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M. Diaz A. Haag-Kerwer R. Wingfield E. Ball E. Olivares T. E. E. Grams H. Ziegler U. Lüttge 《Trees - Structure and Function》1996,10(6):351-358
Samples of the Clusiaceae generaClusia, Oedematopus andDystovomita were collected at various sites and different altitudes in northern and south-western Venezuela. Analyses of stable isotopes of carbon and hydrogen and of leaf-nitrogen levels were performed on the dried samples. Correlations among these variables, i.e. carbon isotope discrimination (), hydrogen isotope ratio (D) and N-levels, and with altitude were assessed. In the samples, where values of above 15 indicate predominant performance of C3 photosynthesis, there were slight tendencies of increasing , D and N-levels with increasing altitude and of increasing with increasing N. Although these correlations taken separately were not statistically significant, they support each other and indicate increasing transpiration and increased leaf-nutrient supply at increasing altitude. Performance of crassulacean acid metabolism (CAM) in species ofClusia appears to be restricted to altitudes below 1500 m a.s.l. There was a significant negative correlation of with altitude in the samples, where values of below 10 indicated predominant performance of CAM. This suggests that phases II and IV of CAM are progressively suppressed towards the upper altitudinal limit of CAM inClusia in northern Venezuela. It is concluded that among the large number of environmental factors and combinations thereof, which determine the expression of CAM inClusia and trigger C3-CAM transitions in C3/CAM intermediate species, low availability of water is the most important. 相似文献
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Augusto C. Franco Angela Haag-Kerwer Britta Herzog Thorsten E. E. Grams Erika Ball Eduardo A. de Mattos Fabio R. Scarano Suzanne Barreto Maria A. Garcia Andre Mantovani Ulrich Lüttge 《Trees - Structure and Function》1996,10(6):359-365
Sandy plains are characteristic of the coastal region of Brazil. We investigated the diel patterns of changes in organic acid levels, leaf conductance and chlorophylla fluorescence for sun-exposed and shaded plants ofClusia hilariana, one of the dominant woody species in the sandy coastal plains of northern Rio de Janeiro state. Both exposed and shaded plants showed a typical CAM pattern with considerable diel oscillations in organic acid levels. The degradation of both malic and citric acids during the midday stomatal closure period could lead to potential CO2 fixation rates of 28 mol m-2 s-1 in exposed leaves. Moreover, exposed leaves exhibited large increases in total non-photochemical quenching (qN) accompanied by a substantial decrease in effective quantum yield during the course of the day. However, these potential high rates of CO2 fixation and the increases inqn of exposed plants were not enough to maintain the primary electron acceptor of photosystem II (qA) in a low reduction state, similar to that of shaded plants. As a result, there was a moderate increase in the reduction state of qA throughout the day. Most of the decline in photochemical efficiency of exposed leaves ofC. hilariana was reversible, as evidenced by the high levels of pre-dawn potential quantum yields (Fv/Fm) and their rapid recovery after sunset. However, the depletion of the organic acid pool in the afternoon resulted in an accentuated subsequent drop in Fv/Fm, suggesting that prolonged periods of water stress accompanied by high irradiance levels may expose plants ofC. hilariana in unprotected habitats to the danger of photoinhibition. 相似文献
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Martina Bhm R. Lw Angela Haag-Kerwer U. Lüttge Th. Rausch 《Plant biology (Stuttgart, Germany)》1993,106(5):448-453
Understanding the taxonomiy of the tropical genus Clusia (Fam. Clusiaceae, Ord. Theales) has been hampered by the difficulties inherent in studying tropical dioecious, succulent, arborescent, epi- or hemiepiphytic taxa. Species identification by morphological traits often requires the terminal inflorescences and/or the succulent capsular fruits. To allow species differentiation based exclusively on vegetative tissue, a frequent necessity during ecological field studies, a procedure has been developed for rapid isolation of genomic DNA from Clusia leaf tissue followed by DNA amplification fingerprinting with a set of single arbitrary oligomer primers (23–27 mers). Fingerprints obtained with independent DNA preparations from one individual as well as DNA preparations from several individuals of the same species were identical for the major amplification products, although minor bands were somewhat variable. Polymorphic fingerprints have been obtained with 3 different primers for 3 Clusia species (C. minor L., C. alata Pl. & Tr., C. multiflora H. B. K.), and the related Oedematopus obovatus Spruce ex. PL (Clusiaceae). The interspecific Randomly Amplified Polymorphic Markers (RAPDs) thus obtained allow a rapid identification of vegetative tissue samples collected in the field, and will assist in a revision of the controversial taxonomy of the genus Clusia. 相似文献
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T. E. E. Grams A. Haag-Kerwer Elizabeth Olivares Erika Ball Stefan Arndt Marianne Popp Ernesto Medina Ulrich Lüttge 《Trees - Structure and Function》1997,11(4):240-247
Changes in chlorophyll a fluorescence during the day and diurnal-changes of net CO2-exchange and organic acid contents were determined in two species of the genus Clusia during the dry season in Venezuela. The investigations included plants of the C3/CAM intermediate species Clusia minor and the C3 species C. multiflora growing at exposed and shaded sites. Both species showed a C3 pattern of net CO2-exchange at the exposed site. In the shade under extreme drought stress C. minor showed a weak expression of CAM without CO2-uptake during the afternoon (phase IV of CAM). C. multiflora growing in the shade exhibited a C3-pattern of net CO2-exchange and a small but significant nocturnal accumulation of citrate. Shaded plants of C. minor were able to double their light utilisation for electron transport and to reduce non-photochemical quenching during phase
III compared to phase II of CAM. Furthermore, increase of electron transport rate through photosystem II in phase III of CAM
is correlated to decarboxylation of malate. At the exposed site C. multiflora was less negatively affected by high PPFD than C. minor. This was shown by a lower reduction of potential electron quantum yield (Fv/Fm) and higher light utilisation of electron transport of C. multiflora compared to C. minor. At the exposed site C. minor did not make use of the CAM option to increase light utilisation of electron transport and to reduce non-photochemical quenching
as did the plants growing in the shade.
Received: 20 March 1996 / Accepted: 24 June 1996 相似文献
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Britta Herzog T. E. E. Grams Angela Haag-Kerwer Erika Ball A. C. Franco U. Lüttge 《Plant biology (Stuttgart, Germany)》1999,1(3):357-364
Abstract: The large majority of the Ca . 150 species of the neotropical shrub and tree genus Clusia have the potential to perform Crassulacean acid metabolism (CAM). They are either obligate CAM plants or C3 /CAM intermediate plants. Only a very small percentage of the plants studied so far are apparently obligate C3 species. Among these was C. criuva , until recent laboratory studies showed that it may also have a certain CAM capacity under artificial stress conditions. Measurements of stomatal conductance (porometry) and chlorophyll fluorescence variables of C. criuva occurring along a transect from deep shade inside a gallery forest across the semi-shaded ecotone towards a cerrado and into the exposed cerrado itself in central Brazil now show that it can adapt its photosynthetic apparatus to effective performance of C3 photosynthesis under highly different photosynthetic photon flux densities. In addition, however, it does have a certain potential for CAM and cannot be considered as a strictly obligate C3 plant. Should a basic capacity for performing CAM be a general property of the genus, the quest for CAM traits in other remaining putatively obligate C3 species of the genus ought to be pursued. 相似文献
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Eduardo A. de Mattos T. E. E. Grams Erika Ball Augusto C. Franco A. Haag-Kerwer Britta Herzog Fabio R. Scarano U. Lüttge 《Trees - Structure and Function》1997,11(6):363-369
Diurnal measurements of chlorophyll fluorescence parameters and stomatal conductance to water vapour were carried out in
five woody species and a bromeliad from two coastal vegetation types in Brazil, the rock outcrop of Pao de Acúcar and the
sand dunes of Macaé. The environmental conditions of both study sites are characterized by high temperatures and light levels.
The studied species comprised C3 plants with different degrees of stomatal closure during the day, overall daily stomatal conductance and a plant with a typical
CAM pattern. Plants on Pao de Acúcar exhibited only a small decline in potential quantum yield throughout the day. The non-photochemical
quenching and the approximate photosynthetic electron transport rates were maximal during the peak of irradiance. In Macaé,
light response curves of fluorescence parameters in the CAM-tree Clusia hilariana showed a clear differentiation between phases III and IV of CAM. In phase III, decarboxylation of organic acids probably maintained
high internal CO2 levels and there was only a small decrease in photochemical quenching with saturating light levels. In phase IV, the depletion
of the organic acid pool and low stomatal conductances resulted in much lower levels of effective quantum yield and a substantial
increase in both 1-qP and non-photochemical quenching with increasing light levels. This behaviour during phase IV in the CAM-tree C. hilariana was comparable to the performance of the C3-Clusia
C. aff parviflora at Pao de Acúcar. It is seen that both the C3 species and the CAM tree occurring in the two coastal communities effectively adjust their photochemical efficiency to environmental
conditions and especially to diurnal variations of stress.
Received: 29 April 1996 / Accepted: 14 November 1996 相似文献
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Heiss Senta Schäfer Holger J. Haag-Kerwer Angela Rausch Thomas 《Plant molecular biology》1999,39(4):847-857
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