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532. Crassulacean Acid Metabolism 1975-2000, a check list

Creator:
Sayed, O. H.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
angiosperms, CAM inducers, CAM modifications, CAM types, carbon discrimination, ferns, gymnosperms, habitat, and phosphoenolpyruvate carboxylase
Language:
Multiple languages
Description:
A list of plant species documented over the past 25 years to exhibit Crassulacean Acid Metabolism (CAM) is presented. The list compiles all available information on these species including their growth habits, succulent parts, carbon isotope discrimination values, CAM types, CAM inducers, and CAM modifications.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

533. Crassulacean acid metabolism and survival of asexual propagules of Sedum wrightii

Creator:
Gravatt, D. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
asexual reproduction, dry mass, malic acid, plantlet, stonecrop, and water content
Language:
Multiple languages
Description:
In Sedum wrightii grown in a growth chamber, detached leaves could survive for at least 120 d with a high rate of success for propagule formation. The pattern of gas exchange, associated with CAM, may be important in extending the period during which the detached leaf remains physiologically active. The added benefit for the developing propagule, still attached to the "parent" leaf, is an additional source of water and saccharide reserves over an extended period necessary for rooting. Drought survival of propagules may be determined by the amount of water-storing tissue in the detached leaf.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

534. Crassulacean acid metabolism in the epiphytic fern Patycerium bifurcatum

Creator:
Rut, G., Krupa, J., Miszalski, Z., Rzepka, A., and Ślesak, I.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
abscisic acid, chlorophyll fluorescence, drought stress, malate, net photosynthetic rate, photosystem 2, and stomatal conductance
Language:
Multiple languages
Description:
The epiphytic fern Platycerium bifurcatum grows in different habitats characterized by drought and high irradiance stress. The plant shows diurnal malate oscillations, indicative for CAM expression only in cover leaves, but not in sporotrophophyll. In P. bifurcatum cover leaves exposed to high irradiance and desiccation, the decrease in both CO2 assimilation (PN) and stomatal conductance (gs) was accompanied with occurrence of diurnal malate oscillations. Exogenously applied abscisic acid (ABA) induced the decrease in PN and gs, but no clear change in malate oscillations. The measurements of the maximum quantum efficiency of photosystem 2 (Fv/Fm) under high irradiance showed distinct photoinhibition, but no clear changes in Fv/Fm due to desiccation and ABA-treatment were found. and G. Rut ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

535. Critical responses of photosynthetic efficiency of goldspur apple tree to soil water variation in semiarid loess hilly area

Creator:
Zhang, S. Y., Zhang, G. C. , Gu, S. Y., Xia, J. B., and Zhao, J. K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, critical efficiency, goldspur apple tree, loess hilly area, photosynthetic efficiency, and soil water content
Language:
Multiple languages
Description:
Goldspur apple (Malus pumila cv. Goldspur) is one of the main fruit trees planted in semiarid loess hilly areas. The photosynthetic efficiency in leaves of eight-year-old trees were studied under different soil water conditions with a Li-6400 portable photosynthesis system and a Li-Cor1600 portable steady state porometer in order to explore the effects of soil water stress on photosynthesis and the suitable soil water content (SWC) for water-saving irrigation of apple orchards. The results showed that the leaf net photosynthetic rate (P N), transpiration rate (E), water-use efficiency (WUE), stomatal conductance (gs), intercellular CO2 concentration (Ci), and stomatal limiting value (Ls) displayed different threshold responses to soil water variation. When SWC was within a range of about 60%-86% of field capacity (FC), PN and E were maintained in a relative steady state. At an elevated level but below 60% of FC, both PN and E decreased evidently with decreasing soil moisture. The SWC needed to support WUE in a relatively steady state and at a high level was in the range of about 50%-71% of FC. When SWC was less than 48% of FC, g s and Ls declined with decreasing soil moisture, while Ci increased rapidly. Based on the analysis of the stomatal limitation of photosynthesis using two criteria (Ci and Ls) suggested by Farquhar and Sharkey, it was implied that the predominant cause of restricting PN had changed from stomatal limitation to nonstomatal one under severe water stress. In terms of water-saving irrigation for enhancing water-use efficiency, it was concluded that in semiarid loess hilly areas, the suitable range of SWC for water-saving irrigation in goldspur apple orchards is in the range of about 50%-71% of FC, and the most severe degree of soil water stress tolerated for photosynthesis is about 48% of FC. and S. Y. Zhang ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

537. Cultivar differences in photosynthetic tolerance to photooxidation and shading in rice (Oryza sativa L.)

Creator:
Jiao, Demao and Li, Xia
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll, grain, irradiance, net photosynthetic rate, photooxidation, photosynthetic characteristics, photosystems 1 and 2, ribulose-1,5-bisphosphate carboxylase, shoot dry mass, and superoxide dismutase
Language:
Multiple languages
Description:
Forty-four genotypes from the rice germplasm were identified under photoinhibition/photooxidation and shade conditions and divided into four basic types: (1) cultivars tolerant to both photooxidation and shading, (2) cultivars tolerant to photooxidation but sensitive to shading, (3) cultivars tolerant to shading but sensitive to photooxidation, and (4) cultivars sensitive to both photooxidation and shading. Photosynthetic characteristics of a cultivar tolerant (cv. Wuyugeng 3) and a cultivar sensitive (cv. Xiangxian) to photooxidation and shading were compared. The photochemical efficiency (Fv/Fm) of photosystem 2 (PS2) and the content of PS2-D1 protein in the tolerant cultivar Wuyugeng 3 decreased less under photooxidative conditions as compared with Xiangxian. Under similar conditions, superoxide dismutase was induced rapidly to a higher activity and the active oxygen (O-) built up to a lower level in Wuyugeng 3 than in Xiangxian. Net photosynthetic rate (PN) decreased by 23 % in Wuyugeng 3 vs. 64 % in Xiangxian. Shading (80 %) during the booting stage caused only small decreases (7-13 %) in ribulose-1,5-bisphosphate carboxylase activity and PN in Wuyugeng 3 but severe decreases (57-64 %) were observed in Xiangxian which corresponded to the decreases in grain yield of the two cultivars (38 and 73 %, respectively). We described a simple and effective screening method and physiological basis for breeding crops for enhanced tolerance to both high and low irradiance. and Demao Jiao, Xia Li.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

538. Cultivar variation in cotton photosynthetic performance under different temperature regimes

Creator:
Pettigrew, W. T.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
chlorofyl, bavlna, teplota, chlorophyll, cotton, temperature, fluorescence chlorofylu, kultivary, abiotický stres, mezibuněčná koncentrace CO2, list, výměna plynu, termotolerance, efektivita využívání vody, chlorophyll fluorescence, cultivars, abiotic stress, intercellular CO2 concentration, leaf, gas exchange, maximum quantum yield, thermotolerance, water-use efficiency, 2, and 581
Language:
Multiple languages
Description:
Cotton (Gossypium hirsutum L.) yields are impacted by overall photosynthetic production. Factors that influence crop photosynthesis are the plants genetic makeup and the environmental conditions. This study investigated cultivar variation in photosynthesis in the field conditions under both ambient and higher temperature. Six diverse cotton cultivars were grown in the field at Stoneville, MS under both an ambient and a high temperature regime during the 2006-2008 growing seasons. Mid-season leaf net photosynthetic rates (PN) and dark-adapted chlorophyll fluorescence variable to maximal ratios (Fv/Fm) were determined on two leaves per plot. Temperature regimes did not have a significant effect on either PN or Fv/Fm. In 2006, however, there was a significant cultivar × temperature interaction for PN caused by PeeDee 3 having a lower PN under the high temperature regime. Other cultivars' PN were not affected by temperature. FM 800BR cultivar consistently had a higher PN across the years of the study. Despite demonstrating a higher leaf Fv/Fm, ST 5599BR exhibited a lower PN than the other cultivars. Although genetic variability was detected in photosynthesis and heat tolerance, the differences found were probably too small and inconsistent to be useful for a breeding program., W. T. Pettigrew., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

539. Cyanide-resistant respiratory pathway is involved in the high-light systemic acquired acclimation of kidney bean

Creator:
Feng, H.-Q., Tang, S.-Z., Sun, K., Jia, L.-Y., and Wang, R.-F.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, fazol obecný, photosynthesis, Phaseolus vulgaris, bean leaf, chlorophyll fluorescence, salicylhydroxamic acid, 2, and 581
Language:
Multiple languages
Description:
After exposing one half of a low light-adapted kidney bean (Phaseolus vulgaris) leaf to high light, parameters of chlorophyll (Chl) a fluorescence, such as PSII operating efficiency, PSII maximum efficiency under light, and photochemical quenching, decreased in the opposite half of the same leaf, whereas the capacity of the cyanide-resistant respiratory pathway significantly increased. When one half of the low light-adapted leaf was exposed to low light, the opposite half pretreated with 1 mM salicylhydroxamic acid (SHAM, an inhibitor of the cyanide-resistant respiratory pathway) did not exhibit significant changes in the Chl fluorescence values compared with the without SHAM pretreatment. However, after exposing one half of the low light-adapted leaf to high light, the opposite half pretreated with 1 mM SHAM showed lower Chl fluorescence values than that without SHAM pretreatment. Our results indicate that partial exposure of the low light-adapted leaf to high light can impose a systemic stress on the PSII photochemistry. The enhanced capacity of the cyanide-resistant respiratory pathway may be involved in the maintenance of the photosynthetic performance in the leaf tissues experiencing high light-induced systemic stress., H.-Q. Feng, S.-Z. Tang, K. Sun, L.-Y. Jia, R.-F. Wang., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

540. Daily irradiance and feedback inhibition of photosynthesis at elevated carbon dioxide concentration in Brassica oleracea

Creator:
Bunce, J. A. and Sicher, R. C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
collard, irradiance, kohlrabi, saccharides, stomatal conductance, and variety differences
Language:
Multiple languages
Description:
The fundamental cause of down-regulation of photosynthesis at elevated carbon dioxide concentration (EC) is thought to be a slower rate of utilization of saccharides than their stimulated rate of production, but there are few studies directly supporting this idea under field conditions. We hypothesized that within Brassica oleracea, down-regulation would not occur in kohlrabi because it has a large sink for saccharides in an enlarged stem, but would occur in collards, which lack this sink. Field tests were consistent with this hypothesis. In collards, the degree of down-regulation of photosynthesis in plants grown at EC varied depending on the daily integral of photosynthetically active radiation (PAR) of the day prior to the measurement of photosynthetic capacity, as did leaf saccharide content. However, EC did not result in lower leaf contents of chlorophyll, soluble protein, ribulose-1,5-bisphosphate carboxylase, or nitrate in collards, nor was there any evidence of a triose phosphate utilization rate limiting photosynthesis. Experiments in controlled environment chambers confirmed that there was a threshold response for the down-regulation of photosynthesis in collards at EC to the PAR of the previous day, with down-regulation only occurring above a minimum daily integral of PAR. Down-regulation of photosynthesis could be induced in plants grown at ambient carbon dioxide by a single night at low temperature or by a single day with high PAR and EC. In the controlled environment study, the degree of down-regulation of photosynthesis was highly correlated with leaf glucose, fructose, and sucrose contents, and less well correlated with starch content. Hence down-regulation of photosynthesis at EC in collards in the field represented feedback inhibition from the accumulation of soluble saccharides and day-to-day variation in its occurrence was predictable from the weather. and J. A. Bunce, R. C. Sicher.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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