Made available in DSpace on 2014-08-20T14:22:07Z (GMT). No. of bitstreams: 1 Dissertacao_ Zeni_Fonseca_Pinto_Tomaz.pdf: 537146 bytes, checksum: 4410efffebf745b503737ec2db7a1acb (MD5) Previous issue date: 2009-03-31 / In Brazil, most peach production is concentrated in the state of Rio Grande do Sul. This sector involves working on small families farms. The increase in the product demand brings out the critical level of the consumers regarding to product quality. Therefore, the market requires new attributes accomplished to the product; considering aspects such as organoleptic characteristics, food security and environmental protection. This work aimed to reduce peach tree vigor of the cultivar Jubileu by using different interstocks length of Granada . It was carried evaluations to indicate the better length of interstock to promote tree vigor reduction without significatively altering phenological and productivity characteristics, and fruit quality. And also, it was measured the effect of different interstock lengths on flowering and harvesting time, yield and qualitative characteristics of the fruits. The experiment was carried out at the Centro Agropecuário da Palma belonging to the Faculdade de Agronomia Eliseu Maciel of the Universidade Federal de Pelotas. Important part of the vegetative growth and production of peach cv. Jubileu is directly related to interstock length. The increase in interstock length anticipates the beginning of flowering and full bloom. The vigor reduction induced by the longer interstocks promotes an increase in floral differentiation. The twenty cm length interstock promotes an increase in plant mortality; therefore, it is indicated Granada interstocks with 10 and 15cm length. The use of intergrafting, independently interstock length, has little effect on physic-chemical characteristics of the fruits. Ten and fifteen cm length interstock were most efficient for yield without altering peach quality of Jubileu . / No Brasil, a maior produção persícola concentra-se no Rio Grande do Sul. Esse pólo envolve famílias que exploram a atividade em pequenas áreas. Aliado ao aumento da demanda, cresce também o grau de exigência dos consumidores quanto à qualidade do produto, ou seja, o mercado passou a exigir novos atributos, contemplando aspectos ligados às características organolépticas, à segurança alimentar e a proteção do ambiente. Com o presente trabalho objetivou-se avaliar a interenxertia para reduzir o vigor das plantas de pessegueiro da cultivar Jubileu através do emprego de diferentes comprimentos de interenxertos da cv. Granada. O trabalho constou de um experimento, no qual foram realizadas avaliações para indicar o comprimento de interenxerto que promova a redução do vigor das plantas e avaliar o efeito dos diferentes comprimentos de interenxerto na floração, colheita, na produção e nas características qualitativas das frutas. O experimento foi desenvolvido no Centro Agropecuário da Palma da Faculdade de Agronomia Eliseu Maciel da Universidade Federal de Pelotas. Os principais resultados obtidos permitem concluir que o crescimento vegetativo e a produção do pessegueiro Jubileu está diretamente relacionada com o comprimento do interenxerto. O aumento do comprimento do filtro antecipa o início da floração e a plena floração. A redução do vigor induzida pelos interenxertos de maior comprimento promove aumento na diferenciação floral. O interenxerto de 20cm promove aumento da mortalidade das plantas e, portanto, para o adensamento de pomares, indica-se o emprego de filtros da cv. Granada com comprimento entre 10 e 15cm. O emprego da interenxertia, independentemente do comprimento do interenxerto, afeta as características físico-químicas dos pêssegos Jubileu . Os interenxertos de 10 e 15cm de comprimento foram mais eficientes na produção, sem alterar a qualidade dos pêssegos Jubileu .

Le manguier (Mangifera indica L.), cinquième production fruitière mondiale, est une espèce à production irrégulière. L’irrégularité de production a des retombées économiques marquées pour tous les acteurs de la filière fruitière. Il apparait donc important de mieux comprendre les mécanismes qui déclenchent et entretiennent ce phénomène d’irrégularité de production. Le premier objectif de cette thèse est d’apporter un regard nouveau sur l’irrégularité de production du manguier en mobilisant le concept des coûts de la reproduction. Cette étude est effectuée à plusieurs échelles spatiales, unité de croissance (UC), branche charpentière, arbre, et de manière dynamique sur quatre cultivars. Les résultats montrent un effet négatif, ou coût, de la reproduction sur la croissance végétative au cycle suivant, avec des comportements contrastés des cultivars en lien avec leur irrégularité de production. En particulier, un effort reproducteur important diminue la probabilité de débourrement végétatif des UCs porteuses. Le second objectif est d’étudier, chez deux cultivars et à l’échelle de l’UC, les modifications anatomiques et hydrauliques liées à la croissance du fruit, et des mécanismes trophiques et hormonaux contribuant à cet effet négatif de la reproduction sur le débourrement végétatif. Les résultats montrent que la reproduction entraîne une différenciation du cambium de l’UC porteuse principalement en phloème. Les inflorescences et les fruits diffusent de l’auxine qui inhibe le démarrage végétatif des UCs reproductrices. Les fruits en croissance mobilisent les réserves en amidon de l’UC porteuse. Les faibles teneurs en amidon de ces UCs pendant et après la récolte contribuent à réduire leur probabilité de débourrement végétatif, et/ou à le retarder lorsqu’il a lieu. Les résultats diffèrent entre les deux cultivars, et l’implication de ces mécanismes dans l’irrégularité de production est discutée. Nos résultats permettent de mieux comprendre les facteurs qui entretiennent l’irrégularité ou l’alternance de production de différents cultivars de manguiers. De façon appliquée, ils suggèrent que des techniques de taille adaptées à chaque cultivar et nature d’UC pourraient permettre d’obtenir une production plus régulière chaque année. / The mango tree (Mangifera indica), the fifth fruit crop production in the world, is characterized by an irregular bearing pattern. Irregular bearing is responsible for economic difficulties for producers and for all actors along the fruit industry chain. A better understanding of mechanisms which trigger and maintain irregular bearing is therefore necessary. The first objective of this study is to provide a new perspective on irregular bearing of the mango tree using a concept developed in ecology and evolutionary biology, the costs of reproduction. The experiment was carried out dynamically at several spatial scales, growth unit (GU), scaffold branch, tree, and on four cultivars. Results show a negative effect, or cost, of reproduction on vegetative growth during the following cycle, with cultivar-specific behaviors related to their bearing pattern. In particular, an important reproductive effort reduces the probability of vegetative burst of the bearing GUs. The second objective is to study, for two cultivars and at the GU scale, the anatomical changes of the bearing axis during fruit growth, and hormonal and trophic mechanisms involved in the negative effects of reproduction on vegetative bud outgrowth. Results show that reproduction leads to cambium differentiation mainly in phloem, favoring nutrients and water supply to the fruit. Inflorescences and growing fruits release auxin, contributing to vegetative bud burst inhibition on fruiting GUs. Growing fruits mobilize starch reserves of bearing GUs. Their low starch content at and after harvest contributes to decrease their probability of vegetative burst, and/or delay it when it occurs. The results reveal a strong cultivar effect, and the involvement of these mechanisms in irregular bearing is discussed. Our results allow to better understand the factors maintaining irregular or alternate bearing of different mango cultivars. From a practical perspective, they suggest that pruning techniques adapted to each cultivar and GU fate may contribute to more regular production each year.

The production of grapes depends on the soil where the grape grown where it absorbs water and nutrients necessary for their development. High levels lead to a sharp growth, while in poor soils with low fertility and there is development of short internodes and leaves small. Searching a solution to this problem is proposed this work, with the aim of suggesting standards of nitrogen for different conditions of cultivation of the garden, through the determination of different fractions of nitrogen during growth: flowering, 30 days after flowering, "vèraison ", harvest and fermentation, in three varieties viníferas: Cabernet Sauvignon, Merlot and Pinot noir. Total Nitrogen was analyzed through micro-Kjedahl method. Ammonia and assimilable nitrogen were determined distillation and titration with formaldehyde, respectively. For a variety Cabernet Sauvignon, the values of total nitrogen were: in flowering 1,3 g %, 30 days after the flowering 0,58 %; in "vèraison" 264,2 mg/L and harvest 303,7 mg/L. The values of ammoniacal nitrogen were 126,3 mg/L in "vèraison" and 46,6 mg/L in harvest, while assimilable nitrogen was of 101,0 mg/L and 131,0 mg/L, for the same period. For Merlot variety, total nitrogen was 1,24 g % in flowering; 0,64 g % 30 DAF; 209,4 mg/L in "vèraison" and 327,8 mg/L in harvest. Ammoniacal nitrogen was 86,3 and 25,5 mg/L for "vèraison" and harvest, respectively, while assimilable nitrogen was of 67,0 and 86,0 mg/L, for the same period. For Pinot noir, total nitrogen was 1,65 and 0,57 g % in flowering and 30 DAF, respectively; 95,3 mg/L in "vèraison" and 140,9 mg/L in the harvest. For the ammoniacal nitrogen, the figures were 36,0 and 18,1 mg/L in the "vèraison" and the harvest, in that order, whereas, for the amount assimilable nitrogen was of 56,0 and 63,3 mg/L for the same period. Three varieties were similar during vegetative cycle and fermentation, however, the smaller quantities of total nitrogen at harvest, for Pinot noir lead us to suggest a nitrogen fertilization in the period between 30 and DAF "vèraison". / A produção de uvas de qualidade para fabricação de vinhos depende diretamente do solo onde a videira é cultivada e de onde esta absorve água e nutrientes necessários ao seu desenvolvimento. Teores muito elevados levam a um crescimento vegetativo acentuado, enquanto que em solos pobres e com baixa fertilidade há desenvolvimento de entrenós curtos e folhas pequenas. A fim de solucionar este problema foi proposto o presente trabalho, com a finalidade de sugerir padrões de nitrogênio para diferentes condições de cultivo do parreiral, através da determinação de diferentes frações de nitrogênio durante o ciclo vegetativo: floração, 30 dias após a floração, vèraison , colheita e fermentação, em três variedades viníferas: Cabernet Sauvignon, Merlot e Pinot noir. Nitrogênio total foi analisado através do método micro-Kjedahl. Amônia e nitrogênio assimilável foram determinados através de destilação por arraste de vapor e titulação com formaldeído, respectivamente. Para a variedade Cabernet Sauvignon, os valores de nitrogênio total foram: na floração 1,3 g %; 30 dias após a floração 0,58 %; no vèraison 264,2 mg/L e na colheita 303,7 mg/L. Os valores de nitrogênio amoniacal foram 126,3 mg/L no vèraison e 46,6 mg/L na colheita, enquanto que a quantidade de nitrogênio assimilável foi de 101,0 mg/L e 131,1 mg/L, para o mesmo período. Para a variedade Merlot, a quantidade de nitrogênio total foi de 1,24 g % na floração; 0,64 g % 30 DAF; 209,4 mg/L no vèraison e 327,8 mg/L na colheita. Para o nitrogênio amoniacal foram encontrados 86,3 e 25,5 mg/L para vèraison e colheita, respectivamente, enquanto que a quantidade de nitrogênio assimilável foi de 67,0 e 86,0 mg/L, para o mesmo período. Já para a variedade Pinot noir, as quantidades de nitrogênio total foram: 1,65 e 0,57 g % na floração e 30 DAF, respectivamente; 95,3 mg/L no vèraison e 140,9 mg/L na colheita. Para o nitrogênio amoniacal, os valores foram de 36,0 e 18,1 mg/L no vèraison e na colheita, nesta ordem, enquanto que, para o nitrogênio assimilável a quantidade foi de 56,0 e 63,3 mg/L para o mesmo período de coleta. O comportamento das três variedades foi semelhante durante as diferentes fases do ciclo vegetativo e na fermentação, entretanto, as menores quantidades de nitrogênio total no momento da colheita, para a variedade Pinot noir nos levam a sugerir uma adubação nitrogenada no período entre 30 DAF e o vèraison .

Abstract Demographic history and selection affect patterns of genetic diversity in nature. Timing of growth, reproduction and dormancy are important traits targeted by natural selection, because they are crucial for survival of plants growing in boreal and temperate climates, as reproduction must occur when conditions are favorable and in outcrossing plants it must be synchronized to assure pollination. In addition to adaptation to local environments, evolutionarily diverged populations may contain genomic incompatibilities that result in sterile hybrids in crosses between populations. In several plant families within population crosses can also lead to male sterile progeny, because of conflict between maternally and bi-parentally inherited genomes. In this thesis I used DNA-sequence data to estimate the demographic history of nine Arabidopsis lyrata populations and present genetic variation in some key flowering time genes, evolution of which natural selection has shaped. By crossing experiments I explored genetics of reproductive fitness in hybrids between divergent populations. I found that local climatic conditions have resulted in directional selection in addition to the demographic effects of bottlenecks during colonization events. Flowering time genes have reduced diversity compared to reference loci, which indicates selective sweeps. Selection on nucleotide variation in flowering time genes was found in Scandinavian and Icelandic populations that can be explained by selective sweeps at flowering genes when these populations colonized northern habitats after the last glacial maximum. Cryptic cytoplasmic male sterility was found in a Norwegian population, for which North Carolinian population did not have fertility restorers. It was confirmed that there is only one fertility restorer locus, the genomic location of which was mapped to a 600 kb interval at the top of chromosome two. / Tiivistelmä Populaatioiden levittäytymishistoria ja luonnonvalinta vaikuttavat geneettiseen monimuotoisuuteen ja sen vaihteluun genomin eri osissa. Kukkimisen ja kasvun päättämisen ajoitus ovat tärkeitä luonnonvalinnan kohteena olevia ominaisuuksia, sillä ne ovat välttämättömiä kasvien selviytymiselle lauhkeissa ja pohjoisissa ilmastoissa. Paikallisiin olosuhteisiin sopeutumisen lisäksi populaatioiden erilaistuminen voi johtaa genomisiin yhteensopimattomuuksiin, joiden vuoksi populaatioiden väliset risteymät ovat lisääntymiskyvyttömiä. Monilla kasvisuvuilla myös populaation sisäiset risteytykset voivat johtaa koirassteriileihin jälkeläisiin johtuen konfliktista vain äidin puolelta ja molemmilta vanhemmilta periytyvien genomien välillä. Tässä väitöskirjassa selvitän DNA-sekvenssimuunteluun perustuen yhdeksän idänpitkäpalkopopulaation demografista eli levittäymis- ja populaatiorakennehistoriaa sekä luonnonvalinnan osuutta kukkimisaikaan vaikuttavien geenien evoluutiossa. Risteytyskokeiden avulla tutkin erilaistuneiden populaatioiden risteymäjälkeläisiä selvittääkseni niiden lisääntymiskelpoisuutta ja siihen vaikuttavia geenejä. Geneettinen muuntelu kukkimisgeeneissä oli vähäisempää kuin vertailugeeneissä, joka on merkki kukkimisgeeneihin kohdistuneesta suuntaavasta valinnasta. Kukkimisgeeneihin kohdistuvaa valintaa löytyi eniten skandinaavisista ja islantilaisesta populaatiosta, mikä on selitettävissä niihin kohdistuneella suuntavalla valinnalla aikana, jolloin kasvit levittäytyivät jääkauden jälkeen pohjoisiin elinympäristöihin. Norjalaisesta populaatiosta löytyi piilevä sytoplasminen koirassteriliteetti, jolle Pohjois-Carolinan populaatiolla ei ollut hedelmällisyyden palauttavia geenejä. Tutkimus vahvisti, että hedelmällisyyden palauttaa yksi geeni, joka sijaitsee 600 000 emäsparin kokoisella alueella kromosomin kaksi alkupäässä.

Abstract The timing growth and reproduction are critical to the fitness of plants and animals. The timing also has an important role in local adaptation. Locally adapted plants may have different responses to photoperiod and other environmental cues and genes or alleles behind underlying differences may differ between populations. The molecular genetics and physiology of flowering of the plant molecular biology model organism Arabidopsis thaliana is being intensively studied, and this offers a good opportunity to study the genetic basis of flowering time variation in related non-model species. The closely related perennial species Arabidopsis lyrata provides an interesting comparison to A. thaliana because of its different ecology, mating system and life history. The influence of sampling designs on clustering methods was analyzed using simulations and microsatellite data in the selfing A. thaliana. It was found that sample size has a large effect on the resulting number of clusters and sampling too few individuals per locality could lead to a severe underestimation of the real number of subpopulations. Patterns of sequence variation in flowering time genes and association between polymorphisms at FRI (and FLC) and flowering time was studied in A. thaliana and in A. lyrata to find out whether the genes were responsible for flowering time differences between and within natural populations. In A. thaliana there was no significant association between polymorphisms at FLC and FRI and flowering time. In A. lyrata the FRI gene was polymorphic for an indel associated with flowering time variation within two Northern European populations, suggesting that the indel (or a linked polymorphism) was involved in flowering time variation. However, FRI did not explain the flowering time differences between A. lyrata populations, and other loci must be involved. Patterns of diversity and divergence at flowering time related loci were compared against a set of random reference loci to examine the roles of selection and demography. Sequence variation in the studied A. lyrata populations departed from the standard neutral equilibrium model and it has been influenced by recent historical events, most likely bottlenecks. The level of silent and synonymous polymorphisms in flowering time genes was highly reduced and this can be likely explained by selective sweeps at flowering time genes. / Tiivistelmä Kasveilla kukkimisen ajoittaminen suotuisaan ajankohtaan on hyvin tärkeää suvullisen lisääntymisen kannalta. Kukkimisen oikealla ajoituksella on myös tärkeä rooli kasvien sopeutumisessa paikallisiin olosuhteisiin. Kukkimisaikamuunteluun vaikuttavat useimmiten lukuisat geenit sekä ympäristötekijät, jotka voivat vaihdella alueellisesti ja populaatioiden välillä. Vaikka kukkimiseen ja kukkimisaikaan vaikuttavia tekijöitä tunnetaan jo hyvin, luonnonpopulaatioiden muuntelun ja paikallisen sopeutumisen geneettinen tausta on huonommin tunnettu. Väitöstutkimus keskittyy Arabidopsis-populaatioiden paikalliseen sopeutumiseen tarkastelemalla kukkimisajan muuntelua ja siihen vaikuttavia geeneettisiä tekijöitä. Tutkimuksessa käytetyt geneettiset aineistot perustuvat osin neutraaleihin merkkigeeneihin (mikrosatelliittimuunteluun), ja osin sekvenssien nukleotidimuunteluun. Väitöstutkimuksessa on simulointien avulla selvitetty populaatiosta analysoitavien yksilöiden lukumäärän merkitystä populaatiorakenteen selvittämisessä itsesiittoisella lituruoholla (Arabidopsis thaliana). Tulosten mukaan on hyvä analysoida useampia yksilöitä paikallisista populaatioista, sillä liian pienet otoskoot voivat johtaa ryhmien määrän aliarvioimiseen. Koalesenssisimulaatiot osoittavat idänpitkäpalon (Arabidopsis lyrata) populaatioiden poikkeavan tasapainotilasta ja populaatioissa tapahtuneen populaatiokoon muutoksia (ns. pullonkaulailmiö). Tutkimuksessa havaittiin sekvenssimuuntelun olevan alhaisempaa kukkimisaikageeneissä kuin referenssigeeneissä todennäköisesti positiivisen valinnan vaikutuksesta. Tutkimuksessa todettiin, että FRI geenissä tapahtuneet mutaatiot ovat kahdessa tutkitussa lajissa erilaisia luonteeltaan, mutta geenillä on kuitenkin samanlainen rooli kukkimisajan määräämisessä. Assosiaatiokokeissa lituruoholla ei Pohjois-Euroopan populaatioissa löydetty merkitsevää assosiaatiota FRI geenin ja kukkimisajan välillä, kun puolestaa idänpitkäpalolla FRI vaikutti kukkimisaikamuunteluun kahdessa pohjoisessa populaatiossa.

Au vignoble, des nuits froides peuvent se produire pendant la floraison et en particulier au moment de la méiose ovulaire dans les fleurs. La vigne est particulièrement vulnérable puisque la méiose ovulaire se produit lors de la transition du métabolisme de la plante d'un état hétérotrophe à un état autotrophe. Bien que la feuille soit l'organe photosynthétique principal, la jeune inflorescence de vigne possède un statut particulier et participe activement à l'effort reproducteur en exportant la majorité du carbone qu'elle assimile, permettant ainsi le développement des feuilles. Par conséquent, le métabolisme carboné de l'inflorescence lors du développement reproducteur peut être impliqué dans le futur rendement. Chez la vigne, le phénomène de coulure, propre à chaque cépage, peut engendrer des pertes de rendement importantes lorsque la plante est exposée à un stress. Le Pinot noir (PN) est considéré comme un cépage relativement « résistant » à la coulure alors que le taux d'abscission chez le Gewurztraminer (GW) augmente considérablement lors de conditions climatiques défavorables. Chez le PN, l'inflorescence effectue une photosynthèse inférieure et une respiration de nuit supérieure à celle de la feuille. L'activité et la régulation des deux photosystèmes sont très différentes entre ces deux organes lors des premiers stades de développement et les activités des deux photosystèmes sont supérieures au niveau de l'inflorescence. Néanmoins, la protection de la chaîne photosynthétique contre l'excès d'énergie est plus efficace dans la feuille. Contrairement à la feuille, l'activité photosynthétique de l'inflorescence évolue au cours de son développement. En effet, l'activité de la chaîne photosynthétique ainsi que la photosynthèse nette diminuent progressivement au cours de la floraison et le flux cyclique des électrons se met en place pour être finalement supérieur à celui de la feuille. L'activation de ce flux peut alors permettre une synthèse accrue d'ATP, une protection de la chaîne photosynthétique contre les dommages provoqués par un excès d'énergie ou encore la réparation des photosystèmes. Lorsque la nuit froide survient lors de la méiose ovulaire, le métabolisme carboné de l'inflorescence de PN est différemment modifié selon l'intensité du stress. Ainsi, après une nuit à 4°C, la modification de l'activité photosynthétique de l'inflorescence est due à des limitations de nature non-stomatique alors qu'après une nuit à 0°C, cette modification est due à des limitations de nature stomatique. Une nuit à -3°C altère profondément l'activité photosynthétique de l'inflorescence. Ces nuits froides induisent également une accumulation de glucides. Lors du développement floral en conditions optimales, le PN et le GW présentent une activité photosynthétique et un métabolisme carboné différents. La régulation des flux linéaire et cyclique des électrons est également différente. Ce dernier semble avoir une fonction différente chez ces deux cépages avec notamment une possible implication dans la réparation du PSII et/ou dans une synthèse d'ATP accrue à la fin du processus de floraison chez le PN. La chaîne photosynthétique du GW semble mieux protégée ce qui peut expliquer le rendement supérieur de ce cépage en conditions optimales. Néanmoins, l'exposition à une nuit froide entraine des modifications différentes de l'activité de l'inflorescence chez ces cépages avec une perturbation plus importante chez le GW. En effet, chez ce cépage, seule la photosynthèse nette est perturbée suite à la nuit froide alors que chez le PN, les processus de photosynthèse et de respiration sont modifiés. L'activité de la chaîne photosynthétique ainsi que l'activité métabolique de l'inflorescence de GW est également davantage affectée. De manière intéressante, nos résultats suggèrent que ces différentes perturbations de l'activité de l'inflorescence sont dues à des régulations différentes. / In the vineyard, cold night can occur during flowering and particularly at time of female meiosis in flowers. In grapevine, stress vulnerability is enhanced because female meiosis occurs when the whole plant physiology is switching its carbon nutrition from mobilization of wood reserves to photosynthesis in the leaves. Nevertheless, although leaf is the major photosynthetic organ, in grapevine, the young inflorescence has a particular status and takes part in the reproductive effort by exporting the majority of assimilated carbon, allowing in particular the leaves development. Consequently, the inflorescence metabolism during this phase can ultimately determines yield. In grapevine, coulure phenomenon, differing according to the cultivar, can generate important yield losses when a stress occurs. Pinot noir (PN) is considered as a cultivar relatively “resistant” to coulure phenomenon whereas Gewurztraminer (GW) abscission rate considerably increases under environmental stress.In PN, inflorescence performs a lower photosynthesis and a higher dark respiration than leaves. Functioning and regulation of PSI and PSII are very different between inflorescence and leaf during the first developmental stages and activities of these photosystems are higher in the inflorescence. Nevertheless, the photosynthetic chain against excess energy is more efficient in the leaf. Contrary to the leaf, the inflorescence photosynthetic activity evolves during the floral development. Indeed, photosynthetic chain activity and net photosynthesis progressively decrease and the cyclic electron flow appears and is higher than in leaf. This activation could provide ATP, protection against photodamage or repair of the photosystems.When cold night occurs at the female meiosis stage, carbohydrate metabolism of the PN inflorescence is differently modified according to the intensity of the cold stress. At 4°C, photosynthesis in the inflorescence is impaired through non-stomatal limitations, whereas at 0°C it is affected through stomatal limitations. A freezing night (-3°C) severely deregulates photosynthesis in the inflorescence. Cold nights also induce accumulation of sugars.Comparing PN and GW, different photosynthetic activity and carbohydrate metabolism have been showed during the floral development under optimal conditions. Regulations of the linear and cyclic electron flow are also different and the cyclic electron flow seems to have a different aim with particularly an implication in the recovery of PSII and ATP synthesis at the end of the flowering process in PN. GW could have higher protection of the photosynthetic chain and consequently gets a higher yield under optimal conditions. Nevertheless, chilling night impacts differently the activity of the inflorescences of both cultivars with higher modification in GW inflorescence. Indeed, in this cultivar, only the net photosynthesis is altered whereas in PN, both net photosynthesis and respiration processes are modified. The photosynthetic chain activity and metabolical activity of the inflorescence are also more affected by the cold night in GW. Interestingly, our results suggest that the different fluctuation of the inflorescence activities as response to the chilled night is due to different regulations.

Made available in DSpace on 2016-01-26T18:56:26Z (GMT). No. of bitstreams: 1 Vivian Pupo de Oliveira Machado.pdf: 408979 bytes, checksum: 1346e7d9172ff64c6b220a5af3321fbc (MD5) Previous issue date: 2012-12-14 / Calendula officinalis L. (Asteraceae), known as calendula or marigold, is an annual plant and is widely used worldwide as medicinal and ornamental plant. The objective of this work was to evaluate the effect of biostimulant Stimulate®, applied by foliar spray, on the development, in the production of flowers and the content flavonoids in marigold. The experiment was conducted in greenhouse conditions, in Avaré-SP. Seedlings were obtained from commercial seed marigold (Calendula officinalis L., cv. Dobrada Sortida), and the experiment was conducted in plastic pots containing a mixture of organic substrate, loam and sand (ratio 1:1:1). Treatments consisted of different doses of the product Stimulate®, applied by foliar spray, as follow: T1= 0 (distilled water); T2= 3 mL L-1; T3= 6 mL L-1; T4= 9 mL L-1; T5= 12 mL L-1 and T6= 15 mL L-1, applied after 20 days of transplanting the seedlings to pots, carrying out 10 consecutive applications of the product, in the early-morning hours. Biometric evaluations of plants growth were performed at 30, 60 and 90 days after transplanting (height, number of leaves, dry weight of shoot and root) and during the reproductive phase (number of flowers, fresh and dry weight of flowers and content of flavonoids). The experimental design was completely randomized, with 6 treatment and 8 replicates in each treatment, a total of 48 pots. Data were tabulated and submitted to analysis of variance and regression analysis, observing the behavior of the variables according to Stimulate® doses Applying Stimulate® in marigold by foliar spray was not effective in increasing the vegetative growth and total flavonoid content in flowers. In relation to flowering, the Stimulate® application may be used as efficient management technique to provide an increased production of flowers per plant. / Calendula officinalis L. (Asteraceae), conhecida como calêndula ou malmequer, é uma planta anual e é amplamente utilizada em todo o mundo como planta medicinal e ornamental. O objetivo deste trabalho foi avaliar o efeito do bioestimulante Stimulate®, aplicado via pulverização foliar, no desenvolvimento, na produção de inflorescências e no teor de flavonoides em calêndula. O experimento foi instalado em condições de casa de vegetação, no município de Avaré-SP. As mudas foram obtidas a partir de sementes comerciais de calêndula (Calendula officinalis L., cv. Dobrada Sortida), e o experimento foi conduzido em vasos plásticos contendo uma mistura de substrato orgânico, terra argilosa e areia (proporção 1:1:1). Os tratamentos consistiram de diferentes doses do produto Stimulate®, aplicadas via pulverização foliar, a saber: T1= 0 (água destilada); T2= 3 mL L-1; T3= 6 mL L-1; T4= 9 mL L-1; T5= 12 mL L-1 e T6= 15 mL L-1, aplicadas após 20 dias do transplantio das mudas para os vasos, realizando-se 10 aplicações consecutivas do produto, nas primeiras horas da manhã. Foram realizadas avaliações biométricas de crescimento das plantas (altura, número de folhas, massa seca de parte aérea e raiz; aos 30, 60 e 90 dias após transplantio) e avaliações durante a fase reprodutiva (número de capítulos florais, massa seca e fresca dos capítulos florais e teor de flavonoides). O delineamento experimental foi inteiramente casualizado, com 6 tratamentos e 8 repetições em cada tratamento, num total de 48 vasos. Os dados obtidos foram tabulados e submetidos à análise de variância e análise de regressão, observando-se comportamento das variáveis em função das doses de Stimulate®. A aplicação de Stimulate® em calêndula via pulverização foliar não foi eficiente em aumentar o crescimento vegetativo das plantas e o teor de flavonoides totais presente nas inflorescências. Em relação ao florescimento, a utilização de Stimulate® pode ser indicada como técnica de manejo eficiente em proporcionar um aumento da produção de inflorescências por planta.

Made available in DSpace on 2016-07-18T17:51:10Z (GMT). No. of bitstreams: 1 Vivian Pupo de Oliveira Machado.pdf: 408979 bytes, checksum: 1346e7d9172ff64c6b220a5af3321fbc (MD5) Previous issue date: 2012-12-14 / Calendula officinalis L. (Asteraceae), known as calendula or marigold, is an annual plant and is widely used worldwide as medicinal and ornamental plant. The objective of this work was to evaluate the effect of biostimulant Stimulate®, applied by foliar spray, on the development, in the production of flowers and the content flavonoids in marigold. The experiment was conducted in greenhouse conditions, in Avaré-SP. Seedlings were obtained from commercial seed marigold (Calendula officinalis L., cv. Dobrada Sortida), and the experiment was conducted in plastic pots containing a mixture of organic substrate, loam and sand (ratio 1:1:1). Treatments consisted of different doses of the product Stimulate®, applied by foliar spray, as follow: T1= 0 (distilled water); T2= 3 mL L-1; T3= 6 mL L-1; T4= 9 mL L-1; T5= 12 mL L-1 and T6= 15 mL L-1, applied after 20 days of transplanting the seedlings to pots, carrying out 10 consecutive applications of the product, in the early-morning hours. Biometric evaluations of plants growth were performed at 30, 60 and 90 days after transplanting (height, number of leaves, dry weight of shoot and root) and during the reproductive phase (number of flowers, fresh and dry weight of flowers and content of flavonoids). The experimental design was completely randomized, with 6 treatment and 8 replicates in each treatment, a total of 48 pots. Data were tabulated and submitted to analysis of variance and regression analysis, observing the behavior of the variables according to Stimulate® doses Applying Stimulate® in marigold by foliar spray was not effective in increasing the vegetative growth and total flavonoid content in flowers. In relation to flowering, the Stimulate® application may be used as efficient management technique to provide an increased production of flowers per plant. / Calendula officinalis L. (Asteraceae), conhecida como calêndula ou malmequer, é uma planta anual e é amplamente utilizada em todo o mundo como planta medicinal e ornamental. O objetivo deste trabalho foi avaliar o efeito do bioestimulante Stimulate®, aplicado via pulverização foliar, no desenvolvimento, na produção de inflorescências e no teor de flavonoides em calêndula. O experimento foi instalado em condições de casa de vegetação, no município de Avaré-SP. As mudas foram obtidas a partir de sementes comerciais de calêndula (Calendula officinalis L., cv. Dobrada Sortida), e o experimento foi conduzido em vasos plásticos contendo uma mistura de substrato orgânico, terra argilosa e areia (proporção 1:1:1). Os tratamentos consistiram de diferentes doses do produto Stimulate®, aplicadas via pulverização foliar, a saber: T1= 0 (água destilada); T2= 3 mL L-1; T3= 6 mL L-1; T4= 9 mL L-1; T5= 12 mL L-1 e T6= 15 mL L-1, aplicadas após 20 dias do transplantio das mudas para os vasos, realizando-se 10 aplicações consecutivas do produto, nas primeiras horas da manhã. Foram realizadas avaliações biométricas de crescimento das plantas (altura, número de folhas, massa seca de parte aérea e raiz; aos 30, 60 e 90 dias após transplantio) e avaliações durante a fase reprodutiva (número de capítulos florais, massa seca e fresca dos capítulos florais e teor de flavonoides). O delineamento experimental foi inteiramente casualizado, com 6 tratamentos e 8 repetições em cada tratamento, num total de 48 vasos. Os dados obtidos foram tabulados e submetidos à análise de variância e análise de regressão, observando-se comportamento das variáveis em função das doses de Stimulate®. A aplicação de Stimulate® em calêndula via pulverização foliar não foi eficiente em aumentar o crescimento vegetativo das plantas e o teor de flavonoides totais presente nas inflorescências. Em relação ao florescimento, a utilização de Stimulate® pode ser indicada como técnica de manejo eficiente em proporcionar um aumento da produção de inflorescências por planta.

M.Sc.(Agric) / Department of Horticultural Sciences

<div>Maize (Zea mays L.) is one of the most important crops worldwide for its critical importance in agriculture, economic stability, and food security. Many agricultural research and commercial breeding programs target the efficiency of this crop, seeking to increase productivity with fewer inputs and becoming more environmentally sustainable and resistant to impacts of climate and other external factors. For the purpose of analyzing the performance of the new varieties and management strategies, accurate and constant monitoring is crucial and yet, still performed mostly manually, becoming labor-intensive, time-consuming, and costly.<br></div><div>Flowering is one of the most important stages for maize, and many other grain crops, requiring close attention during this period. Any physical or biological negative impact in the tassel, as a reproductive organ, can have significant consequences to the overall grain development, resulting in production losses. Remote sensing observation technologies are currently seeking to close the gap in phenotyping in monitoring the development of the plants’ geometric structure and chemistry-related responses over the growth and reproductive cycle.</div><div>For this thesis, remotely sensed hyperspectral imagery were collected, processed and, explored to detect tassels in maize crops. The data were acquired in both a controlled facility using an imaging conveyor, and from the fields using a PhenoRover (wheel-based platform) and a low altitude UAV. Two pixel-based classification experiments were performed on the original hyperspectral imagery (HSI) using Spectral Angle Mapper (SAM) and Support Vector Machine (SVM) supervised classifiers. Feature reduction methods, including Principal Component Analysis (PCA), Locally Linear Embedding (LLE), and Isometric Feature Mapping (Isomap) were also investigated, both to identify features for annotating the reference data and in conjunction with classification.</div><div>Collecting the data from different systems allowed the identification of strengths and weaknesses for each system and the associated tradeoffs. The controlled facility allowed stable lighting and very high spatial and spectral resolution, although it lacks on supplying information about the plants’ interactions in field conditions. Contrarily, the in-field data from the PhenoRover </div><div>and the UAV exposed the complications related to the plant’s density within the plots and the variability in the lighting conditions due to long times of data collection required. The experiments implemented in this study successfully classified pixels as tassels for all images, performing better with higher spatial resolution and in the controlled environment. For the SAM experiment, nonlinear feature extraction via Isomap was necessary to achieve good results, although at a significant computational expense. Dimension reduction did not improve results for the SVM classifier.</div>