Inscrit dans une approche croisant iconographie, anthropologie et histoire, ce travail porte sur les peintures de castes au Mexique au XVIIIe siècle. Ce genre – unique au sein de l’art colonial et plus largement occidental – narre le métissage entre Espagnols, Amérindiens et Africains en Amérique coloniale. Il s’agira ici d’étudier les représentations sociales et raciales engagées dans les œuvres, de dégager leurs logiques, tout en explorant leurs arrière-plans historiques et anthropologiques. Nous tenterons de démontrer que cette mise en image du métissage se nourrit d’un imaginaire aristocratique européen qui structure un rapport à l’animalité dont la famille consanguine est le parangon, mais également d’un mode de pensée indigène qui conçoit une certaine fluidité entre les ontologies humaine et animale. En même temps, nous mettrons en relief la manière dont ce genre pictural articule la classification spontanée du Nouveau Monde qui se donne libre cours aux prémices de la Colonisation et la classification savante caractéristique du Siècle des Lumières. Nées de l’interpénétration de ces différents cadres civilisationnels, les peintures de castes constituent un objet fondamentalement « métis ». / This study explores the paintings of castes in 18th century Mexico, combining iconography, anthropology and history. This type of painting, of a unique kind within colonial and even Western art, tells the story of the interbreeding between Spaniards, American Indians and Africans in colonial Central America. The research focuses on the social and racial representations that appear in the artistic productions and the logic that they reflect. The historical and anthropological background is also examined. We will attempt to show that the graphic presentation of miscegenation feeds on a European aristocratic fantasy that shapes a relationship to the animalistic nature symbolized by consanguineous family, and also on an indigenous pattern of thought that allows some fluidity between human and animal ontology. Moreover, we shall point out the way in which this pictorial genre expresses the spontaneous classification of the New World that flows freely during the premises of the colonization and the scientific classification specific to the Enlightenment. These caste paintings are the produces of two cultural surroundings and form an inherently cross-bred subject.

A utilização de variedades resistentes é uma importante ferramenta no manejo integrado de pragas e vem sendo valorizada nos programas de melhoramento de plaritas. Neste estudo foram avaliados 12 genátipas de milho, em relação aos danos causados por Spodoptera frugiperda (J.E. Smith, 179r7) em condições de campo, e em relação ao efeito desses genófípos na biologia da praga, em condições de laboratório. Os experimentos de campo foram realizados nos municípios de Casa Branca, Florínea e Miguetópotis/Guaíra, representando três diferentes regiões do Estado de São Pauto. As plantas foram avaliadas nas idades de 6 a 8 e de 10 a 12 folhas, através de uma escala de notas de O a 9. Os resultados da anáfíse de varíãncía mostraram que os danos causados pela lagarta-do-cartucho nos genótipos de milho foram diferentes nos três locais avaliados. A interação idade*local foi significativa, indicando que, dependendo do local avaliado, os danos foram diferentes em cada idade. Na idade de 6 a 8 folhas, os danos foram significativamente menores em Casa Branca em relação à Florínea e à Miguelápolis/Guaíra. Na idade de 10 a 12 folhas, os três locais apresentaram danos significativamente distintos. Miguelápolis/Guaíra foi o local que apresentou menos -úanos, em relação à r'lorínea. Casa Branca foi o local em que ocorreu mais danos. Na comparação das médias entre as idades em cada local, Casa Branca apresentou os menores danos na idade de 6 a 8 folhas, enquanto que, em Florinea e iviiguetópolis/Guaíra, isso ocorreu na idade de 10 a 12 folhas. Corri base na analise -úe agrupamento para os experimentos de campo, os genótipos Z 8486, C 333 B e Diria 766 formaram o grupo daqueles menos danificados, enquanto que os genótipos XL 212 e Piranão formaram o grupo dos mais danificados peia iagarta-do-cartucho. Houve pouco efeito dos genótipos avaliados sobre a biologia do inseto. Nos experimentos de laboratório, os genótipos Z 8486 e Master proporcionaram menor peso de lagartas aos 7 e 14 dias, em relação aos genótipo XL 212, enquanto em Z 8486 e IAC-Vitória ocorreu menor viabilidade larval em relação à Dina 766. O genótipo Dina 766, que ficou entre os menos danificados em condições de campo, proporcionou maior peso larval aos 7 dias e maior viabilidade larval. / Plant resistance is a usefui component of integrated pest management and its value has been increasing in plant breeding programs, ln this study, 12 maize genotypes were evaluated to damage of fali armyworm Spodoptera frugíperda (J.E. Smith, 1797) in field conditions. The effect of these genotypes on fali armyworm biology was evaluated in laboratory conditions. The field experiments were carried out in Casa Branca, Florínea and Miguelópolis/Guaíra, whích represent three different regions of São Paulo State. The plants were evaluated at 6-8 and 10-12 exposed leaves, using a rank scale from O to 9. The analysis of variance showed that the fali armyworm damage on maize genotypes differed in each of three places. The interaction age*piace was significant and it indicares that the damage differed according to the age of the plants, depending on where they were evaluated. At 6-8 leaf stage, the damage were less significant in Casa Branca comparing to Florínea and Miguetópolis/Guaíra. At 10-1 2 leaf stage, the three places showed damage with significant differences. Migueiópolis/Guaíra was the place with fewer damage, comparing to Florínea. ln Casa Branca occurred more damage. Comparing the age average of the plants in each region, the plants in Casa Branca showed fewer damage at 6-8 leaf stage whereas the plants in Florinea and Miguelópolis/Guaíra showed it at 10-12 leaf stage. ln the field experiments, the Cluster Analysis showed that Z 8486, C 333 B and Dina 766 genotypes set the group wíth fewer fali armyworm damage whereas XL 212 and Piranão genotypes set the most damaged group. The genotypes provided littie effect on fali armyworm biology. ln the laboratory experíments, the larvae reared on Z 8486 and Master genotypes provided lower weight on days 7 and 14, when compadng to XL 212. The genotypes Z 8486 and IAC-Vitória presented lower larval survival when comparing to Dina 766. The larvae reared on Dina 766 genotype provided the highest weight for day 7 and the greatest larval survival, even though, this genotype was one of the least damaged in the field.

Larvae of Pareuchaetes insulata were released in South Africa for the biological control of the invasive weed Chromolaena odorata. Pareuchaetes insulata has proved to be a difficult agent to establish in the field in South Africa, for various possible reasons. Populations collected from Florida and Jamaica (their aboriginal home) were released separately at several sites each in South Africa, but only one population (Florida) was definitely established. It is possible that adults from this established population interbred with adults from the Jamaican population released at nearby sites. The aims of this study were to determine whether there were any differences in biology between the two populations and whether hybridization affected the fitness of either. Trials involved: (i) pure-breeding of both Florida (F) and Jamaica (J) populations; (ii) cross-breeding of the two populations and; (iii) back-crossing of the hybrids with the parent populations. The fitness of these populations was determined by measuring adult longevity and fecundity, egg viability, and larval development and survival rates. The F population was superior to the J population in most of parameters measured, including fecundity. Hybridization of these populations reduced the fitness of the F population. It is unknown whether these differences in fitness reflect differences in their native regions, laboratory cultures or response to South African C. odorata. It appears that different populations of P. insulata have different levels of fitness, and that hybridization negatively affects the fitness of stronger populations. The lower fitness of the J population may have reduced its likelihood of establishing successfully, and even reduced the fitness of the established F population where the populations came into contact. These results caution that the possible consequences of mixing different genotypes of a biocontrol agent species should be properly investigated prior to their release in the same country. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

A utilização de variedades resistentes é uma importante ferramenta no manejo integrado de pragas e vem sendo valorizada nos programas de melhoramento de plaritas. Neste estudo foram avaliados 12 genátipas de milho, em relação aos danos causados por Spodoptera frugiperda (J.E. Smith, 179r7) em condições de campo, e em relação ao efeito desses genófípos na biologia da praga, em condições de laboratório. Os experimentos de campo foram realizados nos municípios de Casa Branca, Florínea e Miguetópotis/Guaíra, representando três diferentes regiões do Estado de São Pauto. As plantas foram avaliadas nas idades de 6 a 8 e de 10 a 12 folhas, através de uma escala de notas de O a 9. Os resultados da anáfíse de varíãncía mostraram que os danos causados pela lagarta-do-cartucho nos genótipos de milho foram diferentes nos três locais avaliados. A interação idade*local foi significativa, indicando que, dependendo do local avaliado, os danos foram diferentes em cada idade. Na idade de 6 a 8 folhas, os danos foram significativamente menores em Casa Branca em relação à Florínea e à Miguelápolis/Guaíra. Na idade de 10 a 12 folhas, os três locais apresentaram danos significativamente distintos. Miguelápolis/Guaíra foi o local que apresentou menos -úanos, em relação à r'lorínea. Casa Branca foi o local em que ocorreu mais danos. Na comparação das médias entre as idades em cada local, Casa Branca apresentou os menores danos na idade de 6 a 8 folhas, enquanto que, em Florinea e iviiguetópolis/Guaíra, isso ocorreu na idade de 10 a 12 folhas. Corri base na analise -úe agrupamento para os experimentos de campo, os genótipos Z 8486, C 333 B e Diria 766 formaram o grupo daqueles menos danificados, enquanto que os genótipos XL 212 e Piranão formaram o grupo dos mais danificados peia iagarta-do-cartucho. Houve pouco efeito dos genótipos avaliados sobre a biologia do inseto. Nos experimentos de laboratório, os genótipos Z 8486 e Master proporcionaram menor peso de lagartas aos 7 e 14 dias, em relação aos genótipo XL 212, enquanto em Z 8486 e IAC-Vitória ocorreu menor viabilidade larval em relação à Dina 766. O genótipo Dina 766, que ficou entre os menos danificados em condições de campo, proporcionou maior peso larval aos 7 dias e maior viabilidade larval. / Plant resistance is a usefui component of integrated pest management and its value has been increasing in plant breeding programs, ln this study, 12 maize genotypes were evaluated to damage of fali armyworm Spodoptera frugíperda (J.E. Smith, 1797) in field conditions. The effect of these genotypes on fali armyworm biology was evaluated in laboratory conditions. The field experiments were carried out in Casa Branca, Florínea and Miguelópolis/Guaíra, whích represent three different regions of São Paulo State. The plants were evaluated at 6-8 and 10-12 exposed leaves, using a rank scale from O to 9. The analysis of variance showed that the fali armyworm damage on maize genotypes differed in each of three places. The interaction age*piace was significant and it indicares that the damage differed according to the age of the plants, depending on where they were evaluated. At 6-8 leaf stage, the damage were less significant in Casa Branca comparing to Florínea and Miguetópolis/Guaíra. At 10-1 2 leaf stage, the three places showed damage with significant differences. Migueiópolis/Guaíra was the place with fewer damage, comparing to Florínea. ln Casa Branca occurred more damage. Comparing the age average of the plants in each region, the plants in Casa Branca showed fewer damage at 6-8 leaf stage whereas the plants in Florinea and Miguelópolis/Guaíra showed it at 10-12 leaf stage. ln the field experiments, the Cluster Analysis showed that Z 8486, C 333 B and Dina 766 genotypes set the group wíth fewer fali armyworm damage whereas XL 212 and Piranão genotypes set the most damaged group. The genotypes provided littie effect on fali armyworm biology. ln the laboratory experíments, the larvae reared on Z 8486 and Master genotypes provided lower weight on days 7 and 14, when compadng to XL 212. The genotypes Z 8486 and IAC-Vitória presented lower larval survival when comparing to Dina 766. The larvae reared on Dina 766 genotype provided the highest weight for day 7 and the greatest larval survival, even though, this genotype was one of the least damaged in the field.