Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-09-28T18:12:13Z No. of bitstreams: 2 Marilia_Favalesso_2018.pdf: 1901703 bytes, checksum: 0d9b6ae60903ec7aa858792cf86a51f2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-28T18:12:13Z (GMT). No. of bitstreams: 2 Marilia_Favalesso_2018.pdf: 1901703 bytes, checksum: 0d9b6ae60903ec7aa858792cf86a51f2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Lonomia obliqua Walker 1855 (Saturniidae: Hemileucinae) is a species of moth of sanitary interest in Brazil. Their larvae are etiological agents of lonomism, a form of erucism caused by the contact of the human beings with the stinging structures of the species. The most worrying symptoms of lonomism are the systemic hemorrhagic conditions that can lead to several outcomes, including death. The first official notifications of accidents with the species date back to the end of the 80s, in the state of Rio Grande do Sul. Since then, several accidents have been documented in Brazil, mainly in the south and southeast regions of the country. With the increase in the number of victims, health authorities in the state of São Paulo, represented by the “Instituto Butantã”, developed an anti-lonomic serum, which is distributed by the Ministry of Health in places with a higher prevalence of accidents. Hypotheses have been raised on the relation between the growth of the cases of lonomismo and the human occupation; however, little is known about the spatial distribution and ecological aspects of the species to enable the testing of these hypotheses. In view of the above, the present study aimed to produce a map for the potential geographical distribution of L. obliqua in Brazil, based on the combination of different ENM (Ecological Niche Modeling) algorithms. A total of 38 occurrence points were distributed across the geographic area of Brazil and Misiones, Argentina, which were partitioned for calibration and evaluation of the distribution model. Eight continuous climatic variables and only 16 previously considered variables were selected. Different ENM methodologies were tested and compared to TSS (True Skill Statistic) index values. The final model-map was composed of a combination of four algorithms (Gower, Mahalanobis, Maxent and SVM), with pseudo-absences outside a bioclimatic envelope and a number of pseudo-absences equal to that of presences. This model map was binarized from the Low Presence Threshold (LPT) and cut only for Brazil. According to this model map, the areas predicted as suitable for L. obliqua would be restricted to latitudes ~12° and ~32°, and longitudes ~39° and ~57°. When evaluating new sites of occurrence of the specie in Rio Grande do Sul, it was possible to verify that all the municipalities were in areas predicted by the model-map. A characterization of the abiotic variables related to the niche of the specie was also carried out, being these extracted from the area predicted as adequate the presence of the specie in the model map. To help characterize these variables, we also extract categorical descriptors of climate, soil and vegetation (in %). The percentage of land use classes was also extracted in order to contribute to the hypothesis that condition the increase of accidents due to human occupation. In this question, we find a large part of the area predicted within classes of agricultural soils in Brazil, which leads us to ratify the current hypotheses. Thus, the loss of habitat of the species for the agricultural enterprises increases the human contact with the specie, which should increase the number of notifications of the lonomism, generating greater epidemiological concern and habitat conservation for this specie. / Lonomia obliqua Walker 1855 (Saturniidae: Hemileucinae) é uma espécie de mariposa de interesse sanitário no Brasil. Suas larvas são agentes etiológicos do lonomismo, uma forma de erucismo causado pelo contato dos seres humanos com as estruturas urticantes da espécie. Os sintomas mais preocupantes do lonomismo são os quadros hemorrágicos sistêmicos que podem conduzir a diversos desfechos, inclusive o óbito. As primeiras notificações oficiais de acidentes com a espécie datam do final da década de 80, no estado do Rio Grande do Sul. A partir de então, diversos acidentes têm sido documentados no Brasil, principalmente nas regiões sul e sudeste do país. Com o aumento do número de vítimas, autoridades sanitárias do estado de São Paulo, representadas pelo do Instituto Butantã, desenvolveram um soro antilonômico, o qual é distribuído pelo Ministério da Saúde em localidades com maior prevalência de acidentes. Hipóteses têm sido levantadas sobre a relação entre o crescimento dos casos de lonomismo e a ocupação humana; contudo, pouco se conhece sobre a distribuição espacial e aspectos ecológicos da espécie para possibilitar os testes destas hipóteses. Diante do exposto, o presente estudo objetivou produzir um mapa para a distribuição geográfica potencial de L. obliqua no Brasil, baseando-se na combinação de diferentes algoritmos ENM (Ecological Niche Modeling). Foram utilizados 38 pontos de ocorrência distribuídos pela área geográfica do Brasil e região de Misiones, na Argentina, os quais foram particionados para calibração e avaliação do modelo de distribuição. Foram selecionadas oito variáveis contínuas climáticas e de solo entre 16 previamente cogitadas. Diferentes metodologias ENM foram testadas e confrontados quanto a valores de índice TSS (True Skill Statistic). O mapa-modelo final foi composto por uma combinação de quatro algoritmos (Gower, Mahalanobis, Maxent e SVM), com amostragens de pseudo-ausências fora de um envelope bioclimático e número de pseudo-ausências igual ao de presenças. Esse mapa-modelo foi binarizado a partir do limiar LPT (Lowest Presence Threshold) e recortado somente para o Brasil. Segundo este mapa-modelo, as áreas preditas como adequáveis a L. obliqua estariam restritas as latitudes ~12º e ~32º, e as longitudes ~39º e ~57º. Também foi realizada uma caracterização das variáveis abióticas relacionadas ao nicho da espécie, sendo essas extraídas da área predita como adequada a presença da espécie no mapa-modelo. O percentual de classes de uso da terra também foi extraído, a fim de contribuir com as hipóteses que condicionam o aumento de acidentes em função da ocupação humana. Neste quesito, encontramos grande parte da área predita dentro de classes de solos agrícolas no Brasil, o que nos leva a ratificar as hipóteses atuais. Assim, a perda de habitat da espécie para os empreendimentos agrícolas aumenta o contato humano com a espécie, o que deve aumentar o número de notificações do lonomismo, gerando maior preocupação a nível epidemiológico e de conservação de habitat para essa espécie.

Les insectes phytophages forment un groupe d’organismes très diversifié et la plupart sont considérés comme spécialistes. Les patrons de spécialisation des insectes vis à vis de leurs plantes hôtes dépendent en partie de leur capacité à interagir avec les plantes (niche fondamentale) et aux facteurs environnementaux modulant ces interactions et aboutissant aux observations en milieu naturel (niche réalisée). La spécialisation fondamentale est déterminée par l'évolution conjointe de deux traits : la performance des larves et la préférence des femelles. Pour comprendre cette spécialisation, nous avons étudié une communauté de huit espèces de mouches des fruits (Diptera : Tephritidae) présentes à La Réunion. Dans un premier temps, nous avons déterminé la niche réalisée de chaque espèce et montré que ces niches étaient structurées par la phylogénie des plantes avec D. demmerezi, D. ciliatus et Z. cucurbitae spécialistes des Cucurbitaceae, N. cyanescensspécialiste des Solanaceae et C. catoirii, C. capitata et C. quilicii généralistes attaquant des plantes de différentes familles. Après l'invasion de B. zonata en 2000, C. capitata et C. quilicii ont subi une réduction de leur gamme d'hôtes. Dans un deuxième temps, nous avons déterminé la niche fondamentale de ces espèces (sauf D. ciliatus). Nous avons évalué les préférences des femelles en mesurant la fécondité de chacune d’entre elles sur une gamme de 29 fruits, puis nous avons testé l'existence d'une corrélation entre la préférence des femelles et la performance des larves (mother knows best hypothesis). Nous avons montré une corrélation positive chez spécialistes des Cucurbitaceae qui pondent sur les plantes pour lesquelles les larves survivent le mieux contrairement aux généralistes pondant et survivant sur une large gamme d'hôtes mais sans corrélation entre ces deux traits.Enfin, la sélection de l'hôte par les femelles se faisant principalement grâce aux composés organiques volatils (COVs) émis par les fruits, nous avons montré que les fruits infestés par les généralistes ont pour point commun l'émission de COVs responsables de la maturation des fruits. Au contraire, les fruits de plusieurs Solanaceae émettent des COVs spécifiques suggérant la détection de ceux-ci par les femelles de N. cyanescens. Les Cucurbitaceae émettent des COVs abondants peu présents dans les autres familles suggérant une détection d'un mélange spécifique de ces COVs par les Tephritidae spécialistes des Cucurbitaceae. / Phytophagous insects are a very diverse group of organisms and most of them are considered as specialized. Patterns of specialization regarding their host plants depend on their ability to interact with their hosts (fundamental niche) and on environmental factors which modulate these interactions leading to observed patterns in the field (realized niche). Fundamental specialization is determined by the joint evolution of two traits: larval performance and female preference. To understand this specialization, we studied a community of eight fruit fly species (Diptera: Tephritidae) present in La Réunion.First, we determined the realized niche of each species and showed that they were structured by plant phylogeny with D. demmerezi, D. ciliatus and Z. cucurbitae as Cucurbitaceae specialists, N. cyanescens as Solanaceae specialist and C. catoirii, C. capitata et C. quilicii as generalists feeding on plants belonging to different families. After the invasion of B. zonata in 2000, C. capitata et C. quilicii were subjected to a decrease of their host range.Then, we determined the fundamental niche of these species (except D. ciliatus). We assessed female preferences by measuring their fecundity on 29 fruits, then we tested the presence of a correlation between female preference and larval performance (mother knows best hypothesis). We showed a positive correlation for Cucurbitaceae specialists laying eggs on plants where larvae survive the best, at the opposite of generalist species laying eggs and surviving on many hosts without any correlation between these two traits.Finally, host selection by females being mostly done thanks to volatile organic compounds (VOCs) emitted by fruits, we showed that fruits infested by generalist species have common VOCs responsible for fruit maturation. On the contrary, the fruits of several Solanaceae emit specific VOCs suggesting their detection by N. cyanescens females. Cucurbitaceae species emit abundant VOCs rarely present in other families suggesting a detection of a specific blend of these VOCS by Cucurbitaceae specialists.