fotosistemas i y ii pdf file. Quote. Postby Just» Tue Aug 28, am. Looking for fotosistemas i y ii pdf file. Will be grateful for any help! Top. of foliage loss, altered leaf orientation, stomatal closure, and photosystem II downregulation. la regulaci6n del fotosistema a la baja en el PSII, mientras que esta conducta TUCKER, C. J., I. Y. FUNG, C. D. KEELING, AND R. H. GAMMON. of foliage loss, altered leaf orientation, stomatal closure, and photosystem II downregulation. la regulación del fotosistema a la baja en el PSII, mientras que esta conducta TUCKER, C. J., I. Y. FUNG, C. D. KEELING, AND R. H. GAMMON.

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Chlorophyll content was higher in leaves of the defoliated plants, but this did not correlate with a higher photosynthetic efficiency. Plants lacking the main lightharvesting complex retain photosystem II macro-organization.

Revista Facultad Nacional de Agronomía Medellín

This procedure is utilized in fotosistdma majority of wine-producing countries to increase the concentration of various compounds in the fruits, such as phenols, thus giving new characteristics of flavor and aroma to the wine Kemp et al.

Hence, the characterization of PSII behavior is an important tool for researchers to evaluate photosynthetic activity in plants. Compensatory plant-growth as a response to herbivory.

Photosynthetic responses of wheat, Triticum aestivum L. Final production of a crop is affected by the conditions in which it was grown. When leaf area is reduced, photon flow increases towards the plant’s remaining leaves, which can increase leaf temperature and saturate reaction centers due to an excess of light. Leaf removal creates a negative effect by reducing growth rate, but plants possess a fotoslstema threshold to defoliation McNaughton, The chlorophyll content and fluorescence were determined in five-year-old grape plants Vitis vinifera L.

DNA damage and repair in plants.

Nevertheless, in the present study, a reduction was observed in this value, which indicates that defoliation induces a higher degree of stress in Chardonnay grape plants, perhaps due to higher exposure of the remaining leaves to direct radiation, which elevates leaf temperature fotosisfema affects photosynthesis mechanisms. It is evident that a reduction in leaf area modifies the partitioning of excitation energy destined for photochemical and non-photochemical processes, thus directly influencing the photosynthetic process of the plants evaluated.

Bios Scientific Publishers, Oxford. La luz como factor de tipicidad y calidad en el terroir tropical de altitud, el ejemplo de la vid fotosisstema el vino en el Valle del Sol. These four factors frame the potential yield of fotoslstema grapevine in terms of quantity and quality.


fotosistemas i y ii pdf file – PDF Files

Applications of chlorophyll fluorescence can improve crop production strategies: The average value registered for the defoliated plants was 9. Furthermore, it must be noted that secondary metabolites do not only determine wine quality, but they also play oftosistema important role as antioxidants that benefit human health by protecting against oxidative stress caused by highly-reactive free radicals in the body Quijano, This was perhaps due to the fact that herbivorous defoliation induces a quicker response from the plant as a result of the action of insect mandibles on the leaves, thus creating a compensatory response.

Leaves of defoliated plants are generally exposed to higher light intensity and, frequently, fotosistsma modification of light quality, both of which influence the development of photosynthetic capacity Richards, The chlorophyll concentration index CCI was determined. Doctor of Phylosophy thesis. General Subjects 2: In this sense, it is possible that the grape plants of the present study modified their photosynthetic capacity in response to defoliation, raising total chlorophyll content Richards, or diminishing the senescence rate of the remaining leaves Hunter and Visser, Karukstis oi that reductions in maximum quantum efficiency of PSII occur simultaneously with a reduction in net assimilation of CO2, and if this reduction is shown in continuously illuminated leaves, it is possible that the effect is due to photoinhibition.

Plant responses to foliar attack. Higher plants and UV-B radiation: Morphological Asymmetry and chlorophyll fluorescence in Scots pine Pinus sylvestrisresponses to variation in soil k, nutrients and defoliation.

Furthermore, Weis and Berry found that the fotosistems quenching coefficient qP in different species was close to 1 in conditions of low light intensity, but diminished to 0. Contrary to the findings of the present experiment, it is possible for an increase in photon flow to trigger damage in the D1 protein of PSII, which causes fotoxistema notable reduction in F o in tree species exposed to increased radiation, due principally to chronic photoinhibition of PSII Dias and Marenco, This explains the behavior of the defoliated plants in the present study, since a higher exposure to direct radiation after a reduction in leaf number increases photon flow and leaf temperature and finally ftosistema a failure of the photosynthetic system.

The quantification of plant stress in this case caused by defoliation is a useful tool in plant ecophysiology, with which potential photosynthetic behavior and dissipation of absorbed energy can be determined. Trends in Plant Science 3 4: Every two weeks, one of every two recently-emerged leaves was removed from the non-control plants. The present study therefore aimed to evaluate the influence of early partial defoliation on chlorophyll fluorescence in grape plants Vitis vinifera L.


Physiology of plants recovering from defoliation. Responses of Cynoglossum officinale L.


A different result was obtained in Prunus cerasus, fotossitema which the maximum quantum efficiency of PSII, measured seven days after the defoliation event, increased slightly with respect to non-defoliated plants Layne and Flore,possibly due to compensatory photosynthesis, which does not occur immediately but rather has a slow rate of recovery.

The effect of partial defoliation, leaf position and developmental stage of the vine on leaf chlorophyll concentration in relation to the photosynthetic activity and light intensity in the canopy of Vitis vinifera L.

With regards to defoliation, in studies undertaken by Retuerto et al. The value of minimum fluorescence increased by Nevertheless, human actions partially or completely modify the behavior of each factor, thus determining the terroir of the vine’s development Vaudour, ; Quijano, Response of sunflower plants to physical injury.

In this part of the country, it is possible, with good crop management, to obtain two harvests per yy, thanks to the local agroclimatic conditions Almanza et al. On the other hand, Layne and Flore reported a reduction in minimum fluorescence values fotosisyema seven days after defoliation of Prunus cerasus plants exposed to 14 h of daily light.

Advances in Space Research 45 7: Concentration of photosynthetic pigments and chlorophyll fluorescence of Mahogany and Tonka bean under two light environments. Food and Agriculture Organization of the United Nations. It is possible for F o values to increase when there is a slowdown in excitation energy transfer from the light collection system to the reaction center Baker and Rosenqvist,or when there is some type of damage in the PSII reaction centers themselves Vieira et al.

Physiological responses of Prunus cerasus to whole-plant source manipulation. Chlorophyll fluorescence is a widely-used technique for tracking this phenomenon, both in cultivated and wild plants. Photoinhibition in Vitis californica: Energy dissipation as heat Y NPQ showed no significant difference between treatments. Junior-Pam Chlorophyll Fluorometer, operator’s guide.

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