Ionizing Radiations in Entomology

Radiation in the form of particles (α or β particles and neutrons) or electromagnetic waves (gamma or X-rays) can induce biological effects in insect cells like in other living cells. Ionization and chemical damages to organic molecules can be caused directly (mostly by particulate types of radiation) or indirectly by free radicals. Radioinduced ions and radicals, most of them coming from water radiolysis, may react with neighboring molecules to produce secondary DNA radicals or even chain reactions, particularly in lipids, and most of the significant biological effects results from damage to DNA. Currently, more than 300 species of arthropods, mostly of economic importance, have already been subjected to irradiation studies for basic research, pest control applications, and disinfestation of commodities (quarantine and phytosanitary purposes). This chapter focused on insect sterilization and disinfestation by ionizing radiations in view of the socioeconomic impacts. The release of insects that are sterile after exposure to radiation aiming to control or eradicate pest populations revealed to be a revolutionary tactic in the area-wide management of pests, and many successful cases with the application of the sterile insect technique can be found around the globe. The use of ionizing radiations to inhibit the spread of quarantine insects represents an important alternative postharvest control, and the development of generic radiation treatments has resulted in a significant increase in the international use of phytosanitary irradiation for trade in horticultural products and other commoditie

Alternative larval diets for mass rearing of screwworm, cochliomyia hominivorax

A criação massal da mosca da bicheira, Cochliomyia hominivorax (Diptera: Calliphoridae), para programas que utilizam a Técnica do Inseto Estéril nas Américas faz parte de um dos maiores programas do mundo de criação de insetos em larga escala. A maior parte do custo e do trabalho necessários para a produção massal está relacionada com a dieta larval, o que torna importante o seu aprimoramento levando-se em conta sua eficiência, custo e praticidade. Neste trabalho, foram realizados dois bioensaios com dietas alternativas feitas a partir de produtos disponíveis no mercado brasileiro com o objetivo de avaliar a viabilidade e eficiência dessas dietas para criações de mosca da bicheira no Brasil. Foram testadas duas dietas líquidas (tendo como bulking agents bagaço de cana ou fibra de coco), uma de carne, e outra de gel. Os parâmetros biológicos (peso das larvas, viabilidade larval, peso de pupas, porcentagem de emergência de adultos e razão sexual) estiveram, em todos os casos, dentro de parâmetros satisfatórios para a criação laboratorial de C. hominivorax e as dietas não diferiram estatisticamente entre si. Devido a vantagens importantes, como alta viabilidade larval e menor custo, recomenda-se a dieta de gel para as criações de larvas da mosca da bicheira no Brasil444672677CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informaçãoSem informaçãoThe mass rearing of the screwworm fly, Cochliomyia hominivorax (Diptera: Calliphoridae), for programs that integrate the Sterile Insect Technique in the Americas is part of one of the largest insect mass rearing programs in the world. Most of the cost and labor required in mass rearing systems is related to the larval diet, what enhances the relevance of the constant development of novel diets taking into account their effectiveness, cost and practicability. In this research, two bioassays with alternative diets made using local products were performed in order to evaluate the feasibility and efficiency of these diets for screwworm rearing in Brazil. Two liquid diets (having sugarcane bagasse or coconut fiber as bulking agents), a meat diet, and a gelled diet were tested. The biological parameters evaluated (larval weight, larval viability, pupal weight, adult emergence, and sex ratio) were satisfactory according to mass rearing standards and the diets did not differ statistically (P > 0.05). Due to its higher number of advantages, as high larval viability and lower cost, the gelled diet developed is recommended for screwworm larvae rearing in Brazi

Trophic ecology of citrus pests based on stable isotope analysis

Macrodactylus pumilio Burm. (Coleoptera: Scarabeidae) and Naupactus cervinus (Boh.) (Coleoptera: Curculionidae) are considered primary pests in citrus crops in Brazil, causing damage to plants and decreasing productivity. However, few studies investigate the ecology of these insects. In this context, the use of stable isotopes analysis (SIA) emerges as an alternative technique to conventional studies of behavioral ecology because it is faster and may explain feeding behavior based on the food source for each species. Field sampling and laboratory experiments were carried out to examine the changes of carbon and nitrogen stable isotope ratios (δ13C and δ15N) among pests and host plants (C3 citrus and C4 grasses), providing means to examine trophic interactions. Beetles were collected at the municipality of Gavião Peixoto, São Paulo State, identified and kept at 5 °C in saturated saline solution until the SIA. Two patterns for both species were found: δ13C value for N. cervinus was -23.6 ‰ and -13 ‰ for M. pumilio, indicating similarity between the results of δ13C of N. cervinus and citrus plants (-26 ‰) and dependence on grasses (-12 ‰) for M. pumilio individuals. The mean δ15N value was 4.3 and 5.8 ‰ for citrus plants and grass leaves, respectively, and the mean δ15N value was 4.4 ‰ for N. cervinus and 4.9 ‰ for M. pumilio. The results showed a higher affinity of N. cervinus for citrus roots since the larval stage compared with the alternative diet on M. pumilio

The host marking pheromone application on the management of fruit flies - a review

The aim of this work was to review the role of the host marking pheromone (HMP) and its application in integrated management programs for the fruit flies. Initially the oviposition behavior of tephritids has been analyzed with emphasis on Ceratitis capitata. The deposition of HMP, which consists in the last stage of the oviposition behavior has been characterized and discussed about evolutive aspects and the biological meaning of the tephritidae communication through the HMP. Finally, the perspectives on the use of HMP in the integrated management of fruit flies have been discussed

Invasion origin, rapid population expansion, and the lack of genetic structure of cotton bollworm (Helicoverpa armigera) in the Americas

In 2013, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) was officially declared as present in Brazil and, after two years, the species was detected in the Caribbean and North America. Information on genetic features and accurate distribution of pests is the basis for agricultural protection policies. Furthermore, such knowledge is imperative to develop control strategies, understand the geographical range, and genetic patterns of this species in the Americas. Here, we carried out the widest sampling of H. armigera in the South American continent and Puerto Rico, after we estimated the diversity, demographic parameters, and genetic structure. The Internal Transcribed Spacer 1 (ITS1) nuclear marker was used to investigate the presence of putative hybrids between H. armigera and H. zea, and they were observed at a frequency of 1.5%. An ABC analysis, based in COI gene fragment, suggested Europe as the origin of South America specimens of H. armigeraand following a movement northward through the Caribbean. Three mtDNA genes and three nDNA markers revealed high genetic diversity distributed without the defined population structure of H. armigera in South America. Most of the genetic variation is within populations with a multidirectional expansion of H. armigera among morphoclimatic regions. High genetic diversity, rapid population expansion, and hybridization have implications for pest management since they suggest that adaptive alleles are spread through wide areas in South America that favor rapid local adaptation of H. armigera to new and disturbed environments (e.g., in agricultural areas)9137378CAPES - Coordenação de Aperfeiçoamento de Pessoal e Nível SuperiorCNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2014/10504-9; 2014/11495-3; 2015/02079-9; 2018/04478-6140866/2016-7; 309167/2015-900

INHIBITION OF OVIPOSITION BY NEEM EXTRACT: A BEHAVIORAL PERSPECTIVE FOR THE CONTROL OF THE MEDITERRANEAN FRUIT FLY (DIPTERA: TEPHRITIDAE)

The behavioral inhibitory effect of methanol extracts from neem leaves (Azadirachta indica A. Juss) at different concentrations (0, 10,000, 18,000, 32,000 and 56,000 ppm) was evaluated using naive and experienced medflies (Ceratitis capitata (Wied.)) ovipositing on the fruits of grape cv. 'Italia'. The grapes were immersed in the specific treatments and were exposed for 24 h to 3 pairs of female and male medflies, both nave and experienced, in a choice test. At concentrations >= 18,000 ppm, the extract that was applied to the grapes inhibited oviposition. The previous experience with treated grapes did not affect the response of the medflies. This study is the first step toward the application of the behavior control of the medflies as a tool in grape vineyards. The potential for using oviposition inhibitory in behavioral control of C. capitata are discussed

Radiação Ionizante na Agroindústria: Revisão sobre as vantagens, efeitos e possibilidades de uso em alimentos de origem vegetal no Brasilno Brasil

Pesquisas e desenvolvimento de métodos que objetivem a redução de perdas e aumento da oferta de alimentos seguros e de qualidade para uma população mundial em expansão são necessários. A irradiação de alimentos é uma alternativa viável para promover a conservação de produtos de origem vegetal, com as finalidades de redução da contaminação causada por microrganismos patogênicos, aumento de vida útil dos alimentos, retardo do amadurecimento e diminuição das perdas pós-colheita. Como tratamento fitossanitário, pode ser utilizada visando atender aos requisitos do mercado internacional e às barreiras quarentenárias impostas pelos países importadores, não deixando resíduos tóxicos nos alimentos e não alterando significativamente suas propriedades sensoriais. No entanto, esse método ainda é subutilizado e pouco difundido no Brasil, e maiores investimentos são necessários para explorar mercados na área, tornando os produtos agropecuários mais competitivos internacionalmente