No description available.

No description available.

Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and E. capsaeformis, and a common species Lampsilis fasciola, in the Clinch River, TN, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. These species use fish hosts with varying dispersal capabilities, ranging from low, moderate, and high, respectively. Patterns of mtDNA polymorphism exhibited different trends for long-term population sizes for each species during the Holocene (~10,000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained stable, and L. fasciola has expanded. Long-term effective population size (Ne) was smallest in E. brevidens, intermediate in E. capsaeformis, and highest in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. High levels of gene flow (Nm) were estimated among demes of L. fasciola using traditional F-statistics and likelihood estimates of Nm, whereas such metrics were lower in E. brevidens and E. capsaeformis. Data are consistent with population dynamics and life history traits of each species and their fish hosts. Age, shell growth, and population demography of Epioblasma brevidens, E. capsaeformis, and Lampsilis fasciola were studied from 2004-2007 in a 32-km reach of the Clinch River, TN. Observed maximum age and length of E. brevidens was 28 y and 71.5 mm for males and 11 y and 56.6 mm for females; of E. capsaeformis, 12 y and 54.6 mm for males and 9 y and 48.6 mm for females; and of L. fasciola, 45 y and 91.3 mm for males and 13 y and 62.6 mm for females. For all three species, observed maximum age and length was greater among males than females. Estimated population size in this river reach was approximately 43,000 individuals for E. brevidens, 579,000 individuals for E. capsaeformis, and 30,000 individuals for L. fasciola. Mean recruitment y-1 of 1 y-old E. brevidens ranged from 7.1% to 20%, of E. capsaeformis from 4.0% to 32.4%, and of L. fasciola from 5.8% to 25.6%. Population growth rate y-1 was 24.9% for E. brevidens, 34.6% for E. capsaeformis, and -22.4% for L. fasciola. Mortality rates of females were higher than for males of E. capsaeformis and L. fasciola, but not E. brevidens. Juvenile mussels were collected but temporally and spatially variable in occurrence, and a significant component of the age-class structure of all three species. Recruitment was very high during 2006-2007 for E. capsaeformis and other species, likely due to low river discharges in the spring-summer of 2005-2007. Surplus individuals of E. brevidens and E. capsaeformis are currently available to conduct translocations for restoration purposes. Population modeling of Epioblasma brevidens and E. capsaeformis in the Clinch River was conducted to determine suitable harvest levels for translocation of sub-adults and adults, and to determine quantitative criteria for evaluating performance and recovery of extant and reintroduced populations. For both species, the recommended annual harvest was <1% of local population size to minimize risk of decline. Reintroduction modeling indicated that size of the initial population created during a 5 y build-up phase greatly affected final population size at 25 y, being similar to size at the end of the build-up phase, especially when expected growth rate was low, (e.g., 1-2%). Excluding age-0 individuals, age-1 juveniles or recruits on average comprised approximately 11% and 15% of a stable population of each species, respectively. The age-class distribution of a stable or growing population was characterized by multiple cohorts, to include juvenile recruits, sub-adults, and adults. Molecular genetic and demographic data indicated that the ratio of Ne/Nc was ~5% for both species. Based on this ratio and predicted declines of genetic variation at different population sizes, target sizes for reintroduced or recovered populations of each species should be ≥5,000 individuals (Ne=250) and ≥10,000 individuals (Ne=500), respectively, and should be comprised of multiple smaller demes spread throughout a river. Populations of both species are currently large enough to sustain harvest for translocation and reintroduction purposes, offering an effective species recovery strategy. / Ph. D.

La transition nutritionnelle et l’insécurité alimentaire sont parmi les facteurs externes majeurs diminuant la qualité de l’alimentation. Les effets du déclin de celle-ci se résument par l’augmentation de la prévalence des maladies chroniques et des carences nutritionnelles. Afin de combattre ces problèmes, plusieurs études ont trouvé que la qualité de l’alimentation a été améliorée par l’autoproduction d’aliments (autorécolte*). Cette étude vise à identifier si un lien existe entre la qualité de l’alimentation et l’autorécolte d’aliments végétaux dans le contexte rural libanais, à partir de 748 748 répondants en provenance des régions du Chouf, Hermel et Aarsal. Afin de décrire l’alimentation selon le statut de récolte en ajustant pour différentes variables confondantes, des tests de χ2, d’ANOVA et des comparaisons multiples (Bonferroni) ont été effectués. Une interaction significative a été trouvée entre les deux types de récolte à tous les niveaux montrant que les collecteurs de plantes/fruits sauvages avaient tendance à produire domestiquement des fruits/légumes et vice versa. Le statut d’autorécolte d’aliments-sauvages avait une association positive et significative avec la variété et la fréquence de consommation à l’exception de celle des fruits et l’autorécolte domestique avait une association significativement positive avec la variété de consommation de légumes et la fréquence de consommation de fruits et légumes. Une forte association a été trouvée entre la région de résidence et les tendances de consommation de fruits/légumes. En outre, l’association entre l’autorécolte domestique et la fréquence de consommation des fruits et légumes s’est avérée positive dans la région où leur fréquence de consommation est la moins élevée (Hermel). Cette étude démontre que l'autorécolte des aliments végétaux, qu'ils soient produits dans un jardin-maison ou récoltés dans la nature, est significativement associée à une plus grande variété (diversité) et fréquence de leur consommation et que ces associations sont généralement liées à l'intensité de la récolte. Mots-clés: Transition nutritionnelle, insécurité alimentaire, autorécolte, autoproduction de fruits et légumes, collecte de plantes sauvages, variété, fréquence de la consommation alimentaire. *Dans ce document, le terme autorécolte d’aliments est utilisé pour inclure l’autoproduction et l’autocueillette d’aliments sauvages et le terme « aliments » reflète les groupes suivant : les fruits, légumes, plantes sauvages et fruits sauvages. / The nutrition transition and food insecurity are among the major external factors diminishing diet quality. The effects of diet quality decline can be summarized by the increase in the prevalence of chronic diseases and nutritional deficiencies. To combat these problems, several studies have found that diet quality has been improved by self-production of food (self-harvest*). This study aims to identify whether a link exists between diet quality and self-harvest of plant-food in the Lebanese rural context using data from 748 adult participants living in Chouf, Hermel and Aarsal. To describe dietary patterns of the study population according to the harveststatus, χ2, ANOVA and multiple comparisons (Bonferroni) were used while adjusting for various confounding variables. A significant interaction was found between the two types of harvest at all levels showing that collectors of wild plants/fruits tended to also have some domestic production of fruits and vegetables, and vice versa. While wild-food harvest had a significant positive association with the variety and frequency of consumption except for fruit consumption frequency, domestic harvest had a significantly positive association with vegetable consumption variety and fruit and vegetable consumption frequency. A strong association was found between the region of residence and fruit/vegetable consumption trends. Moreover, the association between domestic harvest and fruit/vegetable consumption frequency was only positive in the region where the consumption frequency was lowest (Hermel). This study demonstrates that self-harvesting of plant foods, whether produced in a home garden or collected from the wild, is significantly associated with greater consumption variety (diversity) and frequency of these foods and that these associations are generally related to the intensity of harvesting. Keywords: Nutrition transition, food insecurity, self-harvest of food, self-production of fruits and vegetables, wild plant harvest, food consumption variety, food consumption frequency. * In this document, the term self- harvest used to include the self-production of food and wild food collection. The term "food" reflects the following groups: fruits, vegetables, wild plants and wild fruits.

<p dir="ltr">Precision agriculture has been around for many, many years but as technology has rapidly grown with the population, farmers are looking for more ways to improve their operation with the help of these tools. These tools help farmers manage, understand, and decide when, how and what should be done regarding the tough decisions in the field based on their machinery statues. The tools that utilize GPS location and provide farm managers with useful information and feedback on large scales of value in the Harvesting and planting operation. With previous works done focusing on identify state machine activity utilizing GPS location data with the use of loggers and algorithms this study carries on from one field to the next identifying the truth data set for each and the accuracy of the algorithm. The goal is to add a more realistic view to the states identifying turning and transporting throughout the harvesting operation in truth data and from algorithm results. Also diving into truck activity with lower standard GPS tracking to see how accurately they can be predicted to complete the harvesting cycle from vehicle to vehicle. Overall, the combine and grain cart held at 88% accuracy for labeling all state activity during the harvesting operation for multiple fields, while for the model algorithm with the grain trucks having an overall accuracy of 94%.</p>

Tesis por compendio / [EN] Chitosan films and coatings have been obtained, by incorporating different essential oils (EO) and using different homogenization conditions of the film forming emulsions, in order to obtain antifungal materials for fruit preservation. The effect of oleic acid (OA) on the stability of the initial emulsions and on the film properties was analysed. Coatings were applied to control fungal decay in strawberries. The blending of chitosan with methylcellulose (MC) was also used in coating applications to tomato plants and fruits to prevent fungal infections. The films' functional properties as a function of their composition were analysed, as well as their antimicrobial activity through in vitro and in vivo tests. OA incorporation in the chitosan films (1:1 wt. ratio) reduced water vapour permeability (WVP) values to about 50 % of those of net chitosan films, with a small positive effect of the microfluidization process. EO (cinnamon, thyme and basil) did not notably reduced the WVP values of the chitosan films but a significant improvement in water barrier capacity was induced when OA was also added at 1:1 or 1:0.5 CH:OA ratios. In contrast, lipids slightly promoted oxygen permeability of the films. Lipid addition decreased the film stretchability and stiffness, with a lesser impact on the resistance to break, slightly depending on the droplet sizes. Essential oils also modulated the mechanical behaviour of the films, depending on their composition. Thyme and basil EO greatly promoted film stiffness and resistance to break, whereas cinnamon oil slightly reduced these mechanical attributes. Optical properties of the chitosan films were also affected by lipid incorporation. OA reduced the film transparency and gloss depending on the concentration, but provoked small changes in the colour parameters and whiteness index. EO affected transparency to a lesser extent, but had greater impact on the colour coordinates and whiteness index of the chitosan films due to the selective light absorption of their compounds. EO blend with oleic acid mitigated the colour changes in the films. Likewise, blending of OA with EO significantly reduced the losses of volatiles during the film formation due to the promotion of the stability of the film forming emulsions. Films containing cinnamon EO were effective in reducing the growth of Aspergillus niger, Botrytis cinerea and Rhizopus stolonifer, although thyme and basil EO encapsulated in the films did not exhibit antifungal action against these three fungi. When chitosan-cinnamon EO coatings were applied to strawberries inoculated with R. stolonifer, they reduced the fungal decay of the fruits during 14 days, at 10 °C, at the same time that total coliform counts were maintained at the initial levels. Chitosan coatings with lemon essential oil were also active at controlling fungal decay in strawberries. These did not significantly affect the physicochemical parameters of strawberries throughout cold storage, while they slowed down the respiration rate of the fruits and enhanced the chitosan antifungal activity against B. cinerea. The coatings, with and without lemon EO, affected the strawberry volatile profile, although it was only sensory appreciated for samples coated with chitosan-lemon oil. Blend films of CH and MC (1:1) containing oregano EO caused phytotoxic problems at "3 Leaves" stage of tomato plants, although the total biomass and crop yield was not affected. In the "Fruit" stage, the treatments had no negative effects. Coatings reduced the respiration rate of tomatoes, diminished weight loss during postharvest storage and were effective to decrease the fungal decay of tomatoes inoculated with R. stolonifer. Migration of thymol and carvacrol from CH-MC films in food simulants could overcome the stablished specific migration limit (60 mg/kg) for food contact packaging materials in aqueous and low pH systems if films contain a 1:1 polymer essential oil weight ratio. / [ES] En la presente tesis doctoral se han desarrollado diferentes materiales antifúngicos para su uso en conservación de frutas. Para ello, se han incorporado diferentes aceites esenciales (AE) en recubrimientos y películas de quitosano (Q). Se ha analizado el efecto de la adición de ácido oleico (AO) y las condiciones de homogeneización sobre la estabilidad de las emulsiones y sobre las propiedades de las películas. Se ha estudiado el efecto de los recubrimientos de Q sobre el deterioro fúngico en fresas y el efecto preventivo frente a infecciones fúngicas de las mezclas de metilcelulosa (MC) con Q en plantas de tomate. Se ha estudiado el efecto de la composición de las películas sobre las propiedades funcionales de las mismas, así como su actividad antimicrobiana in vitro e in vivo. La incorporación de AO en las películas de Q (proporción 1:1) redujo la permeabilidad al agua (PVA) en un 50% comparado con la de Q puro. La microfluidización indujo un efecto positivo sobre dicha reducción. La adición de AE (hoja de canela, tomillo o albahaca) no supuso una disminución notable de los valores de permeabilidad obtenidos para las películas de Q. Cuando se añadió AO a las formulaciones de Q y AE (proporciones 1:1 o 1:2), se promovió una mejora significativa en la PVA de las películas. En cambio, la adición de lípidos aumentó ligeramente la permeabilidad al oxígeno, disminuyó la elasticidad y la rigidez, y produjo un menor impacto sobre la resistencia a la rotura. A su vez, la adición de AE modificó el comportamiento mecánico de las películas. Los AE de tomillo y albahaca aumentaron considerablemente la rigidez y la resistencia a la rotura, mientras que el AE de hoja de canela redujo estos parámetros ligeramente. La adición de lípidos a las películas de Q afectó las propiedades ópticas de las mismas. El AO redujo la transparencia y el brillo, en función de la concentración añadida. La adición de AE tuvo un mayor impacto sobre los parámetros de color y el índice de blancura. Las mezclas de AE y AO mitigaron estos cambios de color. Además, la incorporación de las mezclas AE-OA redujo las pérdidas de volátiles del AE durante la formación de las películas. Las películas formuladas con el AE de hoja de canela fueron efectivas contra el crecimientos de A. niger, B. cinerea y R. stolonifer, aunque los AE de tomillo y albahaca encapsulados en las películas no mostraron ninguna actividad antifúngica. La aplicación de los diferentes recubrimientos de Q AE de C en fresas inoculadas con R. stolonifer dio lugar a una reducción en el deterioro fúngico de los frutos almacenados durante 14 días a 10°C. Los recubrimientos de Q-AE de limón también fueron efectivos en el control del deterioro fúngico en fresas. Estos recubrimientos no afectaron significativamente los parámetros físico-químicos de las fresas durante el almacenamiento en refrigeración, disminuyeron la tasa de respiración de los frutos y acentuaron la actividad antifúngica del Q frente a B. cinerea. Tanto los recubrimientos con AE como los de Q puro modificaron el perfil de volátiles de las fresas, aunque estos cambios solo fueron apreciados sensorialmente en el caso de los frutos recubiertos con AE. Las mezclas de Q y MC que contenían AE de orégano causaron efectos fitotóxicos en plantas de tomate en el estadio "3 hojas", aunque no afectaron a la biomasa total. En el estadio "frutos" los tratamientos no tuvieron ningún efecto negativo. Los recubrimientos redujeron la tasa de respiración de los tomates, disminuyeron la pérdida de peso durante el almacenamiento post-cosecha y fueron efectivos contra el deterioro fúngico de tomates inoculados con R. stolonifer. La migración de los compuestos fenólicos timol y carvacrol, contenidos en las películas de Q-MC, podría superar el límite de migración específica establecido (60 mg/Kg) para materiales de envase en contacto con alimentos en los casos de sistemas acuosos y d / [CA] En la present tesi doctoral s'han desenvolupat diferents materials antifúngics per al seu ús en conservació de fruites. Per a açò, s'han incorporat diferents olis essencials (OE) en recobriments i pel·lícules de quitosano (Q). S'ha analitzat l'efecte de l'addició d'àcid oleic (AO) i les condicions d'homogeneïtzació sobre l'estabilitat de les emulsions i sobre les propietats de les pel·lícules obtingudes. S'ha estudiat l'efecte dels recobriments de Q sobre la deterioració fúngica en maduixes i l'efecte preventiu enfront d'infeccions fúngiques de les mescles de metilcelulosa (MC) amb Q en plantes de tomaca. S'ha estudiat l'efecte de la composició de les pel·lícules sobre les propietats funcionals de les mateixes, així com la seua activitat antimicrobiana in vitro i in vivo. La incorporació de AO en les pel·lícules de Q (1:1) va reduir la permeabilitat al vapor d'aigua (PVA) en un 50% comparat amb la de Q pur. La microfluidització va induir un petit efecte positiu sobre aquesta reducció. L'addició de AE (fulla de canyella, C, timó, T, i alfàbrega, A) no va suposar una disminució notable dels valors de permeabilitat obtinguts per a les pel·lícules de Q. Quan es va afegir AO a les formulacions de Q i AE, es va promoure una millora significativa en la PVA de les pel·lícules. Per contra, l'addició de lípids va augmentar lleugerament la permeabilitat a l'oxigen, va disminuir l'elasticitat i la rigidesa, i va produir un menor impacte sobre la resistència al trencament. Al seu torn, l'addició de OE va modificar el comportament mecànic de les pel·lícules. Els OE de T i d'A van augmentar considerablement la rigidesa i la resistència al trencament, mentre que l'OE de C va reduir aquests paràmetres lleugerament. L'addició de lípids a les pel·lícules de Q també va afectar les propietats òptiques de les mateixes. L'AO va reduir la transparència i la lluentor, en funció de la concentració afegida. L'addició d'OE va tenir un major impacte sobre el paràmetres de color i l'índex de blancor. Les mescles d'OE i AO van mitigar aquests canvis de color. A més, la incorporació de les mescles OE-AO va reduir les pèrdues de volàtils de l'OE durant la formació de les pel·lícules. Les pel·lícules formulades amb l'OE de C van ser efectives contra el creixements d'A. niger, B. cinerea i R. stolonifer, encara que els OE de T i A encapsulats en les pel·lícules no van mostrar cap activitat antifúngica. L'aplicació dels diferents recobriments de Q OE de fulla de canyella en maduixes inoculades amb R. stolonifer va donar lloc a una reducció en la deterioració fúngica dels fruits emmagatzemats durant 14 dies a 10°C. Els recobriments de Q-OE de llimó també van ser efectius en el control de la deterioració fúngica en maduixes. Aquests recobriments no van afectar significativament els paràmetres fisicoquímics de les maduixes durant l'emmagatzematge en refrigeració, van disminuir la taxa de respiració dels fruits i van accentuar l'activitat antifúngica del Q enfront de B. cinerea. Tant els recobriments amb OE com els de Q pur van modificar el perfil de volàtils de les maduixes, encara que aquests canvis sol van ser apreciats sensorialment en el cas dels fruits recoberts amb OE. Les mescles de Q:MC que contenien OE d'orenga van causar efectes fitotòxics en plantes de tomaca en l'estadi "3 fulles", encara que no van afectar a la biomassa total. En l'estadi "fruits" els tractaments no van tenir cap efecte negatiu. Els recobriments van reduir la taxa de respiració de les tomaques, van disminuir la pèrdua de pes durant l'emmagatzematge post collita i van ser efectius contra la deterioració fúngica de tomaques inoculades amb R. stolonifer. La migració dels compostos fenòlics timol i carvacrol, continguts en les pel·lícules de Q-MC, podria superar el límit de migració específica establit (60 mg/Kg) per a materials d'envàs en contacte amb aliments en els casos de sistemes aquosos i d / Perdones Montero, Á. (2015). ANTIFUNGAL CHITOSAN-BASED FILMS AND COATINGS CONTAINING ESSENTIAL OILS FOR FRUIT APPLICATIONS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59413 / Compendio

Ce travail de thèse a permis de décrire la contamination importante des grains du café de (Coffea canephora variété robusta) par des moisissures au cours des traitements post récolte des cerises de café par la voie sèche, dans une zone tropicale humide. La stratégie d’échantillonnage mise en place à consister à faire des prélèvements durant deux années successives (2008 et 2009) sur des sites localisés dans les principales zones de production du café en Côte d’Ivoire. A partir de 31 échantillons de cerises, grains et coques de café, 218 souches sauvages de moisissures ont été isolées sur milieu Potato Dextrose Agar (PDA) et identifiées. Ces champignons filamenteux sont répartis comme suit : Aspergillus section Nigri (52%) ; Aspergillus verts (13%), Penicillium (10%), Mucor (16%), Fusarium (4%), autre (5%). Les Aspergillus section Nigri qui comptent le complexe Aspergillus niger agreggate et Aspergillus carbonarius représentent un peu plus de la moitié de la population fongique soit 52%, soit 30% en 2008 et 70% en 2009, de la flore fongique totale. Ce groupe a fait l’objet d’une caractérisation morphologique. L’étude du potentiel mycotoxinogène des Aspergillus section Nigri isolées du café robusta a démontré qu’en plus de l’OTA, certaines souches d’Aspergillus Nigri produiraient de l’aflatoxine. Cependant l’espèce Aspergillus carbonarius reste la plus ochratoxinogène (0,6 µg et 15µg d’OTA/g de milieu gélosé). En plus des moisissures 44 souches de bactéries lactiques (LAB) ont été isolées à partir de la pulpe fraîche de café. Les caractères morphologiques, biochimiques et culturaux ont été étudiés. L’identification moléculaire des bactéries a permis de les classer dans le groupe de Lactobacillus plantarum sp. Après un criblage orienté, deux souches de LAB avec un effet important d’inhibition de croissance des moisissures mycotoxinogènes ont été sélectionnées. Les deux souches de Lactobacillus plantarum ont démontré une activité antifongique contre les souches d’Aspergillus carbonarius hautement ochratoxinogènes. Par conséquent la prévention de la mycotoxinogenèse sur café robusta, pourrait passer par l’inhibition de la croissance de certaines moisissures ochratoxinogènes. Les résultats acquis au cours de ce travail de thèse serviront de base afin de poursuivre cette étude d’une part avec des essais in situ pour tester l’efficacité des LAB sélectionnées et d’autre part, rechercher les biomolécules actives contre la germination des spores contaminants naturels post récolte en particulier des cerises de café en Côte d’Ivoire et des fruits et légumes en général. / One of the objectives of this thesis was to describe the significant contamination of robusta coffee beans (Coffea canephora) by moulds during the post-harvest processing of coffee cherries in the dry process. The sampling strategy was to take samples for two consecutive years (2008 and 2009) from different areas of coffee production in Ivory Coast and on the other hand, from the same area but from coffee producers using different methods of drying of coffee beans. From 31 samples, 218 wild strains of fungi were isolated on Potato Dextrose Agar (PDA) media and identified. These filamentous fungi were as follows: black Aspergilli (52%); green Aspergilli (13%), Penicillium (10%), Mucor (16%), Fusarium (4%) and others (5%). The black Aspergilli were found to include Aspergillus niger and Aspergillus carbonarius representing 52% of the fungal population, with a proportion of 30% in 2008 and 70% in 2009 of the total fungal flora. This group was selected to study more about their mycotoxin production. Most strains grown on media and at specific incubation conditions, were capable of producing one or more kinds of mycotoxins. Analysis of mycotoxins from fungi isolated from less than a hundred robusta coffee showed that ochratoxin A (OTA) was not the only mycotoxin that may contaminate the robusta coffee in Ivory Coast. Indeed, several strains belonging to the species Aspergillus Nigri group had shown their ability to produce not only ochratoxin A but also aflatoxin. However, the species A. carbonarius remains as the most ochratoxigenic strain but it does not produce aflatoxin.In parallel to the isolation of fungi, 44 strains of lactic acid bacteria (LAB) were also isolated from fresh coffee cherries, harvested in Ivory Coast in 2009. The morphological, biochemical and growth characteristics were studied. Molecular identification of strains ranked them to be in the group of Lactobacillus plantarum sp. After a screening experiment, it was possible to select two strains of LAB with a significant effect of inhibiting fungal growth by producing mycotoxins. The two strains of Lactobacillus plantarum showed antifungal activity against strains of Aspergillus carbonarius which is highly ochratoxigenic. Therefore the prevention of mycotoxigenicity of robusta coffee, could be rised by inhibiting the growth of certain ochratoxigenic fungi. The results achieved in this thesis serve as a basis to continue the study on one hand with field trials to test the effectiveness of selected LAB on the other hand, look for active biomolecules against spore germination of contaminants especially the natural post-harvest coffee beans in Ivory Coast and fruits and vegetables in general.

O Brasil é o segundo maior produtor e exportador de soja (Glycine max L. Merrill) no mundo. A produção é altamente dependente de fatores climáticos, incluindo a temperatura e quantidade de chuva. A soja cultivada no sul do país em 2005 sofreu déficit hídrico causado por temperaturas altas acompanhado por umidade baixa durante o estádio reprodutivo. Pouco se sabe sobre a influência do déficit hídrico na degradação da clorofila e na qualidade dos grãos em geral. Nesse trabalho foram analisadas, numa primeira etapa, as características químicas e bioquímicas de cinco amostras de soja, provenientes de três cultivares que cresceram sob déficit hídrico e que não atendiam aos padrões para comercialização por conter altas quantidades de sementes verdes. Os grãos foram analisados quanto a diversos parâmetros físico-químicos e bioquímicos incluindo a análise dos pigmentos verdes imediatamente após a colheita e após 20 meses de armazenamento. A acidez foi medida adicionalmente após 30 meses de armazenamento. A atividade de água e umidade foram 0,6-0,7 e 8,7 %-11,9 %, respectivamente, e não mudaram durante a estocagem, mas houve um aumento em acidez o que indica atividade de lipases. A atividade da lipoxigenase 1 foi significativamente prejudicada. Imediatamente após a colheita os pigmentos verdes correspondiam a feofitina a, feofitina b e pequenas quantidades de clorofila a e b, e traços de outros derivados da clorofila, em ordem decrescente. Após 20 meses de estocagem quase todos os pigmentos haviam desaparecido. O déficit hídrico provavelmente aumentou a permeabilidade das membranas, o que levou a um aumento do pH e promoveu a transformação das clorofilas para feofitinas. Na segunda etapa do trabalho foi estudado o estágio avançado da degradação natural da clorofila na qual desaparece a coloração esverdeada dos grãos. Esta etapa corresponde à formação de catabólitos incolores (NCC), mas existem controvérsias se essas substâncias são os produtos finais da degradação. Assim, foram investigadas a formação e degradação dos NCC durante a maturação da soja e o efeito do tratamento térmico pós-colheita. A soja foi colhida em seis estádios de maturação e a formação dos NCC foi analisada por HPLC após secagem dos grãos a 40 e 60°C. Todas as amostras contiveram frações com um máximo de absorbância a 320 nm, considerado típico para os NCC. Os teores aumentaram até o 114o dia após a semeadura e decresceram significativamente em estádios mais avançados de maturação. Nas amostras secas a 40 e 60°C os teores de NCC foram menores, devido a níveis iniciais de clorofila inferiores. Esses resultados indicam que os NCC em soja provavelmente não sejam os produtos finais da degradação da clorofila. A sua redução em estádios mais avançados de maturação indica a sua metabolização para outras substâncias. / Brazil is the second largest soybean (Glycine max L. Merrill) producer and exporter in the world. The production depends on climatic factors, like temperature and rain volume. Soybeans cultivated in the south of the country in 2005 suffered drought stress imposed by adverse high ambient temperature, accompanied by low humidity during the reproductive stage. Little information is available regarding drought stress on quality of grains. In this study, firstly, chemical and biochemical characteristics of five soybean samples belonging to three cultivars grown under drought stress and did not meet standards for marketing due to high amounts of green seeds, were evaluated. Grains were analyzed for several physicochemical ad biochemical parameters, including analysis of pigment contents, immediately after harvest and after 20 months of storage at room temperature. Acidity was measured additionally after 30 month of storage. Water activity and humidity were 0.6 - 0.7 and 8.7 % - 11.9 %, respectively, and did not change during storage time, but there was an increase in acidity, which alludes to lipase activity. The activity of lipoxygenase 1 was significantly prejudiced. Immediately after harvest, green pigments corresponded mainly to pheophytin a, followed by pheophytin b, small quantities of chlorophyll b and chlorophyll a and traces of other chlorophyll derivatives. After 20 months of storage almost all green pigments had disappeared. Drought stress probably enhanced membrane permeability, which led to a lower pH and promoted transformation of chlorophylls to pheophytins. In the second part of the study, the advanced stage of natural chlorophyll degradation was investigated, in which the green colour of the seeds disappears. This stage corresponds to the formation of non-coloured chlorophyll catabolites (NCC), but there are controversies if those are the final products. Thus, the formation and degradation of NCC during soybean (Glycine max L. Merrill) maturation and two post-harvest drying temperatures was investigated. Soybean was harvested at six maturation stages and the formation of NCC was analyzed by HPLC after drying at 40°C and 60°C. All samples contained fractions with an absorption maximum at 320 nm, which are considered typical for NCC. The amounts of NCC increased until 114 days after plantation, and were significantly lower in advanced maturation stages. In samples dried at 40°C and 60°C, NCC amounts were lower, due to inferior initial chlorophyll levels. These results indicate that the NCC in soybeans might not be the final products of chlorophyll degradation. Their reduction in advanced maturation stages may be due to further metabolization.

O Brasil é considerado o maior produtor de citros e o maior exportador de suco de laranja. Doenças de pós-colheita representam uma grande perda na citricultura, sendo que para muitos frutos a serem exportados, existe uma exigência para que os mesmos estejam isentos de resíduos químicos. Em relação a alguns patógenos de importância em pós-colheita podemos destacar, Guignardia citricarpa (Mancha-pretados- citros), Penicillium digitatum (Bolor-verde) e Colletotrichum gloeosporioides (Antracnose). Dada a importância econômica que representa esse complexo de doenças dos frutos cítricos, tanto em termos de comprometimento da qualidade dos frutos, limitações às exportações e dificuldade de controle, a busca de alternativas adicionais que possam viabilizar a capacidade produtiva dos produtores e garantir a obtenção de frutos com excelentes padrões de qualidade torna-se imprescindível. Nesse contexto, pode-se inserir o emprego de medidas de controle alternativas que não englobam o controle químico clássico. Sob esse ponto de vista inclui-se o controle através do uso de agentes bióticos e abióticos e a indução de resistência em plantas. Portanto neste trabalho, foi estudada a viabilidade do controle de doenças pós-colheita em citros, envolvendo a ação direta sobre os patógenos através do uso dos extratos etanólicos de albedo (mesocarpo) de laranja doce (Citrus sinensis var. Valência) e flavedo (exocarpo ou epicarpo) de limão-Tahiti (Citrus aurantifolia Swing var. Tahiti). O extrato do albedo apresentou efeito antifúngico sobre G. citricarpa e o flavedo do limão "Tahiti" sobre C. gloeosporioides, além de se demonstrar a existência de compostos voláteis com efeito tóxico. A segunda parte envolveu o controle e a indução de resistência em frutos, através do uso dos agentes bióticos Lentinula edodes e Agaricus blazei e do agente abiótico ácido jasmônico. Foi possível observar que o extrato aquoso do albedo (C. sinensis), flavedo (C. aurantifolia), L. edodes e A. blazei diminuíram o aparecimento de novas lesões causadas por G. citricarpa, porém não apresentaram efeitos sobre P. digitatum e C. gloeosporioides em frutos de C. sinensis var. Valência quando tratados em pós-colheita. Dessa maneira, no presente trabalho demonstrou-se a viabilidade de um possível controle alternativo de doenças pós-colheita em citros, buscando-se novos agentes que atuem como indutores de resistência ou de controle direto sobre os fitopatógenos. / Brazil is considered the biggest citrus producer and the biggest orange juice exporter. Post-harvest diseases represent a great loss in the citriculture, and for many fruits to be exported they should be free of chemical residues. In relation to some pathogens of importance in post-harvest it can be mentioned Guignardia citricarpa (black-spot-ofcitrus), Penicillium digitatum (green-mold) and Colletotrichum gloeosporioides (anthracnose). Because of the economical importance that represents this disease complex in citric fruits, in terms of compromising fruit quality, limitations to the exports and control difficulties, the search for alternative control measures that can make possible improve the producing capacity of the producers and the obtaining of fruits with excellent quality are indispensable. Thus, in this context it can be included measures of alternative control that do not include the chemical control. Under this point of view, control include the use of biotic and abiotic agents and the resistance induction in plants. Therefore, it was studied the viability of the control of post-harvest diseases in citrus, involving the direct action on the patogens by using ethanolic extracts of albedo (mesocarp) of sweet orange (Citrus sinensis var. Valência) and flavedo (exocarp or epicarp) of lemon-Tahiti (Citrus aurantifolia Swing var. Tahiti). The results showed that the extract of the albedo exhibited antifungal activity on G. citricarpa and the flavedo of the "Tahiti" lemon on C. gloeosporioides, and it was also demonstrated the existence of volatile compounds toxic to the fungus. The second part involved the control and resistance induction in the fruits, by using the biotic agents Lentinula edodes and Agaricus blazei and the abiotic agent jasmonic acid. It was possible to observe that the aqueous extracts from the albedo (C. sinensis), flavedo (C. aurantifolia), L. edodes and A. blazei reduced the formation of new lesions caused by G. citricarpa, however they did not exhibit effects on P. digitatum and C. gloeosporioides in fruits of C. sinensis var. Valência when treated in post-harvest. Thus, in the present work it was demonstrated the viability of possible alternative control measures of diseases in post-harvest of citrus, indicating the need of looking for new agents to act as resistance inducers or agents to directly control on the phytopathogens.

O palmiteiro (Euterpe edulis Mart.) é uma espécie nativa da Mata Atlântica cujas populações naturais encontram-se degradadas pelo extrativismo. Considerando a escassez de informações relativas às conseqüências genéticas da exploração de palmito, o objetivo deste estudo foi avaliar o impacto do processo de exploração sobre os níveis de diversidade, estrutura genética e tamanho efetivo de populações da espécie. Também foram estudados aspectos genéticos do recrutamento de plantas e o sistema reprodutivo da espécie. O estudo foi realizado em duas localidades do Estado de Santa Catarina, nos municípios de São Pedro de Alcântara e Ibirama. Em cada localidade foram escolhidas duas áreas de ocorrência natural de E. edulis, uma sem influência antrópica e outra que sofreu exploração de palmito, totalizando quatro populações. Os sistemas de exploração foram: (i) extrativismo - onde todos os indivíduos acima de 2 m de altura são cortados, incluindo plantas reprodutivas; and (ii) manejo - onde somente indivíduos acima de 9 cm de DAP são cortados, com a manutenção de 50 plantas reprodutivas por hectare. Em cada população foram examinadas plântulas, jovens e adultos, usando oito locos microssatélites e dez locos alozímicos. Os resultados revelaram que a espécie se reproduz por alogamia ( m tˆ = 0,996 para microssatélites e m tˆ = 1,000 para isoenzimas), porém a ocorrência de cruzamentos entre indivíduos aparentados (até 5%) e cruzamentos biparentais (10%) indica a ocorrência de cruzamentos não aleatórios. Em locos alozímicos, observaram-se as seguintes amplitudes de variação das estimativas de diversidade entre as categorias: Aˆ : 3,05 a 3,15; e Hˆ : 0,416 a 0,431; o Hˆ : 0,378 a 0,403. Em locos microssatélites, a variação observada foi a seguinte: Aˆ : 14,12 a 14,72; e Hˆ : 0,781 a 0,785; o Hˆ : 0,678 a 0,709. Nas populações não exploradas, houve um aumento na freqüência de heterozigotos na direção do estádio adulto, o que sugere a ação da seleção favorecendo o aumento de heterozigotos. Valores altos e significativos do índice de fixação ( fˆ ) foram observados, especialmente nos marcadores microssatélites, indicando desvios do equilíbrio de Hardy-Weinberg. De modo geral, ambos os marcadores revelaram um aumento dos valores de fˆ nas populações exploradas, especialmente entre as plântulas. As estimativas ST Gˆ e ST Rˆ não revelaram alterações na estrutura genética das populações exploradas e demostraram uma divergência genética inferior a 5% na maioria das comparações aos pares, em ambos os marcadores. O tamanho efetivo ( e Nˆ ) dos indivíduos adultos por hectare foi superior a 110 nas populações não pertubadas, enquanto nas populações exploradas, o tamanho efetivo por hectare foi reduzido para 45, sob manejo, e 14, sob extrativismo. Porém, o tamanho efetivo total das populações exploradas ainda é elevado, o que explica a manutenção dos altos níveis de diversidade nessas populações. Finalmente, a informação genética conjunta desses marcadores demonstrou que os efeitos da exploração foram pouco pronunciados até o momento em relação aos níveis de diversidade e estrutura genética das populações de E. edulis. Entretanto, a redução da população de cruzamentos resultou em alterações no comportamento reprodutivo dos indivíduos, promovendo um aumento nos níveis de endogamia nas coortes mais jovens das populações exploradas. Contudo, os resultados obtidos neste estudo indicaram questões adicionais a serem estudadas. Em função do elevado nível de variabilidade dos locos microssatélites observado em E. edulis, recomenda-se aumentar o tamanho das amostras visando otimizar a informação genética proporcionada por esses marcadores. Além disso, novos estudos são necessários sobre os efeitos do manejo tecnificado, uma vez que os resultados obtidos podem ter sido influenciados por outros eventos de exploração ocorridos no passado e pelas populações existentes nas proximidades devido ao elevado fluxo gênico da espécie. / Heart-of-palm tree (Euterpe edulis Mart.; Arecaceae) is a native species of the Atlantic forest whose natural populations are degraded by extractivism. Regarding the relative scarcity of information on the genetic consequences of palm heart exploitation, the aim of this study was to investigate the effects of two exploitation systems - extractivism and management - on the levels of variability, genetic structure and effective size of Euterpe edulis Mart. populations. We also investigated genetic aspects of the plant recruitment and the reproductive system of the species. Four natural populations of E. edulis with different histories of disturbance were surveyed in the districts of São Pedro de Alcântara and Ibirama, Santa Catarina, Brazil. At both sites, we sampled an undisturbed and an exploited population. The exploitation systems were: (i) extractivism - where most individuals higher than 2 m are harvested, including reproductive plants; and (ii) management - where only individuals with more than 9 cm of DBH are harvested, with the maintainance of 50 reproductive plants per ha. Three categories of plants, from seedlings to adults, were examined using eight microsatellite loci and ten allozyme loci. Results demonstrated the preferentially allogamic behaviour of the species ( m tˆ = 0.996 for microsatellites and m tˆ = 1.000 for allozymes), but the occurrence of matings among related individuals (5%) and biparental matings (10%) indicated the existence of non-random matings in this species. For allozymic loci, the following diversity estimates were obtained among the categories: Aˆ : 3.05 to 3.15; e Hˆ : 0.416 to 0.431; o Hˆ : 0.378 to 0.403. For microsatellites, the estimates were as follows: Aˆ : 14.12 to 14.72; e Hˆ : 0.781 to 0.785; o Hˆ : 0.678 to 0.709. In undisturbed populations, there was an increase in heterozygote frequency towards the adult stages, suggesting the action of natural selection favouring such heterozygote increase. Highly significant values of fixation index ( fˆ ) were observed, mainly at microsatellite loci, indicating departures from Hardy-Weinberg expectation. Both markers displayed an increase of fˆ values in the exploited populations, especially for seedlings. The estimates of interpopulation genetic variation ( ST Gˆ ; ST Rˆ ) revealed that more than 95% of the molecular genetic variability of the species is distributed within populations, and there was no evidence of changes in genetic structure of the exploited populations. Effective size ( e Nˆ ) per hectare of the adult individuals was higher than 110 in the two undisturbed populations, while in the exploited populations the effective size per hectare was reduced to 45 under management, and 14 under extractivism. However, the total effective size of the exploited populations was still high, which explains the maintenance of high diversity levels in these populations. Finally, the genetic information from both markers displayed small pronounced effects of the exploitation process on variability and population genetic structure of E. edulis, with the exception of an increase in the inbreeding levels among seedlings and juveniles of the exploited populations. However, our results raised further questions for study. Because of the hypervariability of microssatellite loci used in this work, we would recommend an increase in the sample size (>100) in order to optimize the genetic information provided by these markers. Moreover, new investigations are necessary on the effects of management, since the results from this study could have been influenced by other exploitation events that have occurred in the past and by the existence, due to the high gene flow of the species, of surrounding undisturbed populations.