewage sludge. The increase in richness of species of protocooperanting ants that established mutualistic relationships positively influenced the phytophagous Hemiptera. The use of A. auriculiformis, with application of dehydrated sewage sludge, can increase recovery of degraded areas due to its higher soil cover (e.g., litter) and results in higher ecological indices of phytophagous Hemiptera and their predators.


Asunto(s)
Acacia/fisiología , Fertilizantes , Hemípteros/fisiología , Aguas del Alcantarillado/química , Suelo/química , Animales , Hormigas/fisiología , Biodiversidad , Fertilizantes/análisis , Cadena Alimentaria , Agua/química
19.
Sci Rep ; 10(1): 12395, 2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32709920

RESUMEN

Insecticides are the main method of controlling lepidopteran pests of eucalyptus plantations and those selective to natural enemies, such as the endoparasitoid Palmistichus elaeisis Delvare et LaSalle (Hymenoptera: Eulophidae), are preferable. The objective of this study was to evaluate the selectivity and effects on biological parameters of the insecticide deltamethrin, registered for the control of defoliator caterpillars of eucalyptus, to the parasitoid P. elaeisis aiming the rational use of this insecticide and its compatibility with parasitoids. The experiment was in a completely randomized design. The treatments were the doses of 0.64, 1.40, 3.10, 6.83, 15.03, 33.05, 72.7 and 160 mg a.i./L of deltamethrin and the control (distilled water) with 10 replications, each with a pupae of the alternative host Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae) exposed by the immersion method. The parasitism, biological cycle, emergence, longevity, head width and metatibia length of the natural enemy were evaluated. Deltamethrin reduced parasitism and the emergence rates of P. elaeisis. The duration of the biological cycle of this parasitoid, emerged from T. molitor pupae exposed to 15.03 mg a.i./L of deltamethrin, was higher. The morphometric parameters of P. elaeisis exposed to the doses of 0.64 and 1.40 mg a.i./L of the insecticide were lower. However, the morphometric parameter values were higher with the doses above 3.10 mg a.i./L than in the control. The parasitism and emergence of P. elaeisis were also reduced by the deltamethrin doses lower than the commercially recommended one and therefore, this insecticide is not selective for this natural enemy.


Asunto(s)
Himenópteros/fisiología , Insecticidas , Nitrilos , Piretrinas , Tenebrio/parasitología , Animales , Relación Dosis-Respuesta a Droga
20.
Sci Rep ; 10(1): 11811, 2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32678241

RESUMEN

Nutrients from dehydrated sewage sludge play an essential role in the development of many plants such as Terminalia argentea, in the recovery of degraded areas. The aims were to assess the abundance, diversity and species richness of phytophagous, pollinators and predators arthropods, as well as the percentage of defoliation of T. argentea trees, fertilized (or not) with dehydrated sewage sludge in a degraded area. The abundance, diversity and species richness of phytophagous Coleoptera and total predators (predator insects + protocooperating ants + spiders); abundance and species richness of Diptera, pollinator insects, spiders, and predators (predator insects + spiders) were higher on trees fertilized with dehydrated sewage sludge. The abundance of phytophagous Coleoptera declined with the presence of phytophagous Hemiptera and protocooperating ants; population of phytophagous Orthoptera declined in response to phytophagous Coleoptera and total predators; the numbers of the leafminer Lyriomyza sp. directly increased with the numbers of spiders. The ecological indices of phytophagous, pollinators, and predator arthopods increased on Terminalia argentea trees fertilized with dehydrated sewage sludge; such a better ecological indices in fertilized than in unfertilized trees, show it more suitable for the recovery of degraded areas. We discuss the competition between phytophagous insects groups as well as herbivory reduction by predators.


Asunto(s)
Artrópodos , Ambiente , Monitoreo del Ambiente , Fertilización , Aguas del Alcantarillado , Terminalia , Animales , Biodiversidad , Insectos , Conducta Predatoria , Terminalia/parasitología
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