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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.
11

Altera??es fisiol?gicas e metab?licas em Hyptis fruticosa Salzm. ex. Beth e Ocimum gratissimum L. sob diferentes regimes h?dricos

Co?lho, Maria Reis Valois 28 March 2014 (has links)
Submitted by Natalie Mendes (nataliermendes@gmail.com) on 2015-07-28T01:01:50Z No. of bitstreams: 1 Disserta??o_RGV_Maria Reis.pdf: 1106415 bytes, checksum: 7034ec4c42920fa1bf7a9238be4d7eb7 (MD5) / Made available in DSpace on 2015-07-28T01:01:50Z (GMT). No. of bitstreams: 1 Disserta??o_RGV_Maria Reis.pdf: 1106415 bytes, checksum: 7034ec4c42920fa1bf7a9238be4d7eb7 (MD5) Previous issue date: 2014-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Hyptis fruticosa Salzm. Ex. Benth and Ocimum gratissimum Lindi are species from lamiaceae family of great medicinal importance, notwithstanding, they have been goals of few studies related to the cultivation techniques. Therefore, the study?s goal was to evaluate the behavior and tolerance of plants of H. fruticosa and O. gratissimum cultivated in vases submitted to different levels of evapotranspired water reposition during thirteen days (H. fruticosa) and nine days (O. gratissimum). The experiment was made in greenhouse under randomized complete block design with four treatments (100, 75, 50 and 0% of evapotranspired water reposition). It was verified that there were not any significant difference of total dry mass and leaf area among the treatments in the species H. fruticosa and O. gratissimum. Both of them presented the lowest values of relative water content, water potential, chlorophylls and carotenoids in the water reposition 0% treatment. In O. gratissimum, there was the decrease in net assimilation of carbon, stomatal conductance and transpiration with the water deficit increase, but the CO2 inside concentration was higher in the water reposition 0% treatment. The two species presented amino acid accumulation, proline, soluble proteins and soluble carbohydrate according to the water deficit increase. The essential oil content increased with the water availability increment in O. gratissimum, but it did not present the significant difference among the treatments in H. fruticosa. O. gratissimum revealed itself more sensitive and H. fruticosa more tolerant to the water deficiency. / Hyptis fruticosa Salzm. ex. Benth e Ocimum gratissimum Lindl. s?o esp?cies da fam?lia lamiaceae de grande import?ncia medicinal, no entanto, t?m sido objetos de poucos estudos relacionados ?s t?cnicas de cultivo. Assim, o objetivo deste trabalho foi avaliar o comportamento e toler?ncia de plantas de H. fruticosa e O. gratissimum cultivadas em vasos submetidas a diferentes n?veis de reposi??o de ?gua evapotranspirada durante o per?odo de treze dias (H. fruticosa) e nove dias (O. gratissimum). O experimento foi realizado em telado sob delineamento em blocos casualizados com quatro tratamentos (100, 75, 50 e 0% de reposi??o de ?gua evapotranspirada). Verificou-se que n?o houve diferen?as significativas da massa seca total e ?rea foliar entre os tratamentos nas esp?cies H. fruticosa e O. gratissimum. As duas esp?cies apresentaram os menores valores de teor relativo de ?gua, potencial h?drico, clorofilas e caroten?ides no tratamento 0% de reposi??o de ?gua. Em O. gratissimum, houve redu??o da assimila??o l?quida de carbono, condut?ncia estom?tica e transpira??o com o aumento do d?ficit h?drico, por?m a concentra??o interna de CO2 foi superior no tratamento 0% de reposi??o de ?gua. As duas esp?cies apresentaram ac?mulo de amino?cidos livres, prolina, prote?nas sol?veis e carboidratos sol?veis de acordo com o aumento do d?ficit h?drico. O teor de ?leo essencial aumentou com o incremento da disponibilidade h?drica em O. gratissimum, mas n?o apresentou diferen?a significativa entre os tratamentos em H. fruticosa. A esp?cie O. gratissimum mostrou-se mais sens?vel e H. fruticosa mais tolerante ? defici?ncia h?drica.
12

Tolerância à dessecação em Pleurostima purpurea (Velloziaceae): trocas gasosas, pigmentos fotossintéticos e conteúdo relativo de água foliar / Desiccation tolerance in Pleurostima purpurea (Velloziaceae): gas exchanges, photosynthetic pigments and leaf relative water content

Saulo de Tarso Aidar 07 December 2005 (has links)
Pleurostima purpurea (Velloziaceae) é uma espécie rupícola encontrada em afloramentos rochosos do estado do Rio de Janeiro, sudeste do Brasil. Por apresentar notável capacidade de tolerar a dessecação vegetativa, este estudo teve o intuito de esclarecer detalhes sobre a estratégia ecofisiológica utilizada por tais plantas frente à desidratação do ambiente e as vantagens associadas ao processo. Para tanto foi analisada a dinâmica de trocas gasosas, o conteúdo de pigmentos fotossintéticos e o conteúdo relativo de água de tecidos foliares durante os processos de dessecação e reidratação de indivíduos adultos cultivados. Comportaram-se como homeohídricas típicas economizadoras de água sob condição de seca moderada que, quando agravada, assumiram o comportamento de pecilohídricas e peciloclorófilas. A suspensão da irrigação provocou o fechamento estomático sob conteúdo relativo de água foliar acima de 90%, levando a restrições sobre a transpiração e assimilação líquida de carbono até o estabelecimento da anabiose. Durante este processo, houve um atraso na diminuição do CRAfoliar em relação ao CRAplanta-solo. A degradação das clorofilas acompanhou a diminuição do CRAfoliar, o qual alcançou o valor médio mínimo de 17% sem incorrer na abscisão das folhas, enquanto sua resíntese somente se iniciou após a total reidratação dos mesmos tecidos. Durante todo este processo o conteúdo de carotenóides manteve-se estável. 12 horas de reidratação do solo de cultivo foram suficientes para a retomada respiratória. Um balanço positivo de CO2 foi observado a partir da 36ª hora de reidratação quando o grau de abertura estomática passou a ser maior do que o observado para o grupo controle. Comparando-se com as condições iniciais, 84 horas de reidratação foram suficientes para a recuperação fotossintética mesmo com uma recuperação apenas parcial do conteúdo de clorofilas. Assim como os tecidos foliares, suas raízes também devem ser tolerantes à dessecação. / Pleurostima purpurea (Velloziaceae), a rupicolous flowering species found in rock outcrops in Rio de Janeiro state, southeastern Brazil, show notable capacity to endure vegetative desiccation. This study had the intent to show more details about the ecophysiological strategy used by these plants facing a drying ambient and the advantages associated with the process. For this, it was analised the gas exchanges, photosynthetic pigments content, and relative water content of leaf tissues during desiccation and rehydration of cultivated individuals. They behaved typicaly as homeohydrics water savers under moderated drought condition that, when aggravated, prosecute with poikilohydric and poikilochlorophyllous behavior. After watering suspension, stomatic closing was observed under a relative leaf water content up to 90% that resulted in gas exchanges restrictions until the anabiosis. During this process, it was observed a delay in the leaf relative water content (RWCleaf) decrease comparing to the plant-soil relative water content (RWCplant-soil). The chlorophylls degradation acompanished the RWCleaf decrease, which achived the minimum average value of 17% without incur in leaves abscission, while its resynthesis just begun after the full leaves rehydration. During all of this process, the carotenoids content remained stable. Twelve hours of soil rehydration were sufficient for the respiration retake. A positive carbon balance was observed since the 36th hour of rehydration, when the degree of stomatic opening became bigger than that observed for the control group. Comparing with inicial conditions, 84 hours of rehydration were sufficient to photosynthetic recovery, even just with a parcial recovery of chlorophyll content. As well as the leaf tissues, its roots might be desiccation tolerants.
13

Estresse pela aplicação de radiação UV-C e o déficit hídrico em genótipos de tomate Micro-Tom / Stress by the application of UV-C and water déficit in genotypes of Micro-Tom tomato plants

Hüther, Cristina Moll 28 March 2014 (has links)
Made available in DSpace on 2014-08-20T13:59:08Z (GMT). No. of bitstreams: 1 tese_cristina_huther.pdf: 966830 bytes, checksum: 5ef15a4c44099ced96bf589355808571 (MD5) Previous issue date: 2014-03-28 / The objectives of this study were: a. to compare growth and yield components of Micro-Tom tomato plants with wild plants and transformed plants for different levels of MT-sHSP23.6 expression (mitochondrial small heat shock proteins); b. to verify damages caused by UV-C application to photosynthetic activity, in the vegetative and reproductive stages, with the same genotypes previously described; c. to compare the effects of water deficit on photosynthetic activity in Micro-Tom tomato plants with the genotypes reported, in the period of floral induction. The first experiment was carried out in growth chambers, under controlled conditions. The analyses were performed at regular time intervals of 21 days. Collections started on 21st day after the transplant, a total of six collections. Leaf area, dry weight of the plants parts, and the number of green and red fruits were determined. From the results obtained we verified that the genetic transformation of this variety did not interfere significantly with these plants growth. In the second experiment that aimed to evaluate the effect of application of UV-C radiation, two trials were performed; the plants were grown in a green house, under controlled temperature and humidity. In the first trial the application of UV-C radiation was performed only once, when the plants were in vegetative stage. In the second trial the plants were exposed to two doses of UV-C radiation, with an interval of ten days, the application began when the plants were starting the reproductive stage. The application lasted two minutes with a dose of 0,5kJ.m-2. Chlorophyll index, chlorophyll a fluorescence, and gas exchanges were evaluated. At the first trial, the evaluations were performed at 16, 64, 168, and 336 hours after the application of the radiation, and in the second trial at 16, 64, and at 168 hours after first application, with the same interval after the second application of radiation. From the results we observed that the genotypes showed different behaviors in relation to the data of transient fluorescence. However, the net assimilation rate was more affected in the transformed genotypes, with greater intensity in the second trial, especially after the second application. We noticed that in both trials genetic transformation did not contributed significantly to provide better performance under these experimental conditions. In the third trial the plants were grown in a growth chamber. Fortyfour days after sowing, in floral induction period, they were submitted to water deficit for five days. Chlorophyll index, chlorophyll a fluorescence, and gas exchanges were evaluated, and at the end of the experiment we made simultaneous analysis of fluorescence decrease, modulated reflection at 820 nm, proline content in the foliar area, and dry matter of plant parts. We could verify that genotype with over-expression of MT-sHSP23.6 was more efficient than the other genotypes in photochemical reactions, allowing that water deficit data were smaller, however it was not possible to identify the relation of the over-expression of these proteins with the parameters of gas exchange. / Este trabalho teve por objetivo: a) comparar o crescimento e componentes de produção de plantas de tomateiro Micro-Tom , com plantas selvagem e plantas transformadas para diferentes níveis de expressão da MT-sHSP23.6 (mitochondrial small heat shock proteins); b) verificar as injúrias causadas pela aplicação UV-C, na atividade fotossintética, no estádio vegetativo e reprodutivo, com os mesmos genótipos descritos anteriormente; c) comparar os efeitos que o déficit hídrico apresenta sobre a atividade fotossintética em plantas de tomate Micro-Tom , no período de indução floral, nos mesmos genótipos relatados. O primeiro experimento foi conduzido em câmaras de crescimento, sob condições controladas. As análises foram realizadas com intervalos regulares de tempo de 21 dias, iniciando as coletas no 21º dia após o transplante e ao total foram realizadas seis coletas. Foram determinadas: área foliar, massa seca das partes das plantas e o número de frutos verdes e vermelhos. Através dos resultados obtidos verificou-se que a transformação genética desta variedade não interferiu de maneira significativano crescimento destas plantas. No segundo experimento, que apresentou objetivo de avaliar o efeito da aplicação da radiação UV-C, foram realizados dois ensaios, sendo queas plantas foram cultivadas em casa de vegetação, com temperatura e umidade controlada. No primeiro ensaio, a aplicação da radiação UV-C foi realizadaapenas uma só vez quando as plantas estavam no estádio vegetativo. No segundo ensaio as plantas foram submetidas a duas doses de radiação UV-C, com intervalo de 10 dias, iniciando a aplicação quando as plantas estavam em inicio de estádio reprodutivo. Aaplicação durou 2 minutos com uma dose de 0,5 kJ.m-2. Foram avaliados: índice de clorofila, fluorescência da clorofila a e trocas gasosas. No primeiro ensaio as avaliações foram realizadas após 16, 64, 168 e 336 horas após a aplicação da radiação, e no segundo as 16, 64 e 168 horas após a primeira aplicação e com o mesmo intervalo após a segunda aplicação da radiação. Por intermédio dos resultados observou-se os genótipos apresentaram comportamentos distintos em relação os dados da fluorescência transiente. Contudo a taxa assimilatória líquida foi mais afetada nos genótipos transformados e com maior intensidade no segundo ensaio, principalmente após a segunda aplicação da radiação UV-C. Dessa forma verificou-se que em ambos os ensaios, a transformação genética não contribuiu de maneira significativa para proporcionar melhor desempenho nessas condições experimentais. No terceiro experimento as plantas foram cultivadas em câmara de crescimento. Quando estas estavam com 44 dias após a semeadura, no período de indução floral, as mesmas foram submetidas ao déficit hídrico por cinco dias. Foram avaliados: índice de clorofila, fluorescência da clorofila a e trocas gasosas e ao final do experimento foram realizadas análises simultâneas da decaída da fluorescência, reflexão modulada a820nm, teor de prolina nas folhas área foliar e massa seca das partes das plantas. Pode-se verificar que o genótipo com superexpressão da MT-sHSP23.6 foi mais eficiente que os demais genótipos nas reações fotoquímicas, permitindo que os dados do déficit hídrico fossem menores, contudo não foi possível evidenciar relação da superexpressão dessa proteína com os parâmetros das trocas gasosas.
14

Respostas ecofisiológicas e bioquímicas do Ocimum basilicum L. cultivado em diferentes níveis hídricos / Reposts ecophysiological and biochemical of the Ocimum Basilicum cultivate under water deficit.

Vargas, Maria Eliane de Oliveira 28 February 2007 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The sustainable development of northern agroecosystems requires, among other factors, the use of species adapted to region the edafoclimtic conditions. Plants able to support water deficits are more indicated, considering to no regular distribution of pluviometric precipitation the high evapotranspiration are characteristic northest region of Brazil. The present work was carried out to determine the ecofisiologic and biochemistry behavoir of three cultivars of basil, Ocimum basilicum L. (Maria Bonita, Mara and Genovese) cultivated under water stress. The ecofisiologics variables were: hidric potential of leaves, photossintesis, transpiration, stomatal conductance; the biochemitry variables were: soluble carbohydrates and proteins, totals cloroplasts, tenor of essential oil and percentage of linalool. The varibles were analyzed in plants with four months of aged, cultivated in 24 vases of 17L, in greenhouse, having two treatments: T0 (control) and T1 (experimental group), with four repetitions. The variables were evaluated at 08:30 to 10:30 hours every two days, during 15 days in October 2005. In base of results it was identifyed that basil presents mechanisms of adaptation under water stress minimizing the water lose. Mara’and Maria Bonita’cultivars presented more adaptaded under water stress in comparison with ‘Genovese’cultivar. In relation to the essential linalool content the three cultivars kept their yield even under water stress. It was observed the geraniol presence in Maria Bonita cultivar. / O desenvolvimento sustentável dos agroecossistemas nordestinos requer, dentre outros fatores, o uso de espécies adaptadas às condições edafomorfoclimáticas da região. Plantas capazes de suportar déficits hídricos são mais indicadas, uma vez que a distribuição irregular da precipitação pluviométrica, aliada a alta evapotranspiração são características do Nordeste brasileiro. O presente trabalho objetiva determinar o comportamento ecofisiológico e análise bioquímica de três cultivares de manjericão, Ocimum basilicum L.(‘Maria Bonita’, ‘Mara’ e ‘Genovese’) quando cultivadas sob estresse hídrico. As variáveis ecofisiológicas foram: potencial hídrico foliar, fotossíntese, transpiração, condutância estomática; e as bioquímicas foram: carboidratos solúveis, proteínas solúveis, cloroplastos totais e teor de óleo essencial e de linalol no óleo essencial. As variáveis ecofisiológicas e bioquímicas foram analisadas quando as plantas apresentavam 4 meses de idade. Cultivadas em 24 vasos de 17 L, em estufa agrícola, sendo 2 tratamentos: T0 (testemunha) e T1 (grupo experimental), com 4 repetições. As variáveis ecofisiológicas foram avaliadas entre 08:30 a 10:30 horas, em dias alternados, durante 15 do mês de outubro de 2005. Com base nos resultados obtidos, constatou-se que o manjericão apresenta mecanismos de adaptação, que sob condição de estresse hídrico, diminuem as perdas de água. As cultivares ‘Mara’ e ‘Maria Bonita’ apresentaram adaptadas às condições de estresse hídrico quando comparadas com a cultivar ‘Genovese’. Em relação ao teor linalol as três cultivares mantiveram as suas produtividades mesmo sob condição de estresse. Observou-se também, a presença de geraniol no óleo essencial da cultivar Maria Bonita.
15

Développement de modèles physiques pour comprendre la croissance des plantes en environnement de gravité réduite pour des apllications dans les systèmes support-vie / Developing physical models to understand the growth of plants in reduced gravity environments for applications in life-support systems

Poulet, Lucie 11 July 2018 (has links)
Les challenges posés par les missions d’exploration du système solaire sont très différents de ceux de la Station Spatiale Internationale, puisque les distances sont beaucoup plus importantes, limitant la possibilité de ravitaillements réguliers. Les systèmes support-vie basés sur des plantes supérieures et des micro-organismes, comme le projet de l’Agence Spatiale Européenne (ESA) MELiSSA (Micro Ecological Life Support System Alternative) permettront aux équipages d’être autonomes en termes de production de nourriture, revitalisation de l’air et de recyclage d’eau, tout en fermant les cycles de l’eau, de l’oxygène, de l’azote et du carbone, pendant les missions longue durée, et deviendront donc essentiels.La croissance et le développement des plantes et autres organismes biologiques sont fortement influencés par les conditions environnementales (par exemple la gravité, la pression, la température, l’humidité relative, les pressions partielles en O2 et CO2). Pour prédire la croissance des plantes dans ces conditions non-standard, il est crucial de développer des modèles de croissance mécanistiques, permettant une étude multi-échelle des différents phénomènes, ainsi que d’acquérir une compréhension approfondie de tous les processus impliqués dans le développement des plantes en environnement de gravité réduite et d’identifier les lacunes de connaissance.En particulier, les échanges gazeux à la surface de la feuille sont altérés en gravité réduite, ce qui pourrait diminuer la croissance des plantes dans l’espace. Ainsi, nous avons étudié les relations complexes entre convection forcée, niveau de gravité et production de biomasse et avons trouvé que l’inclusion de la gravité comme paramètre dans les modèles d’échanges gazeux des plantes nécessite une description précise des transferts de matière et d’énergie dans la couche limite. Nous avons ajouté un bilan d’énergie au bilan de masse du modèle de croissance de plante déjà existant et cela a ajouté des variations temporelles sur la température de surface des feuilles.Cette variable peut être mesurée à l’aide de caméras infra-rouges et nous avons réalisé une expérience en vol parabolique et cela nous a permis de valider des modèles de transferts gazeux locaux en 0g et 2g, sans ventilation.Enfin, le transport de sève, la croissance racinaire et la sénescence des feuilles doivent être étudiés en conditions de gravité réduite. Cela permettrait de lier notre modèle d’échanges gazeux à la morphologie des plantes et aux allocations de ressources dans une plante et ainsi arriver à un modèle mécanistique complet de la croissance des plantes en environnement de gravité réduite. / Challenges triggered by human space exploration of the solar system are different from those of the International Space Station because distances and time frames are of a different scale, preventing frequent resupplies. Bioregenerative life-support systems based on higher plants and microorganisms, such as the ESA Micro-Ecological Life Support System Alternative (MELiSSA) project will enable crews to be autonomous in food production, air revitalization, and water recycling, while closing cycles for water, oxygen, nitrogen, and carbon, during long-duration missions and will thus become necessary.The growth and development of higher plants and other biological organisms are strongly influenced by environmental conditions (e.g. gravity, pressure, temperature, relative humidity, partial pressure of O2 or CO2). To predict plant growth in these non-standard conditions, it is crucial to develop mechanistic models of plant growth, enabling multi-scale study of different phenomena, as well as gaining thorough understanding on all processes involved in plant development in low gravity environment and identifying knowledge gaps.Especially gas exchanges at the leaf surface are altered in reduced gravity, which could reduce plant growth in space. Thus, we studied the intricate relationships between forced convection, gravity levels and biomass production and found that the inclusion of gravity as a parameter in plant gas exchanges models requires accurate mass and heat transfer descriptions in the boundary layer. We introduced an energy coupling to the already existing mass balance model of plant growth and this introduced time-dependent variations of the leaf surface temperature.This variable can be measured using infra-red cameras and we implemented a parabolic flight experiment, which enabled us to validate local gas transfer models in 0g and 2g without ventilation.Finally, sap transport needs to be studied in reduced gravity environments, along with root absorption and leaf senescence. This would enable to link our gas exchanges model to plant morphology and resources allocations, and achieve a complete mechanistic model of plant growth in low gravity environments.
16

Exploration de la variabilité phénotypique d'Arabidopsis thaliana (L.) Heynh et caractérisation de l'effet d'un déficit hydrique sur la photosynthèse et le contenu glucidique foliaire des écotypes Col-0, Mt-0 et Shahdara / Investigation of Arabidopsis thaliana (L.) Heynh phenotypic variability and characterization of drought stress effects on photosynthesis and leaf sugar content of Col-0, Mt-0 and Shahdara ecotypes

Abadie, Cyril 26 October 2012 (has links)
Compte tenu des changements climatiques annoncés, les végétaux risquent d'être confrontés, dans un proche avenir, à des épisodes de sécheresse sévères de plus en plus fréquents. Afin de prédire l'impact de telles contraintes sur la productivité et le rendement des plantes cultivées, il convient d'étudier l'effet du manque d'eau sur l'activité photosynthétique, le transport et l'accumulation des sucres. Dans un premier temps, la croissance, le développement, la biomasse et la photosynthèse de huit écotypes d'Arabidopsis thaliana ont été caractérisés. Trois de ces écotypes (Col-0, Mt-0 et Shahdara) ont ensuite été soumis à une période de déficit hydrique. Une chute du contenu relatif en eau des rosettes (RWC), de la conductance stomatique (gs) et de l'assimilation nette (AN) a été observée précocement chez Mt-0, écotype initialement caractérisé par une très faible efficience de l'utilisation de l'eau (AN/E). En réponse au stress, l'analyse des courbes AN/Ci de chaque écotype montrait que la limitation stomatique s'accompagne rapidement de limitations métaboliques (baisse de la Vcmax). En fin de stress hydrique, une diminution des réserves en amidon a conduit dans tous les cas à une accumulation de saccharose dans les feuilles. Les expressions des gènes codant les principaux transporteurs foliaires de sucres (polyols, hexoses et saccharose) étaient quant à eux différemment affectés par le manque d'eau. Shahdara, qui est parvenu à conserver un RWC relativement élevé, est l'écotype qui a le mieux toléré la contrainte hydrique. À l'opposé, Mt-0 présentait, en fin de stress, une inhibition de l'AN couplée à des altérations majeures et irréversibles des photosystèmes II (chutes de qP et de Fv/Fm). / Considering the predicted climate changes, plants are likely to face, in the future, severe and frequent droughts. In order to evaluate the impact of such stress on productivity and crop yield, the effect of water shortage on photosynthetic activity, sugar transport and accumulation was investigated. Firstly, growth, development, biomass and photosynthesis of eight Arabidopsis thaliana ecotypes have been characterised. Secondly, three of them (Col-0, Mt-0 and Shahdara) were subjected to drought stress. The relative water content (RWC), the stomatal conductance (gs) and the net assimilation (AN) decreased early in rosette leaves of Mt-0 which was initially characterized by a very low water use efficiency (AN/E). In response to drought, AN/Ci curves analysis for each ecotype showed that stomatal limitation was quickly related with metabolic limitations (lower Vcmax). At the end of the stress, reduced starch content always led to a sucrose accumulation in leaves. The expression of genes encoding the main leaf sugar carriers (polyols, hexoses and sucrose) was differently impaired by the water shortage. Shahdara, that managed to maintain a relatively high RWC, was the most tolerant ecotype to water stress. In contrast, at the end of the stress, Mt-0 exhibited an AN inhibition together with significant and irreversible photosystem II alterations (drop of both qP and Fv/Fm).

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