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Gustavo Ferreira Martins

Bio: Gustavo Ferreira Martins is an academic researcher from Universidade Federal de Viçosa. The author has contributed to research in topics: Aedes aegypti & Midgut. The author has an hindex of 24, co-authored 106 publications receiving 1719 citations. Previous affiliations of Gustavo Ferreira Martins include University of the Azores & Oswaldo Cruz Foundation.


Papers
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Journal ArticleDOI
TL;DR: The V410L mutation drastically reduced the sensitivity of mosquito sodium channels expressed in Xenopus oocytes to both type I and type II pyrethroids and presents a serious challenge for the control of A. aegypti in Brazil.
Abstract: The yellow fever mosquito, Aedes aegypti, particularly in Neotropical regions, is the principal vector of dengue, yellow fever, Zika and Chikungunya viruses. Pyrethroids remain one of the most used insecticides to control Aedes mosquitoes, despite the development of pyrethroid resistance in many mosquito populations worldwide. Here, we report a Brazilian strain of A. aegypti with high levels (approximately 100-60,000 fold) of resistance to both type I and type II pyrethroids. We detected two mutations (V410L and F1534C) in the sodium channel from this resistant strain. This study is the first report of the V410L mutation in mosquitoes. Alone or in combination with the F1534C mutation, the V410L mutation drastically reduced the sensitivity of mosquito sodium channels expressed in Xenopus oocytes to both type I and type II pyrethroids. The V410L mutation presents a serious challenge for the control of A. aegypti and will compromise the use of pyrethroids for the control of A. aegypti in Brazil; therefore, early monitoring of the frequency of the V410L mutation will be a key resistance management strategy to preserve the effectiveness of pyrethroid insecticides.

136 citations

Journal ArticleDOI
04 Jun 2012-PLOS ONE
TL;DR: The lethal effects of imidacloprid on native stingless bees are demonstrated and evidence of novel serious sublethal effects that may compromise colony survival is provided.
Abstract: Declines in pollinator colonies represent a worldwide concern. The widespread use of agricultural pesticides is recognized as a potential cause of these declines. Previous studies have examined the effects of neonicotinoid insecticides such as imidacloprid on pollinator colonies, but these investigations have mainly focused on adult honey bees. Native stingless bees (Hymenoptera: Apidae: Meliponinae) are key pollinators in neotropical areas and are threatened with extinction due to deforestation and pesticide use. Few studies have directly investigated the effects of pesticides on these pollinators. Furthermore, the existing impact studies did not address the issue of larval ingestion of contaminated pollen and nectar, which could potentially have dire consequences for the colony. Here, we assessed the effects of imidacloprid ingestion by stingless bee larvae on their survival, development, neuromorphology and adult walking behavior. Increasing doses of imidacloprid were added to the diet provided to individual worker larvae of the stingless bee Melipona quadrifasciata anthidioides throughout their development. Survival rates above 50% were only observed at insecticide doses lower than 0.0056 µg active ingredient (a.i.)/bee. No sublethal effect on body mass or developmental time was observed in the surviving insects, but the pesticide treatment negatively affected the development of mushroom bodies in the brain and impaired the walking behavior of newly emerged adult workers. Therefore, stingless bee larvae are particularly susceptible to imidacloprid, as it caused both high mortality and sublethal effects that impaired brain development and compromised mobility at the young adult stage. These findings demonstrate the lethal effects of imidacloprid on native stingless bees and provide evidence of novel serious sublethal effects that may compromise colony survival. The ecological and economic importance of neotropical stingless bees as pollinators, their susceptibility to insecticides and the vulnerability of their larvae to insecticide exposure emphasize the importance of studying these species.

126 citations

Journal ArticleDOI
TL;DR: Findings indicate the hazardous nature not only of imidacloprid but also the bioinsecticide spinosad to adult workers of the native pollinator M. quadrifasciata and Bioinsecticides should not be exempted from risk assessment analysis due to their lethal and sublethal components.

82 citations

Journal ArticleDOI
TL;DR: The current literature on stingless bee-agrochemical interactions is reviewed and the underlying mechanisms involved in reported stress symptoms, as well as the potential consequences based on the peculiarities of these pollinators are discussed.
Abstract: The toxicological stress induced by pesticides, particularly neonicotinoid insecticides, and its consequences in bees has been the focus of much recent attention, particularly for honey bees. However, the emphasis on honey bees and neonicotinoids has led to neglect of the relevance of stingless bees, the prevailing pollinators of natural and agricultural tropical ecosystems, and of other agrochemicals, including other pesticides and even leaf fertilizers. Consequently, studies focusing on agrochemical effects on stingless bees are sparse, usually limited to histopathological studies, and lack a holistic assessment of the effects of these compounds on physiology and behavior. Such effects have consequences for individual and colony fitness and are likely to affect both the stingless bee populations and the associated community, thereby producing a hierarchy of consequences thus far overlooked. Herein, we review the current literature on stingless bee-agrochemical interactions and discuss the underlying mechanisms involved in reported stress symptoms, as well as the potential consequences based on the peculiarities of these pollinators.

79 citations

Journal ArticleDOI
TL;DR: In vitro rearing of worker honey bees from larvae to adult emergence can be implemented as the standard protocol to determine the impact of pesticides on immature bees because of the protocol’s high control survivability, ease in end point determination, and high overall repeatability.
Abstract: The in vitro rearing of worker honey bees (Apis mellifera L.) has become an increasingly important method in honey bee research in general, and in pesticide risk assessment specifically. Authorities from the European Organization for Economic Co-operation and Development and the United States Environmental Protection Agency are requesting data on pesticide impacts on immature bee survivorship prior to registering new crop protection products. Those using the current in vitro rearing protocols have had variable success with immature bee survival and protocol repeatability. Here, we present an improved method for the in vitro rearing of worker honey bees from larvae to adult emergence. We have achieved consistently high survival (>95%) in our control and solvent-control rearing trials. Changes in the proportion of diet components, royal jelly source, maintenance of the developing bee, and rearing environment are the main contributors for our high rearing success and are discussed herein. Our in vitro rearin...

74 citations


Cited by
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01 Jan 1999
TL;DR: Caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases as discussed by the authors, and they play critical roles in initiation and execution of this process.
Abstract: ■ Abstract Apoptosis is a genetically programmed, morphologically distinct form of cell death that can be triggered by a variety of physiological and pathological stimuli. Studies performed over the past 10 years have demonstrated that proteases play critical roles in initiation and execution of this process. The caspases, a family of cysteine-dependent aspartate-directed proteases, are prominent among the death proteases. Caspases are synthesized as relatively inactive zymogens that become activated by scaffold-mediated transactivation or by cleavage via upstream proteases in an intracellular cascade. Regulation of caspase activation and activity occurs at several different levels: ( a) Zymogen gene transcription is regulated; ( b) antiapoptotic members of the Bcl-2 family and other cellular polypeptides block proximity-induced activation of certain procaspases; and ( c) certain cellular inhibitor of apoptosis proteins (cIAPs) can bind to and inhibit active caspases. Once activated, caspases cleave a variety of intracellular polypeptides, including major structural elements of the cytoplasm and nucleus, components of the DNA repair machinery, and a number of protein kinases. Collectively, these scissions disrupt survival pathways and disassemble important architectural components of the cell, contributing to the stereotypic morphological and biochemical changes that characterize apoptotic cell death.

2,685 citations

Proceedings Article
27 Aug 1984

954 citations

Journal ArticleDOI
23 Nov 1935-Nature
TL;DR: The Principles of Insect Morphology by R. E. Snodgrass as discussed by the authors is one of the most important works in the field of insect morphology, and it has been widely used in the literature.
Abstract: THE author of this book ranks as the foremost American worker on insect morphology. His contributions on the subject are notable for their clarity and originality of thought, and the appearance of a volume, embodying his ideas in comprehensive form, is sure of a hearty welcome. In its preparation, Mr. Snodgrass has incorporated the results of much first-hand study with those of many recent investigators in the same field. He has produced an outstanding book wherein knowledge of facts is combined with that of function and, at the same time, theoretical conceptions of the origins and relationships of organs and parts are not overlooked. Principles of Insect Morphology By R. E. Snodgrass. (McGraw-Hill Publications in the Zoological Sciences.) Pp. ix + 667. (New York and London: McGraw-Hill Book Co., Inc., 1935.) 36s. net.

770 citations

Journal ArticleDOI
TL;DR: Enough knowledge exists to conclude that existing levels of pollution with neonicotinoids and fipronil resulting from presently authorized uses frequently exceed the lowest observed adverse effect concentrations and are thus likely to have large-scale and wide ranging negative biological and ecological impacts on a wide range of non-target invertebrates in terrestrial, aquatic, marine and benthic habitats.
Abstract: We assessed the state of knowledge regarding the effects of large-scale pollution with neonicotinoid insecticides and fipronil on non-target invertebrate species of terrestrial, freshwater and marine environments. A large section of the assessment is dedicated to the state of knowledge on sublethal effects on honeybees (Apis mellifera) because this important pollinator is the most studied non-target invertebrate species. Lepidoptera (butterflies and moths), Lumbricidae (earthworms), Apoidae sensu lato (bumblebees, solitary bees) and the section “other invertebrates” review available studies on the other terrestrial species. The sections on freshwater and marine species are rather short as little is known so far about the impact of neonicotinoid insecticides and fipronil on the diverse invertebrate fauna of these widely exposed habitats. For terrestrial and aquatic invertebrate species, the known effects of neonicotinoid pesticides and fipronil are described ranging from organismal toxicology and behavioural effects to population-level effects. For earthworms, freshwater and marine species, the relation of findings to regulatory risk assessment is described. Neonicotinoid insecticides exhibit very high toxicity to a wide range of invertebrates, particularly insects, and field-realistic exposure is likely to result in both lethal and a broad range of important sublethal impacts. There is a major knowledge gap regarding impacts on the grand majority of invertebrates, many of which perform essential roles enabling healthy ecosystem functioning. The data on the few non-target species on which field tests have been performed are limited by major flaws in the outdated test protocols. Despite large knowledge gaps and uncertainties, enough knowledge exists to conclude that existing levels of pollution with neonicotinoids and fipronil resulting from presently authorized uses frequently exceed the lowest observed adverse effect concentrations and are thus likely to have large-scale and wide ranging negative biological and ecological impacts on a wide range of non-target invertebrates in terrestrial, aquatic, marine and benthic habitats.

649 citations

Journal ArticleDOI
TL;DR: The present review mitigates this shortcoming by hierarchically exploring within an ecotoxicology framework applied to integrated pest management the myriad effects of insecticide use on arthropod pest species.
Abstract: More than six decades after the onset of wide-scale commercial use of synthetic pesticides and more than fifty years after Rachel Carson's Silent Spring, pesticides, particularly insecticides, arguably remain the most influential pest management tool around the globe. Nevertheless, pesticide use is still a controversial issue and is at the regulatory forefront in most countries. The older generation of insecticide groups has been largely replaced by a plethora of novel molecules that exhibit improved human and environmental safety profiles. However, the use of such compounds is guided by their short-term efficacy; the indirect and subtler effects on their target species, namely arthropod pest species, have been neglected. Curiously, comprehensive risk assessments have increasingly explored effects on nontarget species, contrasting with the majority of efforts focused on the target arthropod pest species. The present review mitigates this shortcoming by hierarchically exploring within an ecotoxicology fram...

456 citations