Apresenta-se nesta tese os resultados de aplicações do formalismo da Mecânica Estatística em dois problemas independentes. O primeiro diz respeito a um modelo para Evolução do Acasalamento Preferencial no processo de Especiação Simpátrica; enquanto que o segundo refere-se ao desenvolvimento de um algoritmo de aprendizado por meio de Inferência Aproximativa. No problema biológico estudado, cada indivíduo em um modelo de agentes é composto por dois traços. Enquanto um é responsável pela ecologia do indivíduo, o outro dita uma aparência física descorrelacionada com a adaptabilidade. Esses traços são expressos por diferentes loci que estão ligados entre si por uma taxa de recombinação. O modelo inclui também a possibilidade de evolução da preferência sexual dos indivíduos. Foi construído para esse modelo um diagrama de fases no espaço dos parâmetros que descrevem o ambiente como, por exemplo, quantidades de recursos e deficiência do indivíduo híbrido. Foram encontradas três fases de equilíbrio: (i) emergência de Acasalamento Preferencial; (ii) extinção de um dos alelos do locus responsável pela ecologia e (iii) equilíbrio Hardy-Weinberg. Foi verificado que o acasalamento preferencial pode emergir ou mesmo ser perdido (e vice-versa) em resposta a mudanças no ambiente. Além disso, o sistema apresenta memória característica típica de transições de primeira ordem, o que permitiu a descrição desse sistema biológico por meio do arcabouço da Mecânica Estatística. Em relação à Inferência Aproximativa, está-se interessado na construção de um algoritmo de aprendizado supervisionado por meio da técnica de Propagação de Expectativas. Mais especificamente, pretende-se inferir os parâmetros que compõem um Perceptron Professor a partir do conjunto de pares - entradas e saídas - que formam o conjunto de dados disponíveis. A estimativa desses parâmetros será feita pela substituição de uma distribuição Posterior original, geralmente intratável, por uma distribuição aproximativa tratável. o algoritmo Propagação de Expectativas foi adotado para a atualização, passo a passo, dos termos que compõem essa distribuição aproximativa. Essa atualização deve ser repetida até que a convergência seja atingida. Utilizando o Teorema do Limite Central e o método de Cavidade, foi possível obter um algoritmo genérico e que apresentou desempenho bastante evidente em dois modelos estudados: o modelo do Perceptron Binário e o modelo do Perceptron Gaussiano, com desempenho ótimo em ambos os casos. / This thesis presents applications of the framework of Statistical Mechanics to two independent problems. The first corresponds to a computational model for the evolution of Assortative Mating in the Sympatric Speciation process; and the second a learning algorithm built by means of a Bayesian Inference approach. In the biological problem each individual in an agent-based model is composed of two traits. One trait, called the ecological trait, is directly related with the fitness; the other, called the marker trait, has no bearing on the fitness. The traits are determined by different loci which are linked by a recombination rate. There is also the possibility of evolution of mating preferences, which are inherited from the mother and subject to random variations. The study of the phase diagram in the spa e of parameters describing the environment (like carrying capacity and disruptive selection) reveals the existence of three phases: (i) assortative mating; (ii) extinction of one allele from ecological loci; and (iii) Hardy-Weinberg equilibrium. It was verifed that the assortative mating an emerge or even be lost (and vice-versa) acording with the environmental hanges. Moreover, the system shows memory of the initial condition, characterising a hysteresis. Hysteresis is the signature of first order phase transition, which allows the description of the system by means of the Statistical Mechanics framework. In relation to the Bayesian Inference, a supervised learning algorithm was constructed by means of the Expectation Propagation approach. The idea is to estimate the parameters which compose a Teacher Perceptron by the substitution of the original posterior distribution, intra table, by a tractable approximative distribution. The step-by-step update of the terms composing the approximative distribution was performed by using the Expectation Propagation algorithm. The update must be repeated until the convergence ocurrs. Using the Central Limit Theorem and the Cavity Approah, it was possible to get a generic algorithm that has shown a very good performance in two application scenarios: The Binary Perceptron Model and the Gaussian Perceptron Model.

Je m’intéresse à l’écologie évolutive et en particulier à l’évolution des systèmes de reproduction, à l’adaptation et aux interactions de ces deux processus. En effet, les modèles théoriques ainsi qu’un certain nombre d’observations en populations naturelles soulignent que le système de reproduction devrait avoir un effet majeur sur les processus évolutifs et démographiques en populations naturelles. Lors de ma thèse, j’aborde ces thèmes sous divers angles à partir d’une Brassicacée tolérante et hyper-accumulatrice aux métaux lourds, Noccaea caerulescens, et à partir de modèles théoriques. Dans un premier temps, je m’intéresse à la variation du système de reproduction en populations naturelles. Comment s’organisent les flux de gènes entre populations ou sous-populations, et entre individus d’une même population ? Je me suis particulièrement intéressée à l’influence de la pollution des sols sur le taux d’autofécondation chez N. caerulescens, aux flux de gènes entre populations vivant dans les mines et populations vivant sur des sols non contaminés, et à la structure à l’intérieur des populations. Afin de mieux comprendre les facteurs influençant le système de reproduction, j’ai ensuite testé l’effet de la densité en plantes sur le taux d’autofécondations en populations naturelles. Dans un second temps, je teste les interactions existant entre adaptation à des milieux potentiellement très toxiques et système de reproduction. Plus spécifiquement, je teste si la dépression de consanguinité dépend du niveau de stress que subissent les populations, en interaction avec l’histoire des pressions de sélection qu’on subies les populations par le passé. Enfin, à l’aide de simulations, j’étudie comment la variation interannuelle du système de reproduction peut influencer la probabilité d’adaptation de populations faisant face à un changement environnemental. / During my PhD, I focused on the evolution of mating system, adaptation and the mutual influences of both processes. I have been studying different aspects of this interaction using a hypertolerant, hyperaccumulator plant species, Noccaea caerulescens. This species grows on former mines and non-contaminated soils in Europe and in particularly in the Cévennes, and it is an excellent model to study the interaction of local adaptation in a heterogeneous environment and mating system. Firstly, I finely characterized N. caerulescens mating system in natural population, and see how metal pollution affects the variation of mating system in the Cévennes region. I showed that contrary to a couple of classical results (Antonovics 1968), in this system, metallicolous populations have lower self-fertilization rates than nonmetallicolous populations (article submitted). I then tested our best potential factor potentially explaining the variation of mating system in natural populations: plant density. In two different measures, with two different methods, density seems to have no or only a weak effect on self-fertilization rates in Noccaea caerulescens (article in prep). In a second project, I test the interaction between inbreeding depression, stress and the history of adaptation to a given environment using Noccaea caerulescens. Inbreeding depression is known to vary with environment and, sometimes, stress. Both experimental data (Long et al 2013) and theoretical models (Ronce et al 2009) stress the importance of the effect of the history of selection and adaptation in populations on the magnitude of inbreeding depression. Since we have populations of Noccaea caerulescens that are adapted to different levels of pollution, since different levels of pollution impose differential stress on the two ecotypes (strong polution is not good for nonmetallicolous plants) and since the species is self-compatible, this seems like an excellent system to test predictions on the interaction of inbreeding depression and mating system.

Nas últimas décadas tem se dado maior atenção à reprodução de animais silvestres, visto que para se conhecer e preservar uma espécie se faz necessário o conhecimento da história natural aliado aos processos da fisiologia e morfologia reprodutivas. Ciclos reprodutivos podem ser sazonais ou assazonais e apresentar variações em ambos os padrões. Por sua natureza e diversidade de fatores associados (e.g., atividade, dieta, temperatura), as estratégias reprodutivas vêm sendo investigadas sob uma abordagem evolutiva. Estudos do comportamento reprodutivo e dimorfismo sexual também têm sido destacados nesse âmbito. No entanto, poucos trabalhos são realizados para se conhecer as estratégias reprodutivas em serpentes neotropicais. Na maioria das vezes tais trabalhos abordam apenas alguns aspectos do ciclo reprodutivo de serpentes, como época de nascimentos, cópula e gestação, podendo ainda ser descritos de forma divergente pelo fato de muitos destes estudos serem norteados por dados de serpentes em cativeiro. Estudos microscópicos e macroscópicos, delineados com animais recém-chegados da natureza e preservados em coleções científicas, pode fornecer uma descrição e uma análise mais efetiva do ciclo reprodutivo permitindo a integração destes fatores. Assim, este trabalho investigou diversos aspectos da biologia reprodutiva de fêmeas e machos de populações de Bothrops alternatus do Brasil. Além disso, foram analisadas e descritas as estratégias reprodutivas empregadas por ambos os sexos durante o ciclo reprodutivo anual. Para isso, os espécimes foram dissecados ventralmente retirando-se fragmentos das gônadas e vias genitais de fêmeas e machos, em diferentes épocas do ano, a fim de se identificar as principais fases do ciclo vitelogênico, espermatogênico e do segmento sexual renal. Igualmente, para determinar se há estocagem de esperma nas fêmeas e nos machos, será investigada o útero aglandular e região do infundíbulo, vias genitais e ductos deferentes respectivamente. Tais dados permitirão compor um padrão reprodutivo, para essa espécie, levando-se em conta processos morfofisiológicos em ambos os sexos. Também foi realizada uma comparação dos ciclos reprodutivos entre populações de Bothrops alternatus e análises de possíveis influências ambientais na duração dos eventos reprodutivos / Over the last decades a greater attention has been given to the reproduction of wild animals, as the knowledge of natural history combined with the processes of reproductive physiology and morphology is essential for the preservation of a species. Reproductive cycles may be seasonal or not, and both patterns may have variations. Due to its nature and to the diversity of the associated factors (e.g., activity, diet, temperature), reproductive strategies have been investigated in an evolutionary approach. Studies of reproductive behavior and sexual dimorphism have also been highlighted in this context. However, few studies have been conducted to determine reproductive strategies in neotropical snakes. Most studies address only some aspects of the reproductive cycle of snakes, such as time of birth, copulation and pregnancy, and may present divergent descriptions as many of them are based on data from snakes in captivity. Microscopic and macroscopic studies carried out with animals newcomers from nature and preserved in scientific collections can provide a more effective analysis of the reproductive cycle allowing the integration of these factors. In this context, this project aims to investigate various aspects of the reproductive biology of female and male populations of Bothrops alternatus from Brazil. The reproductive strategies employed by both sexes during the annual reproductive cycle was analyzed and described. The specimens was dissected ventrally and fragments of gonads and genital tracts of females and males was removed at different times of the year in order to identify the main phases of the vitellogenic cycle, spermatogenesis and sexual segment of the kidney. Also, to determine whether sperm storage is done by females and males, we will investigate the aglandular uterus, the posterior infundibulum, genital tracts and vas deferens respectively. Such data was compose a reproductive pattern for the species that will take into account the morphophysiologic processes of both sexes. It was also performed a comparison of reproductive cycles between populations of Bothrops alternates and analysis of possible environmental influences in the duration of reproductive events

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No. of bitstreams: 2 Dissertação - Lorena Ferreira Peixoto - 2014.pdf: 2832669 bytes, checksum: ed2f415262daf1618ecdf785ad9bfb22 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2014-08-15 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Rice is a worldwide cultivated and consumed grain, playing an important role on the diet of half of the world’s population. Several losses in production and grain quality have been reported due to biotic factors, such as rice blast, caused by Magnaporthe oryzae, which is the major disease in rice crops. One of the most effective ways to control this disease is the use of resistant cultivars. However, the high genetic variability of the pathogen results in a rapid resistance loss. The discovery of highly fertile, hermaphrodites individuals outside of the rice center of origin, suggests that sexual reproduction may contribute to this genetic variability, which influences the appropriate control strategies. M. oryzae reproduction studies begins with the determination of mating types, controlled by two idiomorphic genes (MAT1-1 e MAT1-2), along with the sexuality (hermaphrodite, female or male) and fertility (number of perithecia). Another important approach under investigation for this crop is the detection of avirulence genes from M. oryzae, to understand the pathogen variability. Our study focused on the investigation of MAT1-1 or MAT1-2 genes, and the presence of the avirulence gene AVR1-CO39in field isolates collected from all rice production regions from Brazil. Sexuality and fertility were also characterized. 208 selected isolates were cultivated in PDA medium and the fungus mycelia were used for DNA extraction and PCR detection of the above-mentioned genes. For the sexual characterization, 106 field isolates were paired in Petri dishes containing rice bran medium with two reference isolates: KA-3 (MAT1-1) and GUY11 (MAT1-2), known worldwide for their mating type and high fertility. The AVR1-CO39 gene was only detected in two field isolates. One of them was able to infect the rice cultivar CO39, which has the resistance gene Pi-CO39(t). A mutation on AVR1-CO39 gene could impair the recognition of its effector by Pi-CO39(t) protein. Only one mating type (MAT1-2) was observed on the 208 field isolates. It was also observed that, among the 106 analyzed isolates, one (0,94%) was identified as a female; three (2,8%) as hermaphrodite, 62 (57,9%) as male; and 41 (38,3%) were not determined, considered infertile. We also observed the formation of perithecia inside of rice leaves. Despite the predominance of one mating type among rice field isolates, there is a possibility that sexual reproduction may occur as the other idiomorphic gene (MAT1-1) is present on field isolates collected from other Poaceae. The identification of highly fertile hermaphrodites and fertile-female individuals in this study also highlight this possibility. / O arroz é cultivado e consumido em todos os continentes, desempenhando um importante papel na dieta de mais da metade da população mundial. O seu cultivo vem sofrendo perdas na produção e na qualidade de grãos, devido a fatores bióticos como a brusone, causada pelo fungo Magnaporthe oryzae, que é a principal doença da cultura do arroz, representando uma ameaça à segurança alimentar mundial. O uso de cultivares resistentes é considerado o método mais efetivo para o controle da doença, porém, a alta variabilidade do patógeno resulta em uma rápida suplantação da resistência. Com a descoberta de isolados de alta fertilidade, hermafroditas, fora do centro de origem do arroz, sugere-se que a reprodução sexuada possa estar contribuindo para esta variabilidade genética, o que consequentemente influencia as estratégias apropriadas de controle. O estudo da reprodução sexuada em M. oryzae inicia-se com a definição dos tipos compatíveis, característica controlada pelo gene mating type com dois idiomorfos (MAT1-1 e MAT1-2); além das características como sexualidade (hermafrodita, fêmea ou macho) e fertilidade (número de peritécios). Outra abordagem de grande importância para a cultura é a detecção de genes de avirulência de M. oryzae, visando estudos de sua variabilidade. Dessa forma, o objetivo desta pesquisa foi investigar a presença dos genes MAT1-1 ou MAT1-2, e do gene de avirulência AVR1-CO39, em isolados coletados em todas as regiões produtoras de arroz do Brasil, além de caracterizá-los quanto à sexualidade e fertilidade. Foram selecionados 208 isolados que forma cultivados em BDA e seus micélios utilizados para extração de DNA e detecção dos genes citados. Para a caracterização sexual, 106 isolados de campo foram pareados em placa de Petri, contendo meio de farelo de arroz, com dois isolados: KA-3 (MAT1-1) e GUY11 (MAT1-2), os quais apresentam mating types e alta fertilidade, conhecidos mundialmente. O gene AVR1-CO39 foi detectado em apenas dois isolados, e um deles é patogênico à cultivar CO39, portadora do gene de resistência Pi-CO39(t), levantando a possibilidade de que uma mutação possa ter ocorrido, como deleção, o que impossibilita o reconhecimento do efetor pela proteína do gene Pi-CO39(t). Apenas um tipo compatível (MAT1-2) foi observado nos 208 isolados de campo. Foi observado também que, entre os 106 isolados analisados, um (0,94%), foi identificado como fêmea; três (2,8%), como hermafroditas; 62 (57,9%), como machos; e 41 (38,3%), como não determinados, sendo considerados inférteis. Observou-se também a formação de peritécios no interior da folha de arroz. Apesar do predomínio de um mating type, entre os isolados do arroz, há a possibilidade de ocorrência da reprodução sexuada, devido à presença do outro idiomorfo (MAT1-1) em isolados coletados de outras gramíneas, juntamente com a presença de hermafroditas e da fêmea-fértil, com alta fertilidade, de isolados MAT1-2 identificados nesse trabalho.

O pinhão manso é uma pequena árvore tropical que adquiriu importância econômica pelo conteúdo de óleo em suas sementes e pela possibilidade de sua utilização para produção de biocombustível. As sementes e o óleo do pinhão manso são tóxicos devido principalmente à presença de ésteres de forbol, o que dificulta a sua utilização direta para o consumo humano e também dos resíduos para a alimentação animal. A falta de programas de melhoramento e cultivares comerciais e problemas com pragas e doenças estão desestimulando o cultivo do pinhão manso pelo mundo. Por se tratar de uma espécie semi-domesticada, a utilização de marcadores moleculares como ITS, PCR-RFLP, microssatélites e TRAP poderia auxiliar nos estudos de diversidade genética, visando o desenvolvimento de variedades adaptadas às necessidades dos agricultores. O objetivo deste estudo foi caracterizar a variabilidade genética de acessos de pinhão manso depositados no Banco de Germoplasma da Universidade Federal de São Carlos, além de possibilitar estudos sobre as relações entre as populações, centros de diversidade e determinar o sistema reprodutivo da espécie. Os resultados são discutidos destacando que a maior parte da diversidade encontra-se entre as populações estudadas. Os resultados derivados dos quatro marcadores utilizados corroboram que o centro de diversidade da espécie possivelmente está na América, com destaque para o México, Brasil e Colômbia. Os resultados apontam também para a diferenciação genética dos acessos atóxicos dos mexicanos quando comparados com os demais acessos tóxicos de pinhão manso. Os marcadores microssatélites desenvolvidos indicam que o pinhão manso apresenta um sistema misto de reprodução, combinando autofecundações, apomixia e cruzamento entre indivíduos aparentados, o que pode explicar a menor diversidade genética encontrada dentro das populações. Devido ao sistema misto de reprodução e aos acasalamentos correlacionados, a coleta de sementes de polinização aberta para fins de melhoramento ou conservação deve ser conduzida em um número de árvores acima de 100, visando garantir uma amostra estruturada / Physic nut (Jatropha curcas L.) is a tropical tree that has acquired economic importance for the content of oil in its seeds and the possibility of its use for biofuel production. However, oil seeds and physic nut are toxic because of the presence of secondary metabolites such as phorbol esters which makes its use directly for human consumption and also its waste for animal feed difficult. The lack of commercial varieties and problems with pests and diseases are making physic nut cultivation in the world unattractive. The use of molecular markers such as ITS, PCR-RFLP, microsatellites and TRAP can help in studies of genetic diversity, aimed at developing varieties adapted to farmers needs. The aim of this study was to characterize the genetic variability of physic nut accessions deposited in the Germplasm Bank of the \'Universidade Federal de São Carlos\', in addition to allowing studies on the relationship among accessions, centers of diversity and reproductive system. Results are discussed highlighting that most diversity is concentrated among populations. The four markers used indicated that the center of diversity of this species is probably in America with emphasis on Mexico, Brazil and Colombia. The microsatellite markers indicate that physic nut has a mixed system of reproduction, combining self-pollinations, apomixis and crossing between related individuals which may explain the small genetic diversity found within populations. Due to the mixed system of reproduction and correlated mating, the collection of open-pollinated seeds for plant breeding or conservation should be conducted in a number of trees above 100 in order to ensure a structured sample

Pick-up lines are a "ritual that tries to turn strangers into lovers" (Murray, 1985, p.17). By studying how pick-up lines are perceived by the population, we might learn how the phenomenon of short- or long-term mating is initiated. By taking into account mating strategies, mate value, attractiveness, and flirting strategies, a pattern of behaviors and reactions may be observed. This study examines perceived pick-up line appropriateness and effectiveness when the attractiveness of the man delivering them varies. To test the effectiveness of 2 different types of pick-up lines, an online survey featuring 1 of 4 videos was administered. Results indicated that a humorous pick-up line was perceived as more effective and favorable than a slightly insulting one. An attractive man was perceived to be more communicatively competent than an unattractive man. Men, regardless of attractiveness, were perceived as more socially attractive when using a humorous pick-up line.

Unequal sex ratios are widespread in dioecious plants and understanding their cause is important to understanding fundamental aspects of their population dynamics, and yet what causes biased sex ratios in plants is still poorly understood. Competition experiments have been used in plants to predict the outcome of species interactions, but they have rarely been used to help explain sex ratio bias. This study used a response surface competition design to measure the relative competitive abilities of the sexes of the bryophyte Marchantia inflexa (a thallus liverwort of Marchantiaceae) to predict the outcome of competition before the onset of sexual reproductive structures. In bryophytes, dioecy and sex ratio bias is especially common, making them effective organisms for studying sex ratio bias. Given the frequency of female bias in bryophytes, the hypothesis was that females will show a higher competitive ability relative to males. The experiment was conducted in greenhouse conditions at several densities and proportions over the course of seven months. As individuals grew and formed clumps, identities were tracked, and growth measurements were made using photographs and computer imaging software. Both sexes grew on average 41% more with the opposite sex relative to their single-sex cultures. A model predicting future sex ratios showed coexistence between the sexes and predicted a male biased sex ratio of 3.2 males to 1 female. A trade-off was observed for males where single-sex cultures contained more asexual structures than mixed-sex cultures and the reverse for growth rate. Higher levels of asexual reproduction in males in single-sex cultures might be selected for to increase male dispersal for a higher probability of encountering females. This pattern was not found for females. The overyielding results suggest an interaction effect may exist due to niche differentiation between the sexes. In addition, the results suggest that in some dioecious plants a change in sex ratio can occur before differences in their allocation to sexual reproduction.

Selecting a mate is one of the most important and complex decisions that we make in our lives. Research on human decision making has found that we often use simple rules of thumb or heuristics to facilitate complex decision-making tasks (e.g., Gigerenzer & Todd, 1999; Kahneman & Tversky, 1972, 1973; Tversky & Kahneman, 1974, 1983). Recent research has focused on the use of affect or emotion as heuristics that have a strong influence on a variety of decision making contexts (Damasio, 1994; Finucane, Peters, & Slovic, 2003; Loewenstein, Weber, Hsee, & Welch, 2001; Mellers, 2000). The emotion we most closely associate with the context of choosing a mate is the emotion of love. The focus of this paper is on how love may serve as a heuristic to facilitate and guide our mate choice decisions. In order for falling in love to serve as an effective heuristic for making mate choice decisions, it should be triggered by characteristics that are adaptive from a mate satisfaction and evolutionary perspective. In Study 1, an attempt was made to ascertain the range of characteristics that people feel are most important to the experience of falling in love by asking participants to generate important partner characteristics for falling in love, casual sex, and marriage. In Study 2, the relative importance of the top characteristics was further refined using a Q-sort methodology. It was found that characteristics important to falling in love corresponded closely to those important for marriage. However, attractiveness and characteristics indicating that a person is enjoyable to be around, warm towards others, and an effective and honest communicator were seen as more important to falling in love than marriage. In Study 3, the role of falling in love as a simplifying heuristic for long-term mate choice decisions was assessed using a policy capturing approach. Results indicated that falling in love functions as a decision criterion only when partner characteristics are at their best levels. The implications of these findings for the role of falling in love as a heuristic for long-term mate choice decisions are discussed.

Sexual conflict over mating duration drives the evolution of male and female adaptations that facilitate the manipulation of mating interactions in their favor. This conflict drives the evolution of traits that improve the fitness of the focal sex despite inflicting costs on mates. However, males can express multiple traits that increase and decrease female fitness simultaneously. When the effects of male traits on female fitness increase or decrease with duration of exposure, females traits that influence mating duration are selected upon. Females of Callosobruchus maculatus, a bruchid bean beetle, kick mates to forcefully end copulation. Although both negative effects of male genital spines and positive of effects ejaculatory materials on female fitness have been documented, it is not yet clear how these male traits interact to influence the timing of female kicking. In this study, we observed the effect of male genital spine size, ejaculate size and mating history, and manipulated mating duration to disentangle the effects of male traits on the timing of female kicking behavior. We found that male mating history and mate body size dimorphism predicted the timing and duration of female kicking, but that male ejaculate size and spine length did not predict female kicking timing.

Swede midge (Contarinia nasturtii, Diptera: Cecidomyiidae) is a small invasive fly that is currently threatening Brassica vegetable and oilseed production in the Northeastern U.S. and Canada. Larvae feed on plant meristems, resulting in deformed leaves, stems, and heads. Extremely low damage thresholds for heading Brassica vegetables, multiple overlapping generations, and lack of effective organic insecticide options present serious challenges for managing this pest. Pheromone mating disruption (PMD), which involves confusing male insects with unnaturally large doses of sex pheromones, is particularly promising for swede midge management because it prevents mating and subsequent oviposition. One major challenge to PMD for swede midge management is that the chiral female pheromone blend, a 1:2:0.02 blend of (2S, 9S)-diacetoxyundecane, (2S, 10S)-diacetoxyundecane and (S)-2-acetoxyundecane, is expensive to synthesize due to the structural complexity of the compounds. Here, we explored three ways to reduce the cost of swede midge PMD: the use of lower-cost racemic pheromones containing all possible stereoisomers, single-component blends, and the possibility of using timed pheromone dispensers by testing for diel patterns of midge reproductive behavior. Although we found that males were not attracted to blends containing the racemic stereoisomers of the main pheromone component, (2S, 10S)-diacetoxyundecane, racemic blends functioned equally as well as chiral blends in confusing males and altering female behavior in PMD systems. We observed 95% and 87% reductions in males caught in monitoring traps in three-component chiral and racemic PMD plots of broccoli, respectively. In addition to confusing males, we also found that females altered their reproductive behavior in response to both chiral and racemic pheromones. Females released pheromones more frequently when exposed to three-component chiral and racemic blends, and were less likely to mate afterward. Single-pheromone treatments containing either chiral or racemic 2,10-diacetoxyundecane neither confused males nor influenced female behavior. We identified a total of eight hours during the day and night when midges do not exhibit mate-seeking behavior, during which programmable PMD dispensers could be turned off to save pheromone inputs. We found that up to 81% of females released pheromones to attract males for mating in the early morning shortly after dawn. Most females emerged in the morning as well, releasing pheromones soon after eclosing. Because midges are receptive to mates shortly after emergence, they may mate at their emergence site. Overall, we found relatively high levels of crop damage in our pheromone-treated plots, likely due to the migration of mated females into our plots. If midges mate at emergence sites, rotation of Brassica vegetable crops may result in overwintered midges emerging in fields where host plants are not currently grown. Further research is needed to determine where midges mate in order to determine where to install PMD dispensers.