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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Economie végétale et pratiques agricoles au Bronze final et au premier âge du Fer, de la côte de l'Île-de-France à la côte de Champagne / Vegetal economy and agricultural practices during late Bronze age and early Iron age, between Île-de-France cuesta and Champagne cuesta

Ferrage, Françoise 01 July 2013 (has links)
Les âges du Bronze final et du premier Fer constituent, pour la Champagne, une phase d'expansion des installations humaines. C'est également au Bronze final que se généralise, à l'échelle européenne, l'adoption de nouvelles plantes cultivées, les millets, l'épeautre, l'ers, la féverole et la caméline. L'étude carpologique de 21 sites localisés dans la Plaine de Troyes, le Pays remois et la Bassée, livre des informations sur l'agriculture qui accompagne cette expansion, et sur la façon dont elle intègre les changements observés à l'échelle européenne. Dès le début du Bronze final, une agriculture diversifiée est en place. Elle inclue les nouvelles plantes, qui prennent une part importante aux productions régionales basées sur l'orge vêtue, le millet commun, et les blés vêtus, dont l'épeautre et le «new» glume wheat, blé jusqu'alors inconnu en France. La lentille, l'ers et la caméline jouent un rôle notable, complémentaire à celui des céréales. L'agriculture est stable pendant les 9 siècles étudiés. Les parcelles sont cultivées de manière permanente et plutôt intensive, sans baisse de la fertilité des sols. Une expansion des espaces pâturés est probable au cours du premier âge du Fer, peut-être sous forme de jachères. Les systèmes de culture semblent capables de répondre aux besoins de subsistance et de se perpétuer. Des pratiques sociales de repas collectifs sont attestées. Les différences qui existent entre les productions végétales, selon les secteurs géographiques, peuvent être liées aux contraintes du milieu, ou à certaines affinités culturelles. / Late Bronze Age and Early Iron Age are for the Champagne area an expansion phase of human facilities. It is also during Late Bronze age that generalizes, at European level, adoption of new crops, millets, spelt, bitter vetch, field bean and gold of pleasure.The archaeobotanical study of 21 sites located in the plain of Troyes, the area of Reims and the Upper Seine Valley provides information on agriculture, which accompanies this expansion, and how it incorporates the changes observed in Europe. From the beginning of Late Bronze Age, diversified agriculture is in place. It includes the new plants, which take an important part in regional productions based on hulled barley, broomcorn millet, hulled wheats, including spelt and the "new" glume wheat, previously unknown in France. Lens, bitter vetch and go Id of pleasure play a significant role, complementary to that of cereals. Agriculture is stable during the 9 centuries investigated. Plots are cultivated permanently and rather intensively, without loss of soil fertility. An expansion of pasture areas is likely during early Iron Age, perhaps as fallows. Ability to produce surpluses seems low, but production systems are able to meet subsistence needs, and perpetuate. Mobilizing surplus in social practices of collective feasting is also likely. Crops show differences between geographical areas, in part related to the characteristics of the environment, but perhaps also due to some cultural affinities.
42

La flore de l'interface route - champ cultivé : Influence des pratiques de gestion de la structure du paysage / The road-field boundary's vegetation : effect of management practices and landscape structure

Chaudron, Clémence 14 December 2016 (has links)
Les bords de route constituent un des principaux habitats herbacés et linéaires des paysages agricoles, ils jouent le rôle de refuge pour différentes espèces et constituent aussi un habitat favorable pour des espèces adventices jugées problématiques. L’objectif de cette thèse est de mesurer les effets de la structure du paysage et des pratiques de gestion sur la flore de l’interface route – champ cultivé. Nos résultats suggèrent que les communautés végétales de l’interface ont une réponse temporellement décalée vis-à-vis des changements paysagers. L’étude de la végétation exprimée et de la dispersion des graines montre que la fauche tardive n’est pas le levier de gestion optimal pour favoriser la diversité végétale du bord de route, et que les pratiques de fauche influencent aussi la flore de la bordure intérieure du champ. Afin de limiter les influences croisées des pratiques de gestion, nous suggérons des stratégies réfléchies à l’échelle de l’interface route – champ. / Road verges constitute the main herbaceous and linear habitats of arable landscapes. They represent a refuge for different species, but also constitute a habitat for weeds considered problematic. The aim of this thesis was to measure the effects of landscape structure and management practices on the flora of the road-field boundary. Our results suggest that plant communities of road-field boundary have a time lagged response to landscape changes. The study of the vegetation and of seed dispersal showed that late mowing was not the optimal method to promote plant diversity on road verges and that mowing practices also influenced the flora of the inner field margin. To limit the cross-influence of management practices, we recommend well thought out strategies at the scale of the road-field boundary.
43

Pr?ticas agroecol?gicas para o cultivo do gergelim (Sesamum indicum L.) / Agroecological practices for the sesame (Sesamum indicum L.) cultivation

Ara?jo, Afr?nio C?sar de 24 February 2014 (has links)
Made available in DSpace on 2015-03-12T11:55:52Z (GMT). No. of bitstreams: 1 AfranioCA_TESE.pdf: 5802290 bytes, checksum: fd6a3b6955fd8eca343b02a54254a104 (MD5) Previous issue date: 2014-02-24 / The exceeded use of the natural resources required by the modern agriculture has been caused soil impoverishment, soil salinization and soil compaction. The unreasonable use of chemical fertilizers and pesticides causes chemical imbalances in the plant tissues, nutritional losses, taste chances and human health problems. The monocrops are more vulnerable to the pest and disease attacks. The aim of this work were to indicate the better relative planting time of the cowpea bean for the sesame/cowpea bean intercropping based on the evaluation of agronomic, economic, ecological and physiological parameters and to evaluate the viability of the cow urine and cassava wastewater use as alternative fertilizers on the sesame cultivation. In a field essay, when the sesame/cowpea bean was evaluate, the mainly treatments were the single planting of the two cultures and the multiple cropping, with the cowpea bean being planted on the same time, 7, 14 and 21 days after the sesame. The mainly treatments of the second essay were the combined doses of the cow urine (0 and 50 ml) and cassava wastewater (0, 500 and 1000 mL). In the intercrop evaluation significant differences were found between the treatments for the most of the parameters. It was verified that as the sowing of the cowpea bean was retarded in relation to the sesame sowing, the sesame performance increased when the cowpea bean performance decreased. The treatment 7 days balanced the competition relations that occurred between the two crops in the intercrop. The sesame presented little pronounced responses to the different doses of cassava wastewater. The cow urine affected the sesame growth and the growth rates increased with the increasing of the application of the product. The responses of the sesame growth to the cow urine application must be related both the nutritional richness of the product and the presence of growth stimulating substances. The obtained results indicated that in the sesame/cowpea bean intercropping, when the sesame is planted 7 days after the sesame, there is a higher possibility of the net gains to the farmer. Cow urine and cassava wastewater may be used as additional organic fertilizers / A explora??o exacerbada dos recursos demandados pela Agricultura Moderna vem provocando empobrecimento, saliniza??o e compacta??o dos solos. O uso irracional de fertilizantes qu?micos e agrot?xicos tem causado desequil?brio qu?mico nos tecidos vegetais, perdas nutricionais, altera??es no sabor e problemas na sa?de humana. As monoculturas est?o mais sujeitas ao ataque de pragas e doen?as, sendo altamente dependentes de agrot?xicos. Objetivou-se, com este trabalho: (1) indicar a(s) ?poca(s) relativa(s) mais apropriada(s) de plantio do feij?o caupi no cons?rcio com o gergelim a partir da avalia??o de aspectos agron?micos, econ?micos, ecol?gicos e fisiol?gicos e (2) avaliar a viabilidade da utiliza??o de urina de vaca e manipueira como fertilizantes alternativos no cultivo do gergelim. No ensaio de campo, quando o cons?rcio gergelim/feij?o caupi foi avaliado, os tratamentos principais foram os monocultivos das duas culturas e os cultivos consorciados, sendo a Fabacea plantada no mesmo tempo, 7, 14 e 21 dias ap?s a Pedaliaceae. No experimento em vasos, os tratamentos principais constaram de doses combinadas de urina de vaca (0 e 50 mL) e manipueira (0, 500 e 1000 mL). Na avalia??o do cons?rcio, foram verificadas diferen?as significativas entre os tratamentos para a maior parte das vari?veis. Percebeu-se que na medida em que se atrasava a semeadura do feij?o caupi em rela??o ao plantio do gergelim, obtinham-se respostas proporcionalmente mais positivas para a Pedaliaceae, o contr?rio ocorrendo para o feij?o. Destacou-se o tratamento 7 dias como o ponto de equil?brio considerando as rela??es competitivas estabelecidas entre as duas culturas no cons?rcio. O gergelim apresentou respostas pouco pronunciadas ?s diferentes doses isoladas de manipueira. A urina de vaca exerceu efeito sobre o crescimento vegetativo do gergelim, o que se refletiu no aumento das taxas de crescimento em resposta ? aplica??o do produto. As respostas do crescimento do gergelim ? aplica??o da urina de vaca devem estar relacionadas tanto ? riqueza nutricional do produto quanto ? presen?a de subst?ncias estimuladoras do crescimento. Os resultados encontrados sugerem que, no cons?rcio gergelim/feij?o caupi, quando a Fabacea ? plantada 7 dias ap?s o gergelim, h? maior possibilidade de ganhos l?quidos para o produtor e que urina de vaca e manipueira podem ser utilizados como complementos na aduba??o do gergelim
44

Fatores de influ?ncia na produ??o de leite bovino sobre os n?veis da contagem bacteriana total / Factors influencing the production of bovine milk on the levels of total bacterial count

Guerra, Mirela Gurgel 07 February 2012 (has links)
Made available in DSpace on 2014-12-17T15:34:45Z (GMT). No. of bitstreams: 1 MirelaGG_DISSERT.pdf: 523258 bytes, checksum: b38fc504491b6e5e1a948b5fb7c8a832 (MD5) Previous issue date: 2012-02-07 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The objective of this study was to evaluate the influence of milking procedures on the levels of total bacterial count (TBC) in bovine milk. In the first study the influences of procedures for hygienic milking, cleaning of milking equipment and milk cooling tanks on the TBC levels were evaluated. Four bulk samples of milk were collected from each tank in eight properties for TBC analysis, employing the flow cytometry method. A questionnaire was applied in each property to assess the current situation of milking procedures on each production system that took part on this research, followed by training of employees in good agricultural practices in the production of milk and monitoring of the TBC measurements. The methodology for analysis of longitudinal data was considered, focusing on random effects models. The results showed that the handling procedures for milking and the cleanliness of the cooling tank contributed to a further reduction in the levels of TBC raw milk cooling tanks. The second study aimed to describe the percentage of the properties that comply with the Normative Instruction N? 51 (Brazil s IN 51) with regard to total bacterial count (TBC) in bovine milk. The study was conducted from January 2010 to July 2011. Milk samples were collected from the eight properties selected for TBC analysis by the flow cytometry method. Again, on each property a questionnaire was applied to assess the current situation of milking procedures on each production system that took part on this research, followed by training of employees in good agricultural practices in the production of milk and monitoring of the TBC measurements. The methodology of marginal models based on Generalized Estimate Equations (GEEs) was followed in the statistical analysis. The results showed that the handling procedures of the milking and the cleanliness of the cooling tanks contributed to a considerable percentage of the properties that reached the limits of TBC established by IN 51 / Objetivou-se com este trabalho avaliar a influ?ncia dos procedimentos de ordenha sobre os n?veis da Contagem Bacteriana Total (CBT) no leite bovino. No primeiro estudo foram avaliados as influ?ncias dos procedimentos de ordenha higi?nica e de limpeza dos equipamentos de ordenha e dos tanques de resfriamento do leite sobre os n?veis da CBT. Para tanto, foram coletadas quatro amostras de leite de cada tanque de oito propriedades, para an?lise da CBT, pela metodologia de citometria de fluxo. Em cada propriedade aplicou-se um question?rio para avalia??o da atual situa??o dos procedimentos de ordenha em cada sistema de produ??o participante da pesquisa, seguida da capacita??o e treinamento dos colaboradores em boas pr?ticas agropecu?rias na produ??o de leite e uma fase de acompanhamento das medidas da CBT. Considerouse a metodologia para an?lise de dados longitudinais, com enfoque nos modelos de efeitos aleat?rios. Observou-se que os procedimentos adequados no manejo na ordenha e na limpeza do tanque de resfriamento contribu?ram para uma maior redu??o nos n?veis da CBT do leite cru de tanques de resfriamento. No segundo estudo, objetivou-se descrever a propor??o de propriedades que atendem ? Instru??o Normativa n? 51 (IN 51) em rela??o ? Contagem Bacteriana Total (CBT) em leite bovino. O estudo foi realizado no per?odo de janeiro de 2010 a julho de 2011. Foram coletadas amostras de leite de oito propriedades selecionadas, para an?lise da CBT pelo m?todo de citometria de fluxo. Em cada propriedade aplicou-se um question?rio para avalia??o da atual situa??o dos procedimentos de ordenha em cada sistema de produ??o participante da pesquisa, seguido da capacita??o e treinamento dos colaboradores em boas pr?ticas agropecu?rias na produ??o de leite e uma fase de acompanhamento das medidas da CBT. Para an?lise estat?stica considerou-se a metodologia para modelos marginais baseada nas Equa??es de Estima??es Generalizadas (EEGs). Constatou-se que os procedimentos adequados no manejo da ordenha e na limpeza do tanque de resfriamento contribu?ram para que uma parcela consider?vel das propriedades atingisse os limites da CBT estabelecidos pela IN 51
45

Analyse des conflits et synergies entre services écosystémiques multiples en vergers de pommiers / Analyzing multiple ecosystem services in apple orchards

Demestihas, Constance 23 February 2017 (has links)
Le concept de « service écosystémique », en plein essor depuis la publication du Millenium Ecosystem Assessment en 2005, a permis de souligner l'importance des performances non-marchandes des écosystèmes. En arboriculture, assurer une bonne productivité tout en préservant les ressources naturelles et la santé humaine est aujourd’hui un défi majeur, qui peut être analysé sous l’angle des services écosystémiques. Quels sont ces services au sein d’un verger de pommiers ? Comment les analyser ? Quels sont les liens - conflits et synergies - entre services écosystémiques multiples et comment les systèmes de culture modifient-ils les profils de services multiples? Ce travail de thèse vise à répondre à ces questions avec une démarche novatrice combinant mesures expérimentales, modélisation et analyse statistique. Suite à une analyse bibliographique des services écosystémiques pouvant être délivrés dans des vergers, cinq services ont été sélectionnés. Il s’agit de la production de fruits, de la disponibilité de l’azote dans le sol, de la régulation du climat reposant sur la prévention de la dénitrification de l’azote et sur la séquestration du carbone, de la maintenance et de la régulation du cycle de l’eau y compris de sa qualité, et de la régulation des bioagresseurs. Conjointement à ces services nous avons considéré les nuisances environnementales dues aux pesticides. Pour chaque service nous avons identifié les fonctions écosystémiques sous-jacentes ainsi que les pratiques agricoles et les conditions pédoclimatiques ayant un impact sur ces fonctions. Les services et fonctions ont été décrits par un ou plusieurs indicateurs et quantifiés à l’aide de modèles dans les cas suivants : (i) neuf systèmes de culture réels sur deux dispositifs expérimentaux dans le sud-est de la France et (ii) 150 systèmes de culture fictifs conçus à partir de la combinaison de cinq leviers de pratiques et de leurs modalités, dans des conditions pédoclimatiques identiques. Les deux modèles utilisés ont été STICS, un modèle générique de simulation du fonctionnement du sol et des cultures sous l’influence des pratiques, qui a nécessité une paramétrisation et une évaluation sur pommier à partir de mesures expérimentales, et IPSIM, une plateforme de modélisation simulant les effets des pratiques et des conditions du milieu sur les dégâts aux cultures causés par les bioagresseurs. IPSIM a été paramétré sur pommier, sur la base d’une importante étude bibliographique et à dires d’experts. Les simulations des modèles ont fait l’objet d’analyses statistiques simples dans le cas des systèmes de culture réels, et d’analyses multivariées à deux tableaux (analyse en composantes principales avec variables instrumentales) pour les systèmes de culture fictifs. Pour les neufs systèmes de culture réels, 14 liens importants entre services écosystémiques ont été identifiés, notamment des conflits comme celui entre la prévention de la dénitrification ou de la lixiviation de l’azote et la disponibilité de l’azote dans le sol à court terme, et des synergies, comme celle entre l’humidité du sol ou la séquestration du carbone et la disponibilité de l’azote dans le sol à court terme. Ces liens entre services sont expliqués par les fonctions écosystémiques sous-jacentes. La comparaison de profils de services entre systèmes a mis en évidence l’impact de pratiques agricoles sur certains services. Ainsi, sur un même site, une forte densité de plantation augmente la production de fruits et la séquestration du carbone. La fertilisation exclusivement sous une forme organique diminue la production de fruits via un stress azoté mais diminue également la lixiviation. Par ailleurs, les profils de services sont fortement influencés par les caractéristiques pédoclimatiques de chaque site. Ces résultats confortent la nécessité d’une prise en compte explicite de l’interdépendance ‘pratiques x conditions du milieu’ pour analyser les services. / The concept of « ecosystem service », which has been used increasingly since the publication of the Millennium Ecosystem Assessment in 2005, has highlighted the importance of ecosystem’s non-marketed performances. In orchards, ensuring high productivity while preserving natural resources and human health has become a real challenge that could be analyzed with the concept of ecosystem service. Which ecosystem services are delivered in an apple orchard? How to analyze them? What are the relationships - conflicts or synergies – among multiple ecosystem services and how do cropping systems change multiple ecosystem service profiles? This PhD work aims at answering those questions with an innovative approach combining experimental measures, modeling and statistical analysis.Based on a literature review of ecosystem services in orchards, five services were selected: fruit production, nitrogen availability in soil, climate regulation based on the prevention of nitrogen denitrification and on carbon sequestration, maintenance and regulation of water cycle, including water quality, and pest control. We also considered the environmental disturbances caused by the use of pesticides. For each service, we identified the underlying ecosystem functions as well as the agricultural practices and soil and climate conditions affecting these functions. Services and functions were described by one or multiple indicators and quantified using models in the case of (i) nine existing cropping systems on two experimental sites in southeastern France differing in terms of soil and climate conditions, and (ii) 150 virtual cropping systems designed out of the combination of five major agricultural practice levers and their modalities, in identical soil and climate conditions. The two models used were STICS, a generic soil-crop simulation model under the influence of practices which required a parameterization and an evaluation on apple orchards based on experimental measures, and IPSIM, a generic modeling framework simulating the impacts of agricultural practices and local conditions on crop injuries caused by pests. IPSIM was parameterized on apple orchards, based on an important literature review and expert opinions. Model simulations were analyzed with simple statistics in the case of the nine existing cropping systems and with two-table multivariate analyses (principal component analysis with instrumental variables) for virtual cropping systems.Concerning the existing cropping systems, 14 important relationships were identified among ecosystem services, especially conflicts, like the one between nitrogen denitrification or leaching prevention and soil nitrogen availability on the short term, and synergies such as the one between soil humidity or carbon sequestration and nitrogen availability on the short term. These relationships are explained by the underlying ecosystem functions. Comparing service profiles among cropping systems highlighted the impacts of agricultural practices on some services. That way, on a same site, a high planting density increases fruit production and carbon sequestration. An exclusively organic fertilization decreases fruit production through nitrogen stress but also nitrogen leaching in drained water. Furthermore, service profiles are strongly influenced by the soil and climate conditions of each site. These results strengthen the need to explicitly consider the ‘agricultural practices x soil and climate conditions’ interdependence in order to analyze ecosystem services. The results obtained with the virtual cropping systems simulations confirmed those of the existing ones and gave precision on the impacts of fertilization, irrigation and pest control for codling moth, rosy apple aphid and apple scab on ecosystem functions and services.
46

Abondance et origine trophique de la noctuelle de la tomate (Helicoverpa armigera) dans les paysages ruraux de production cotonnière au Nord Bénin / Abundance and trophic origin of the Cotton Bollworm (Helicoverpa armigera) in cotton producing farmland of North Benin

Tsafack-Menessong, Noëlline 10 July 2014 (has links)
Mettre en place des stratégies de lutte contre les ravageurs, indépendantes des produits chimiques est un objectif fondamental pour une protection durable des cultures contre les ravageurs et la conservation d’un environnement sain pour les populations humaines en zone rurale. L’objectif principal de ce travail était de contribuer à la mise en place d’une lutte biologique par gestion des habitats à l’échelle du paysage de la noctuelle polyphage Helicoverpa armigera, principal ravageur de cotonnier dans le nord Bénin. Cette thèse visait à analyser l’influence des pratiques agricoles et de l’organisation du paysage sur l’abondance et l’origine trophique de H. armigera. L’analyse biochimique d’individus élevés en laboratoire, nous a permis de confirmer le fait que le gossypol est un bon marqueur pour identifier les adultes qui ont passé leur vie larvaire sur le cotonnier. Au contraire de la tomatine qui ne peut être considérée comme un marqueur de la tomate car la tomatine a été détectée seulement chez les larves d’H. armigera et non chez les adultes. Notre étude sur le terrain au nord Bénin dans 40 parcelles, a montré que les pratiques agricoles avaient un fort effet sur l’infestation larvaire. La date de semis et la fréquence de sarclage étaient négativement corrélées à l’infestation larvaire. La proportion de cotonniers dans le paysage et celle de tomate ont influencé positivement l’infestation en larves d’H. armigera. Nous avons également montré qu’un précédent cultural tomate présentait une abondance larvaire en moyenne trois fois supérieur à un précédent cultural maïs. Ensuite, dans des rayons de 100 m, 250 m et 500 m, nous avons étudié les effets de la composition et de l’hétérogénéité du paysage d’une part sur l’abondance des adultes d’H. armigera et d’autre part sur leur origine trophique. L’hétérogénéité du paysage en plantes hôtes est le facteur paysager principal qui a influencé positivement l’abondance des adultes. Les isotopes stables de Carbone nous ont permis d’identifier les individus dont la larve s’était nourrie sur des plantes de type photosynthétique C3 (cotonniers, tomates, ...) ou C4 (maïs, sorgho, …). L’origine trophique, plantes hôtes C3 ou C4, est reliée positivement à la proportion de plantes hôtes respectivement C3 ou C4 dans un rayon de 500m. Seulement 10% des individus ayant consommés des plantes en C3 ont été détecté positif au gossypol. La proportion de cotonniers dans le paysage ne semble pas expliquer la proportion d’individus détectés positif au gossypol. Nous formulons des propositions de gestion de l’assolement et des rotations culturales pour contribuer à la régulation d’H. armigera. Ainsi, il faudrait éviter que le cotonnier soit semé sur un précédent cultural tomate. Il serait important de décaler les dates de semis entre les parcelles de cotonniers voisines et de respecter la fréquence de sarclage minimale qui est de trois. Par ailleurs, il serait judicieux de préférer un environnement paysager homogène autour d’une parcelle de cotonnier, en privilégiant par exemple, le maïs. / The development of strategies independent of pesticides is a fundamental objective for sustainable crop protection against pests as well as for maintaining of a healthy environment for human populations. The rationale of the research presented here was to improve our ability to control the cotton bollworm, Helicoverpa armigera by non-pesticide methods via habitat conservation. We analyzed the influence of agricultural practices and landscape composition and diversity on the abundance and trophic origin of H. armigera and assessed gossypol and tomatine in individual H. armigera as cotton and tomato biomarkers respectively. Gossypol was shown to be a stable cotton biomarker, even in adult H. armigera 12 days after emergence. In contrast, tomatine was only detected in larvae of H. armigera and not adults; thereby tomatine can not be considered as a marker of tomato plants. Subsequently, in north Benin, the abundance of H. armigera larvae and adults was monitored in cotton fields. We found a strong effect of agricultural practices on H. armigera larvae abundance. Delay sowing date and increase frequency of weeding reduced the abundance of H. armigera in cotton fields; whereas the proportion of cotton and tomato in the landscape increased. This study also highlights the role of the previous landcover in the infestation of a cotton field: A previous tomato landcover increased infestation three times more than a previous maize landcover. At nested scales ranging from 100 m, 250 m to 500 m, we studied the effects of landscape composition and diversity firstly on the abundance of adult H. armigera and secondly on their trophic origin. We found that, landscape diversity was the main factor that influenced both the abundance adult and their trophic origin at 500 m scale. Analyses of stables isotopes of Carbone showed that proportion of hosts plants with C3 photosynthetic pathway in the landscape was positively related to H. armigera moths with C3 trophic origin signal at 500 m scale. Only 10% of moths were positive to gossypol signal. The proportion of cotton in the landscape seems not important to explain the trophic origin of individual which were positive to gossypol signal. Therefore, for integrated management of H. armigera our results suggest it is necessary to consider the following agricultural practices and crop diversity regimes (in regard to the resource use strategies of this polyphagous pest). A tomato previous landcover should be avoid; shift sowing date between cotton fields, and have at less three manual weedings. In additional, we suggest employing maize around cotton fields rather than other crops.
47

Propuesta de mejora de productividad basado en un Sistema Básico de Gestión por Procesos en las Mypes productoras de granada en el distrito de Santiago en Ica / Proposal to improve productivity based on a Basic Process Management System in the SMEs pomegranate producers in the district of Santiago in Ica

Cervantes Rivera, Hans Macálisther, Chicle Minchola, Gonzalo Octavio 10 December 2020 (has links)
El presente proyecto está enfocado en analizar el proceso de producción de la granada. Todas las actividades físicas, que intervienen dentro del proceso productivo, determinarán los niveles de producción que se originan en cada campaña. Estas cualidades presentan una gran importancia para elevar el valor del producto dentro de los distintos mercados de exportación, como Holanda, Francia, Ucrania; a los que apuntan los productores de Santiago-Ica. Se ha identificado que el sector agrícola representa la mayor proporción dentro de los ingresos económicos que percibe el país en temas de exportación. Dentro de este mismo sector, se ha percibido que la Granada ha experimentado un constante crecimiento en sus niveles de exportación debido a que la demanda de esta fruta se ha incrementado considerablemente en países europeos y asiáticos. La presente investigación se enfoca a satisfacer las grandes demandas de otros países, incrementando las capacidades de producción en las MYPES. Se han realizado evaluaciones del proceso de producción actual que se ejecutan en esta zona geográfica tomando como referencia las buenas prácticas agrícolas que son usadas en otros países con mejores indicadores de productividad. Este análisis ha permitido obtener diferencias significativas entre ambos procesos; es por ello que se ha elaborado un modelo propuesto, que será implementado usando herramientas básicas de la gestión por procesos para estandarizar las actividades a realizar y obtener resultados mejor estructurados que estén alineados a incrementar los niveles de producción y la optimización en el uso de los recursos. Los resultados obtenidos serán analizados y usados para la generación de indicadores, las cuales han sido seleccionadas con la técnica SMART, que nos permitan comparar la productividad obtenida de un mismo pedazo de terreno antes y después de la propuesta de mejora. ​Finalmente, el modelo propuesto será consultado y validado usando la técnica de juicio de expertos para lo cual consultamos con usuarios de las MYPES del sector y con expertos en el manejo de herramientas de gestión por procesos. Estos resultados serán analizados usando la matriz PUGH como herramienta para cuantificar la aprobación de cada uno de los expertos. / This project is focused on analyzing the pomegranate production process. All the physical activities that intervene in the production process will determine the levels of production that originate in each campaign. These qualities are of great importance to raise the value of the product within the different export markets, such as Holland, France, Ukraine; to which the producers of Santiago-Ica are targeting. It has been identified that the agricultural sector represents the largest proportion within the economic income that the country receives in export issues. Within this same sector, it has been perceived that Granada has experienced a constant growth in its export levels due to the fact that its demand has increased considerably in European and Asian countries. This research is focused on satisfying the great demands of other countries, increasing the production capacities in SMEs. Evaluations of the current production process that are carried out in this geographical area have been carried out, taking as a reference the good agricultural practices that are used in other countries with better productivity indicators. This analysis has allowed to obtain significant differences between both processes; That is why a proposed model has been developed, which will be implemented using basic tools of process management to standardize the activities to be carried out and obtain better structured results that are aligned to increasing production levels and optimizing the use of means. The results obtained will be analyzed and used to generate indicators, which have been selected with the SMART technique, which allow us to compare the productivity obtained from the same piece of land before and after the improvement proposal. Finally, the proposed model will be consulted and validated using the expert judgment technique, for which we consult with users of SMEs in the sector and with experts in the management of process management tools. These results will be analyzed using the Pugh matrix as a tool to quantify the approval of each of the experts. / Tesis
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Garlic dry rot: a comprehensive study from field to fork on casual agents and disease management

MONDANI, LETIZIA 31 March 2021 (has links)
L’aglio è coltivato a livello mondiale nelle regioni temperate, secondo la FAO nel 2016 1.5 milioni di ettari sono stati destinati a questa coltura. A partire dal 2002 Fusarium proliferatum è stato segnalato come principale agente causale del marciume secco dell’aglio in post raccolta. I sintomi sono identificabili come macchie necrotiche sui bulbilli e in presenza di forti infezioni è possibile osservare la presenza di micelio bianco. F. proliferatum è un patogeno in grado di produrre Fumonisina B1 e B2, micotossine che potrebbero accumularsi all’interno dei bulbi ed essere tossiche per il consumatore. In Italia nel 2012 il 30% del raccolto è stato perso a causa di questo patogeno. Essendo la Fusariosi una malattia emergente a livello mondiale in letteratura si trovano ancora scarse informazioni sul suo sviluppo a livello di campo e sulle strategie di contenimento. 1. Allo scopo di verificare la quantità di inoculo fungino presente nell’ambiente si è proceduto all’analisi dei suoli in presemina con specifica attenzione alla quantificazione e all’identificazione delle specie fungine presenti. A tale scopo è stata eseguita: la conta delle Unità Formanti Colonia per grammo di terreno (UFC/g) su terreni specifici per l’isolamento del genere Fusarium spp. per grammo di terreno. Le identificazioni sono state eseguite al microscopio ottico e confermate successivamente con metodi molecolari. 2. Per seguire l’avanzamento della malattia durante la stagione colturale, invece, si è proceduto al campionamento in tre fasi fenologiche (inizio formazione dei bulbilli BBCH 15, ingrossamento dei bulbilli BBCH 45, maturazione di raccolta BBCH 49) con caratterizzazione dei sintomi, isolamento e riconoscimento dei funghi associati al marciume. 3. Per verificare la correlazione tra andamento meteo e incidenza delle specie fungine associate al marciume secco, sono stati raccolti i dati di meteorologici relativi al totale delle piogge, ai gradi giorno, all’umidità relativa media e alla temperatura media nei quadrati corrispondenti alle aziende agricole oggetto di studio. I dati sono stati correlati attraverso il coefficiente di correlazione di Pearson con i valori di gravità e incidenza della malattia stimati a fine stagione colturale. 4. Per verificare l’insorgenza dalla malattia nella fase di post raccolta si è proceduto con campionamenti di bulbi in conservazione, posa in piastra di bulbilli sintomatici e asintomatici e calcolo dell’incidenza delle specie fungine associate ai sintomi del marciume. 5. Al fine di verificare la possibile presenza di fumonisine nei campioni analizzati durante la stagione colturale e nel post raccolta, si è proceduto all’analisi attraverso HPLC di estratti di aglio. 6. Per individuare possibili strategie di controllo della malattia durante la stagione colturale sono stati eseguiti test di efficacia di prodotti chimici e biologici in vitro e in campo. I prodotti chimici sono stati provati su PDA modificato inoculato centralmente con F. proliferatum, mentre per gli agenti di biocontrollo sono state allestite prove di coltura duale. La prova in campo, invece, è stata eseguita all’interno di un campo sperimentale a strip plot. L’aglio delle diverse tesi è stato conservato in cella frigorifera per 9 mesi, per valutare la persistenza dei prodotti utilizzati alla concia. I risultati ottenuti hanno dimostrato che F. proliferatum e F. oxysporum sono le specie maggiormente associate al marciume dell’aglio durante la stagione colturale. L’andamento delle due specie è complementare e varia a seconda dell’andamento meteorologico della stagione colturale. F. proliferatum è correlato positivamente con l’aumento della temperatura e delle piogge, mentre F. oxysporum sembra prevalere nelle stagioni meno piovose ed ha mostrato correlazione positiva con la gravità dei sintomi rilevati in campo sulle corone. La carica micotica di Fusarium nel terreno rimane costante negli anni di analisi, facendo presupporre un maggiore ruolo del seme nella trasmissione della malattia. Per quanto riguarda il post raccolta, invece, F. proliferatum risulta la specie isolata con maggiore frequenza dai bulbilli e si correla positivamente ai sintomi rilevati sugli spicchi, confermando il suo ruolo come agente causale del marciume secco durante lo stoccaggio. F. oxysporum, invece, colonizza in prevalenza le radici e la parte basale della pianta dividendo il patosistema in due subsistemi: F. proliferatum-bulbi; F. oxysporum-radici. F. proliferatum è stato isolato anche dagli spicchi asintomatici con frequenza del 25%, ed è stato possibile rilevare la presenza di fumonisine con l’avanzare del tempo di stoccaggio in cella. Essendo il fungo presente anche sugli spicchi asintomatici maggiori studi saranno necessari per garantire la sicurezza dei consumatori. Infine, dalle prove di concia in campo è emerso che il principio attivo Tebuconazolo, riduce la comparsa dei sintomi da Fusarium, ma non in modo risolutivo. Ciononostante, una volta che il prodotto viene riportato a temperatura ambiente dopo lo stoccaggio in cella refrigerata, l’incidenza di F. proliferatum aumenta nuovamente con possibilità di sviluppo di danni al prodotto da commercializzare. / Since 2002, Fusarium proliferatum has been reported as the main causal agent of garlic dry rot during the postharvest stage, but information on the development of the disease throughout the production chain was nearly absent. Dry rot has caused huge economic losses in the past few years (up to 30 % of the yield), symptoms are visible on bulbs during storage as necrotic spots and in the most severe attacks, white mycelium may become visible on cloves. Few pest management strategies were tested in the recent past, but none were satisfactory. Due to the economic effect that this pathogen can have on local productions, the thesis aimed to deeply investigate the pathosystem with a field to fork approach and to test new strategies to control fungal infections. First of all, the work focused on garlic (Allium sativum L.) cropping season, intending to clarify the role of F. proliferatum in bulb infection as well as the impact of crop growing conditions on the development of the pathogen. A 3-year study was conducted in Piacenza (northern Italy) by sampling six garlic farms with different dry rot history (three highly contaminated and three low contaminated). Soil samples were recovered at sowing time for the counting of fungal colony-forming units (CFU). Plant samples were collected at three relevant growth stages, from April to July, for which disease severity assessment and fungi isolations were performed. Fusarium was the most frequently isolated genus, and F. proliferatum and F. oxysporum the dominant species during the garlic cropping season. F. oxysporum was dominant in the first year of the study, but F. proliferatum registered the highest incidence in all the farms tested. F. oxysporum incidence was correlated with dry weather, whereas F. proliferatum was enhanced in rainy years. To conclude, F. proliferatum is confirmed to be associated with garlic bulbs, even at crop’s early growth stages and symptoms are visible mainly on roots and basal plates at the field stage, related to F. oxysporum. Then, the focus was made in detecting the presence of F. proliferatum on garlic bulbs during prolonged storage, and to identify other fungal species associated with garlic dry rot. Moreover, fumonisin contamination in symptomatic and asymptomatic cloves were detected. Samples of 100 plants were collected over three production seasons in six farms located in Northern Italy at three-time points (at harvest, processing, and 6 months storage at –4° C). Results obtained lead to think that Fusarium–garlic pathosystem is split into two parts: basal plate/root and bulb. F. proliferatum had the highest incidence in infected bulbs and was confirmed as the causal agent of postharvest dry rot in garlic (mean incidence: 35.4%). F. oxysporum co-occurred with F. proliferatum but symptoms were visible only on basal plate/root. Dry rot incidence slightly increased during cold storage (from 14.6% at processing to 18.4% at 6-month storage); although, F. proliferatum incidence was stable during cold storage, fumonisin were produced from harvest through storage. Cloves showing symptoms were more contaminated compared to those asymptomatic, both by the fungus (mean incidence 39% vs 25.3%) and the toxin (287.0 vs 24.4 µg kg-1). Therefore, cold storage limits garlic dry rot, but health concerns related to fumonisin should be seriously considered. Regarding disease management, garlic crop is commonly propagated by plant parts (cloves). To protect garlic crop from early growth stages it is important to find commercial products able to control the pathogen growth on seedlings. The experiment aimed to test in vitro and in vivo the efficacy of triazoles and biocontrol agents (BCAs) against F. proliferatum and F. oxysporum. In in vitro trials, the best performance was achieved by propiconazole+prochloraz (100%), followed by tebuconazole (88.9%). BCAs were less effective but still showed great capacity to control the pathogen with maximum growth inhibition of 80% (Trichoderma harzianum +T. gamsii). In both cases, temperature influenced the capacity to control the pathogen with minimum effect at 25°C compared to lower temperatures. In vivo bacterial BCAs showed a similar capacity to control Fusaria compared to chemical products (mean of severity index 18.6% and 11.7%, respectively) and did not show side effects on root length. In vitro and in vivo results are comparable, except for Trichoderma, with the worst performances in terms of disease severity on plants. Finally, a field trial was designed to verify the efficacy of chemical and biological active ingredients as seed coating both at crop stage and postharvest, simulating the entire production chain, by taking into account visible symptoms and incidence of fungi. All products tested reduced the severity of symptoms on basal plates at the field stage, but none of them was able to reduce Fusarium incidence. A postharvest analysis conducted on bulbs demonstrated the efficacy of Tebuconazole, B. subtilis, and Trichoderma+B. subtilis in reducing the number of cloves showing symptoms per bulb (mean 34.3% vs control 45.8%). Moreover, Tebuconazole was able to reduce the incidence of F. proliferatum by 48% with respect to untreated control. The trial highlighted also that the incidence of F. proliferatum increased by 37% when garlic bulbs were kept for 15 days at room temperature simulating storage at consumers houses. Results obtained in the trial are promising and seed coating had a positive effect on garlic dry rot postharvest; although further studies are needed to test the persistence of seed coating treatments after prolonged storage period, especially when the product is kept outside cold chambers.
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Propuesta de proceso de distribución física mediante la cadena en frio para la conservación y la exportación de frambuesas orgánicas / Proposal for a physical distribution process through the cold chain for the conservation and export of organic raspberrie

Torres De La Cruz, Jorge Josué Manuel, Tardillo Mejía, Mijaíl Luis 11 November 2020 (has links)
La gestión de cadena de suministro, cada vez está tomando mayor importancia a nivel mundial, debido ya que es crítico para el logro de un buen producto final. Esta investigación describe la viabilidad de los procesos en la industria logística de la cadena de frío de la frambuesa en el Perú. El cultivo de frambuesas se encuentra en la etapa de oportunidades potenciales de crecimiento para la agroindustria. La logística de producción es una parte esencial de la gestión de la cadena de suministro de alimentos; esto mejora el rendimiento y la calidad del producto fresco. La cadena de frío y las buenas prácticas agrícolas preservan la calidad y reducen las pérdidas de producción de frambuesa en un 9%. Además, la implementación de una Gestión por procesos, en el tramo de pos cosecha hasta la llegada al aeropuerto, hicieron que este berrie, tenga la posibilidad de exportarse de tipo orgánica y estar al nivel de la competencia. Este modelo se basa en artículos científicos que son los pilares teóricos de la metodología de proceso que desarrolla la competitividad del producto. / Supply chain management is becoming increasingly important worldwide, as it is critical to achieving a good final product. This research describes the viability of the processes in the logistics industry of the raspberry cold chain in Peru. Raspberry cultivation is in the stage of potential growth opportunities for agribusiness. Production logistics is an essential part of managing the food supply chain; This improves the yield and quality of the fresh product. The cold chain and good agricultural practices preserve quality and reduce raspberry production losses by 9%. In addition, the implementation of a Management by processes, in the post-harvest section until arrival at the airport, made this berrie have the possibility of being exported organically and being at the level of the competition. This model is based on scientific articles that are the theoretical pillars of the process methodology that develops the competitiveness of the product. / Trabajo de suficiencia profesional
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La vie rurale en Syrie centrale à la période protobyzantine (IVe-VIIe siècle). / Rural life in Central Syria in the early Byzantine period (4th-7th century).

Rivoal, Marion 15 March 2011 (has links)
La Syrie centrale connaît au début de la période byzantine, et en particulier au Ve et au VIe siècle, un fort mouvement d’expansion des sédentaires vers l’est, qui coïncide avec une importante mise en valeur de ces nouveaux territoires. Comme pour d’autres régions de Syrie et du Proche-Orient à la même époque, un optimum climatique – pourtant déclinant – semble avoir permis la conquête et l’exploitation agricole de nouveaux terroirs dans une zone marginale qui n’avait jusqu’alors connu qu’une occupation sédentaire ponctuelle. La Syrie centrale est caractérisée par des milieux aux potentiels agronomiques très différents, souvent imbriqués. Le peuplement et la mise en valeur y sont soumis à la double contrainte de l’aridité climatique et édaphique, qui s’exerce avec une prégnance croissante vers le sud et l’est. Ces conditions, qui s’améliorent localement à la faveur de niches écologiques, ont permis à des politiques de mise en valeur et à des économies distinctes, souvent complémentaires, de voir le jour.Dans une région où les cités paraissent en grande partie absentes, l’économie repose d’abord sur les villages et sur quelques bourgs qui possédaient manifestement une orientation commerciale spécifique. Aux côtés des agglomérations, et souvent d’autant plus nombreux que les conditions d’implantation sont délicates, des fermes et des monastères s’affirment comme des acteurs économiques apparemment indépendants et souvent prospères. Des entités géographiques relativement homogènes ont donné lieu à une répartition des différentes formes de peuplement et à des économies microrégionales spécifiques. Si l’agriculture vivrière reste la règle, il semble bien cependant qu’on observe une spécialisation locale des productions : culture du blé et accessoirement plantations à l’ouest, oléiculture et peut-être viticulture dans les plateaux basaltiques du nord-ouest et vraisemblablement un élevage spéculatif, qu’on doit probablement attribuer à des populations sédentaires, dans les secteurs sud et est. / In Late Antiquity, especially between the 5th and 6th centuries, Central Syria witnessed a strong expansion of sedentary settlements eastward, which coincided with a significant agricultural development of these new territories. As for other areas in Syria and Near-East at the same period, a waning climatic optimum seems to have allowed byzantine population to settle down in marginal areas which barely experienced hitherto sedentary occupation and farm nearly unbroken lands.Central Syria is made up of various landscapes, sometimes deeply nested, with contrasted agricultural potential. Settlements and agricultural exploitation are affected by an increasingly significant climatic and edaphic aridity eastward and southward. These conditions, which may locally improve thanks to ecological niches, enabled specific and often complementary substance strategies to develop.In a country whence cities are virtually absent, villages and a few market towns seem to be at the very root of the regional economy. Along with agglomerations, scattered habitats – namely farmsteads and monasteries –, more numerous under heavy bioclimatic constraints, would appear as independent and apparently prosperous economic players.Homogeneous geographic areas led to specific settlement patterns and different economic orientations. Food-producing agriculture remains the rule, but a local productive specialization may be noticed: mainly wheat production and incidentally plantations westward, olive-growing and maybe wine-growing as well in the north-west basaltic plateaus and presumably speculative livestock exploitation eastward and southward, probably mostly due to sedentary populations.

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