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32. Comparative photosynthesis characteristics of Calycanthus chinensis and Chimonanthus praecox
- Creator:
- Mao, L. Z., Lu, H. F., Wang, Q., and Cai, M. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biodiversity, chlorophyll content and fluorescence, endangered plant, irradiance, net photosynthetic rate, species differences, temperature, and transpiration
- Language:
- Multiple languages
- Description:
- Calycanthus chinensis is an endangered plant of the national second-grade protection of China restricted in a small area in Zhejiang Province. We studied parameters of photosynthesis, chlorophyll (Chl) contents, and Chl fluorescence (minimum fluorescence, F0, maximum fluorescence, Fm, variable fluorescence, Fv, and Fv/Fm) of C. chinensis and Chimonanthus praecox. C. chinensis had lower compensation irradiance but higher saturation irradiance than C. praecox. Hence C. chinensis has more advantage in obtaining and utilizing photon energy and higher Chl content, and is more adaptive to higher temperature and propitious to thermal dissipation than C. praecox. In addition, C. chinensis produces abundant, well-preserved seed with a higher germination rate and a wider adaptability to temperature than C. praecox. Thus C. chinensis is prone to survival and viability, and gets rid of the endangered plant species of the national second-grade protection of China. and L. Z. Mao ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33. Comparison of gas exchange and chlorophyll fluorescence of low-potassium-tolerant and -sensitive soybean [Glycine max (L.) Merr.] cultivars under low-potassium condition
- Creator:
- Li, X.-T., Cao, P., Wang, X.-G., Cao, M.-J., and Yu, H.-Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chlorophyll fluorescence, low-K stress, mesophyll resistance, net photosynthetic rate, and stomatal conductance
- Language:
- Multiple languages
- Description:
- The effects of potassium (K) deficiency on chlorophyll (Chl) content, photosynthetic gas exchange, and photosystem II (PSII) photochemistry during the seedling stage were investigated in two soybean [Glycine max (L.) Merr.] cultivars, low-K sensitive Tiefeng31 and low-K tolerant Shennong6. The cultivars were grown hydroponically in K-sufficient (KS) and K-deficient (KD) solutions. Photosynthetic gas exchange and Chl content in Tiefeng31 were severely affected by the low K condition, but were almost unaffected in Shennong6. This difference is in accordance with the PSII photochemistry in the plants, indicating that the photosynthetic apparatus of Shennong6 is more tolerant to low-K stress than that of Tiefeng31. and X.-T. Li ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34. Comparison of photosynthetic activity of Orychophragmus violaceus and oil-seed rape
- Creator:
- Wu, Y. Y., Wu, X. M., Li, P. P., Zhao, Y. G., Li, X. T., and Zhao, X. Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Brassica, carbonic anhydrase, net photosynthetic rate, and photosynthetic midday depession
- Language:
- Multiple languages
- Description:
- Orychophragmus violaceus, Brassica campestris cv. Chuanyou No.8, and Brassica juncea cv. Luzhousileng diurnal changes of net photosynthetic rate (PN) and activities of carbonic anhydrase (CA) of leaves were studied. One uni-modal curve occurred at the diurnal changes of PN in O. violaceus, but bimodal curves were found in B. campestris and B. juncea. Thus photosynthetic midday depression was not found in O. violaceus but in both Brassica species. Midday depression of PN in O. violaceus was not related to high temperature or low humidity at midday but to the activity of CA. and Y. Y. Wu ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
35. Comparison of some photosynthetic characters between two hybrid rice combinations differing in yield potential
- Creator:
- Jiang, Hua, Wang, Xue-Hua, Deng, Qi-Yun, Yuan, Long-Ping, and Xu, Da-Quan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation efficiency, chlorophyll, compensation CO2 concentration, compensation irradiance, dark respiration, net photosynthetic rate, Oryza sativa, photosystem 2, quantum yield, and stomatal conductance
- Language:
- Multiple languages
- Description:
- Photosynthetic characteristics of two hybrid rice combinations, Peiai 64S/E32 and Shanyou 63, were compared at the panicle differentiation stage. As compared with Shanyou 63, the new combination Peiai 64S/E32 showed a significantly higher net photosynthetic rate (PN), apparent quantum yield of carbon assimilation (Φc), carboxylation efficiency (CE), and photorespiratory rate (RP) as well as leaf chlorophyll content, but a significantly lower dark respiration rate (RD) and compensation irradiance (Ic). It also showed a slightly higher photochemical efficiency (Fv/Fm and ΔF/Fm') of photosystem 2, a lower non-photochemical quenching (qN), and a similar CO2 compensation concentration (Γ) as compared to Shanyou 63. and Hua Jiang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
36. Compensatory acclimated mechanisms of photoprotection in a Xa mutant of Lycopersicon esculentum Mill.
- Creator:
- Wang, Y. J., Xia, X. J. , Zhou, Y. H., and Yu, J. Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, CO2, concentration, net photosynthetic rate, non-photochemical quenching, photoprotection, photosynthetic electron flux, quenching, reactive oxygen species, stomatal conductance, tomato, and xanthophyll cycle
- Language:
- Multiple languages
- Description:
- To probe the role of xanthophylls in non-photochemical quenching (NPQ) and the compensatory acclimated photoprotection mechanisms, a tomato (Lycopersicon esculentum Mill. cv. Ailsa Craig) Xa mutant with deficit in lutein (L) and neoxanthin (N) contents was used. The Xa mutant showed lowered NPQ, an increased degree of de-epoxidation state [(A+Z)/(V+A+Z)], and decreases of photosystem 2 (PS2) antenna size. Although the Xa mutant had a CO2 assimilation rate similar to that of Ailsa Craig, it exhibited a much larger stomatal conductance (gs) than Ailsa Craig. Decreased electron flux in PS2 (J PS2) for the Xa mutant was associated with electron flux for photorespiratory carbon oxidation (Jo) and alternative electron flux in PS2 (Ja) while electron flux for photosynthetic carbon reduction (Jc) was not different from Ailsa Craig. Moreover, the Xa mutant also exhibited higher activities of antioxidant enzymes, higher contents of ascorbate and glutathione, and lower contents of reactive oxygen species. Hence some compensatory acclimated mechanisms of photoprotection operated properly in the lack of NPQ and xanthophylls. and Y. J. Wang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
37. Contrasting responses of photosynthesis at low temperatures in different annual legume species
- Creator:
- Antolín, M. C., Hekneby, M., and Sánchez-Díaz, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, old acclimation, dry matter accumulation, leaf area ratio, net photosynthetic rate, photosystem 2, specific leaf area, ribulose-1,5-bisphosphate carboxylase, oxygenase, and stromal fructose-1,6-bisphosphatase
- Language:
- Multiple languages
- Description:
- Growth, net photosynthetic rate (PN), chlorophyll fluorescence induction kinetics, and stromal fructose-1,6-bisphosphatase (sFBPase) in annual legumes native to the Mediterranean region, two clovers (Trifolium subterraneum L. ssp. oxaloides Nyman cv. Clare and T. michelianum Savi cv. Giorgia) and two Medicago species (M. polymorpha L. cv. Anglona and M. truncatula Gaertn. cv. Paraggio), shifted from 20 to 10 °C for 1 d or developed at 10 °C were compared with controls kept at 20 °C. Cold development produced a larger stimulation of growth in the clover cv. Giorgia and the Medicago cv. Paraggio. Transferring plants to low temperatures affected PN relatively less in clovers than in Medicago plants. Development at 10 °C relieved the inhibition of photosynthesis in Giorgia and Paraggio, but not in Clare and Anglona, which correlated with increases in the maximum rate of carboxylation by ribulose-1,5-bisphosphate carboxylase/oxygenase, RuBPCO (Vcmax), and the photon-saturated rate of electron transport (Jmax). In Medicago, transfer from high to low temperature inhibited photosynthesis in a lesser extent in Anglona than in Paraggio, which showed severe limitations at level of Vcmax and Jmax. Development at 10 °C in Paraggio produced an efficient photosynthetic cold acclimation, this being associated with a two-fold increase of quantum yield of photosystem 2 electron transport (ΔF/F'm) and with the activity of sFBPase. By contrast, Anglona showed an irreversible inhibition of PN coupled with the reduction of carbon metabolism by impairment of Calvin cycle enzyme activities such as RuBPCO and sFBPase, resulting in a poor cold acclimation of photosynthesis in this cultivar. and M. C. Antolín, M. Hekneby, M. Sánchez-Díaz.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
38. Contribution of pre-anthesis assimilates and current photosynthesis to grain yield, and their relationships to drought resistance in wheat cultivars grown under different soil moisture
- Creator:
- Inoue, T., Inanaga, S., Sugimoto, Y., and El Siddig, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- cultivar differences, intercellular CO2 concentration, net photosynthetic rate, remobilization, stomatal conductance, Triticum aestivum, and water stress
- Language:
- Multiple languages
- Description:
- We investigated the relative importance of pre-anthesis assimilates stored in plant parts, mainly in the stem, and post-anthesis photosynthesis to drought resistance in wheat (Triticum aestivum L.) cultivars Hongwangmai (drought resistant) and Haruhikari (drought sensitive) subjected to two soil moisture regimes: irrigated and non-irrigated. In the irrigated treatment, soil moisture was maintained near field capacity throughout the growing season, while in the non-irrigated treatment water was withheld from 81 d after sowing until maturity. Drought stress reduced grain yield of Hongwangmai and Haruhikari by 41 and 60 %, respectively. Remobilization of pre-anthesis assimilates to the grain (remobilization) was reduced by drought in Hongwangmai but increased in Haruhikari. The contribution of pre-anthesis assimilates to the grain decreased under non-irrigated treatment in Hongwangmai. However, under water stress, Hongwangmai maintained a higher net photosynthetic rate in the flag leaf than Haruhikari. These results indicated that maintenance of post-anthesis photosynthetic rate was related to drought resistance in Hongwangmai rather than to remobilization under drought stress. and T. Inoue ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
39. 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
40. 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