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The effect of CaCl₂ on calcium content, photosynthesis, and chlorophyll fluorescence of tung tree seedlings under drought conditionsOriginal Papers

Z. Li, X. F. Tan, K. Lu, Z. M. Liu, L. L. Wu

Photosynthetica 2017, 55(3):553-560 | DOI: 10.1007/s11099-016-0676-x

The study investigated the effects of different CaCl₂ concentrations (2, 5, and 10 mM) on photosynthetic enzymatic activities, photosynthesis, and chlorophyll fluorescence of tung tree seedlings under drought conditions. Plants were sprayed with either CaCl₂ or distilled water until run-off. Irrigation was then withheld to induce drought stress. The strength of drought stress was evaluated by relative leaf water content and soil water content, which was 27.3 and 9.5% on day 0 and day 12, respectively. Drought stress decreased activities of ribulose-1,5-bisphosphate carboxylase/oxygenase and phosphoenolpyruvate carboxylase,...

Predictive capability of a leaf optical meter for determining leaf pigment status during senescenceOriginal Papers

G.Y. Li, D.P. Aubrey, H.Z. Sun

Photosynthetica 2017, 55(3):543-552 | DOI: 10.1007/s11099-016-0678-8

We conducted an experiment to assess the predictive capability of a leaf optical meter for determining leaf pigment status of Acer mono Maxim., A. ginnala Maxim., Quercus mongolica Fisch., and Cornus alba displaying a range of visually different leaf colors during senescence. Concentrations of chlorophyll (Chl) a, Chl b, and total Chl [i.e., Chl (a+b)] decreased while the concentration of carotenoids (Car) remained relatively static for all species as leaf development continued from maturity to senescence. C. alba exhibited the lowest average concentration of Chl (a+b), Chl a,...

Soil water content and photosynthetic capacity of spring wheat as affected by soil application of nitrogen-enriched biochar in a semiarid environmentOriginal Papers

S. Yeboah, R. Zhang, L. Cai, L. Li, J. Xie, Z. Luo, J. Wu, D. L. Antille

Photosynthetica 2017, 55(3):532-542 | DOI: 10.1007/s11099-016-0672-1

A field trial was conducted to determine the effect of nitrogen-enriched biochar on soil water content, plant's photosynthetic parameters, and grain yield of spring wheat at the Dingxi Experimental Station during the 2014 and 2015 cropping seasons. Results showed that biochar applied with nitrogen fertilizer at a rate of 50 kg ha^-1 of N (BN₅₀) increased soil water content in the 0-30 cm depth range by approximately 40, 32, and 53% on average at anthesis, milking, and maturity, respectively, compared with zero-amendment (CN₀). Stomatal conductance and net photosynthetic rate after the BN₅₀ treatment increased...

Lotus corniculatus L. response to carbon dioxide concentration and radiation level variationsOriginal Papers

P. Kostopoulou, M. Karatassiou

Photosynthetica 2017, 55(3):522-531 | DOI: 10.1007/s11099-016-0671-2

Carbon dioxide concentration and light conditions may greatly vary between mountainous and lowland areas determining the photosynthetic performance of plants species. This paper aimed to evaluate the photosynthetic responses of Lotus corniculatus, growing in a mountain and a lowland grassland, under low and high radiation and CO₂ concentration. Net photosynthetic rate, stomatal conductance, transpiration rate, and intercellular CO₂ concentration were measured while the water-use efficiency and the ratio of variable to maximal fluorescence were calculated. Photosynthetic response curves to different levels of radiation and...

Effectiveness of cyanobacteria and green algae in enhancing the photosynthetic performance and growth of willow (Salix viminalis L.) plants under limited synthetic fertilizers applicationOriginal Papers

M. Grzesik, Z. Romanowska-Duda, H. M. Kalaji

Photosynthetica 2017, 55(3):510-521 | DOI: 10.1007/s11099-017-0716-1

The physiological response of plants to triple foliar biofertilization with cyanobacteria and green algae under the conditions of limited use of chemical fertilizers was investigated. Triple foliar biofertilization with intact cells of Microcystis aeruginosa MKR 0105, Anabaena sp. PCC 7120, and Chlorella sp. significantly enhanced physiological performance and growth of plants fertilized with a synthetic fertilizer YaraMila Complex (1.0, 0.5, and 0.0 g per plant). This biofertilization increased the stability of cytomembranes, chlorophyll content, intensity of net photosynthesis, transpiration, stomatal conductance, and...

Atomic ratio of N to P influences the impact of UV irradiance on photosynthesis and growth in a marine dinoflagellate, Alexandrium tamarenseOriginal Papers

W.C. Guan, L. Li

Photosynthetica 2017, 55(3):501-509 | DOI: 10.1007/s11099-016-0670-3

The effects of the atomic ratio of N to P (N:P) on the response of Alexandrium tamarense to UV radiation (UVR) were investigated in this study. Artificial sea water of 5 different N:P ratios for indoor culture and with 3 different N:P ratios for outdoor culture were used for a period of 14 and 9 d, respectively. The short-term response of cells to UVR was analyzed using a fluorometer. Cells that acclimated to nutrient conditions at the Redfield value (16:1) showed the fastest growth rate and highest pigment concentrations in both indoor and outdoor conditions, compared to those acclimated to the non-Redfield conditions. Moreover, these physiological...

Photosynthetic and physiological responses of foxtail millet (Setaria italica L.) to low-light stress during grain-filling stageOriginal Papers

X. Y. Yuan, L. G. Zhang, L. Huang, X. Qi, Y. Y. Wen, S. Q. Dong, X. E. Song, H. F. Wang, P. Y. Guo

Photosynthetica 2017, 55(3):491-500 | DOI: 10.1007/s11099-016-0645-4

Two foxtail millet (Setaria italica L.) varieties were subjected to different shading intensity treatments during a grain-filling stage in a field experiment in order to clarify physiological mechanisms of low-light effects on the yield. Our results showed that the grain fresh mass per panicle, yield, photosynthetic pigment contents, net photosynthetic rate, stomatal conductance, effective quantum yield of PSII photochemistry, and electron transport rate decreased with the increase of shading intensity, whereas the intercellular CO₂ concentration increased in both varieties. In addition, shading changed a double-peak diurnal variation...

Ozone sensitivity of four Pakchoi cultivars with different leaf colors: physiological and biochemical mechanismsOriginal Papers

L. Zhang, S. Xiao, Y. J. Chen, H. Xu, Y. G. Li, Y. W. Zhang, F. S. Luan

Photosynthetica 2017, 55(3):478-490 | DOI: 10.1007/s11099-016-0661-4

Ozone (O₃) is important air pollutant inducing severe losses of horticultural production. Cultivars of the same species, but with different leaf colors, may differ in their ozone sensitivity. However, it has not been clarified yet if different leaf coloration influences such a sensitivity. In this study, two purple-leafed and two green-leafed cultivars of Pakchoi were selected for ozone fumigation (240 ± 20 nmol mol^-1, 09:00-16:00 h). Elevated O₃ decreased chlorophyll content, increased anthocyanin (Ant) content, damaged cell membrane integrity, enhanced antioxidative enzyme activities, depressed photosynthetic...

Effects of light quality on growth and development, photosynthetic characteristics and content of carbohydrates in tobacco (Nicotiana tabacum L.) plantsOriginal Papers

L. Y. Yang, L. T. Wang, J. H. Ma, E. D. Ma, J. Y. Li, M. Gong

Photosynthetica 2017, 55(3):467-477 | DOI: 10.1007/s11099-016-0668-x

In this study, effects of yellow (Y), purple (P), red (R), blue (B), green (G), and white (W) light on growth and development of tobacco plants were evaluated. We showed that monochromatic light reduced the growth, net photosynthetic rate (P _N), stomatal conductance, intercellular CO₂, and transpiration rate of tobacco. Such a reduction in P _N occurred probably due to the stomatal limitation contrary to plants grown under W. Photochemical quenching coefficient (qP), maximal fluorescence of dark-adapted state, effective quantum yield of PSII photochemistry (Φ_PSII), and maximal quantum yield...

Photosynthetic response of tetraploid and hexaploid wheat to water stressOriginal Papers

Y. P. Li, Y. Y. Li, D. Y. Li, S. W. Wang, S. Q. Zhang

Photosynthetica 2017, 55(3):454-466 | DOI: 10.1007/s11099-016-0659-y

Photosynthetic characteristics of ear and flag leaves of wheat species, tetraploid Triticum dicoccoides Kom and hexaploid Bima1, were studied in plants grown under well-watered (WW) and water-stressed (WS) conditions. Compared to ears, flag leaves exhibited higher photosynthetic rate (P _N) at the filling stage, but more severe decrease under WS. P _N in the tetraploid wheat ear remained higher than that in the hexaploid wheat during the grain-filling stage. Water stress decreased PN in both the organs; this decline was caused by a reduction in Rubisco activity, not by drought-induced stomatal limitation. Tetraploid...

Effects of paclobutrazol on cultivars of Chinese bayberry (Myrica rubra) under salinity stressOriginal Papers

Y. Hu, W. Yu, T. Liu, M. Shafi, L. Song, X. Du, X. Huang, Y. Yue, J. Wu

Photosynthetica 2017, 55(3):443-453 | DOI: 10.1007/s11099-016-0658-z

Salt stress is one of the most critical factors hindering the growth and development of plants. Paclobutrazol (PBZ) is widely used to minimize this problem in agriculture because it can induce salt stress tolerance in plants. This study investigated the effects of PBZ on salt tolerance of seedlings from two Chinese bayberry cultivars (i.e., Wangdao and Shenhong). Plants were treated with three salt concentrations (0, 0.2, and 0.4 % NaCl) and two PBZ concentrations (0 and 2.0 μmol L^-1). Application of PBZ increased a relative water content, proline content, chlorophyll (a+b) content, and antioxidant enzyme activities in both...

Morphological recognition with the addition of multi-band fluorescence excitation of chlorophylls of phytoplanktonOriginal Papers

M. Lauffer, F. Genty, S. Margueron, J. L. Collette

Photosynthetica 2017, 55(3):434-442 | DOI: 10.1007/s11099-016-0663-2

The recognition of aquatic organisms plays a crucial role in the monitoring of the pollution and for the adoption of rapid preventive actions. A compact microscopic optical imaging system is proposed in order to acquire and treat the multibands fluorescence of several pigments in phytoplankton organisms. Two algorithms for automatic recognition of phytoplankton were proposed with a minimum number of calibration parameters. The first algorithm provides a morphological recognition based on "watershed" segmentation and Fourier descriptors, while the second one builds fluorescence pigment images by "k-means" partition of intensity ratios. The operation...

Relationship between photosynthetic pigments and chlorophyll fluorescence in soybean under varying phosphorus nutrition at ambient and elevated CO₂Original Papers

S. K. Singh, V. R. Reddy, D. H. Fleisher, D. J. Timlin

Photosynthetica 2017, 55(3):421-433 | DOI: 10.1007/s11099-016-0657-0

To assess the relationship between chlorophyll (Chl) fluorescence (CF) and photosynthetic pigments, soybean was grown under varying phosphorus (P) nutrition at ambient and elevated CO₂ (EC). The EC stimulated, but P deficiency decreased plant height, node numbers, and leaf area concomitantly with the rates of stem elongation, node addition, and leaf area expansion. Under P deficiency, CF parameters and pigments declined except that carotenoids (Car) were relatively stable indicating its role in photoprotection. The CF parameters were strongly related with Chl concentration but not with Chl a/b or Car. However, total Chl/Car showed...

Light availability and soil flooding regulate photosynthesis of an imperiled shrub in lowland forests of the Mississippi Alluvial Valley, USAOriginal Papers

B. R. Lockhart, E. S. Gardiner, T. D. Leininger, M. S. Devall, A. D. Wilson, K. F. Connor, P. B. Hamel, N. M. Schiff

Photosynthetica 2017, 55(3):411-420 | DOI: 10.1007/s11099-016-0655-2

Physiological responses to light availability and soil flooding on Lindera melissifolia (Walt.) Blume were studied. Shrubs were grown under 70, 37 or 5% of full sunlight with either 0, 45, or 90 d of soil flooding. We measured leaf photosynthetic rate (PN) to test the hypothesis that soil flooding reduces P _N in L. melissifolia following shrub acclimation to low light availability. Results showed that light availability and soil flooding interacted to affect P _N. In the 0 d and 45 d flooding regimes (flood water removed 36-39 d prior to measurement), P _N was similar between shrubs...

Leaf anatomy and photosynthetic efficiency of Acrostichum danaeifolium after UV radiationOriginal Papers

A. M. Fonini, J. B. Barufi, É. C. Schmidt, A. C. Rodrigues, Á. M. Randi

Photosynthetica 2017, 55(3):401-410 | DOI: 10.1007/s11099-016-0654-3

This paper reports effects of ultraviolet B (UVB) radiation on leaf anatomy and contents of chlorophyll and carotenoids, as well as photosynthetic parameters, in young sporophytes of Acrostichum danaeifolium Langsd. & Fisch. (Polypodiopsida, Pteridaceae) exposed to UV radiation treatments for 1 h daily for six weeks. The leaves showed large aerenchyma and present chloroplasts in both epidermises. After cultivation under PAR + UVA + UVB, leaves showed curling and malformed stomata on the abaxial face. After the UV treatment, chloroplasts in leaves were arranged against the inner wall of the epidermal cells. Transmission electron microscopy...

Sustainability of photosynthesis research-when research is impeded by the cults of audit and managementOriginal Papers

M. Tsimilli-Michael, P. Haldimann

Photosynthetica 2017, 55(2):391-400 | DOI: 10.1007/s11099-017-0686-3

In this article, related to a talk given at the International Meeting "Photosynthesis Research for Sustainability-2015", we honor Dr. George C. Papageorgiou, a highly respected scientist and an outstanding teacher and mentor. Praising him for these virtues, indispensable for research sustainability, we also bring to discussion aspects that undermine nowadays both education and research sustainability. We argue that these aspects are principally created by the predominant bureaucratic system, which, by favoring short-term utilitarian orientations and obeying "market laws", jeopardizes university freedom and autonomy, and has turned to "measuring" scientific...

Benzoxazolin-2-(3H)-one reduces photosynthetic activity and chlorophyll fluorescence in soybeanBrief Communications

A. V. Parizotto, R. Marchiosi, G. A. Bubna, J. M. Bevilaqua, A. P. Ferro, M. L. L. Ferrarese, O. Ferrarese-Filho

Photosynthetica 2017, 55(2):386-390 | DOI: 10.1007/s11099-016-0656-1

Benzoxazolin-2-(3H)-one (BOA) has been tested in many plants species, but not in soybean (Glycine max). Thus, a hydroponic experiment was conducted to assess the effects of BOA on soybean photosynthesis. BOA reduced net photosynthetic rate, stomatal conductance, and effective quantum yield of PSII photochemistry without affecting intercellular CO₂ concentration or maximal quantum yield of PSII photochemistry. Results revealed that the reduced stomatal conductance restricted entry of CO₂ into substomatal spaces, thus limiting CO₂ assimilation. No change found in intercellular CO₂ concentration...

Arbuscular mycorrhizal fungi enhanced the growth, photosynthesis, and calorific value of black locust under salt stressOriginal Papers

X. Q. Zhu, M. Tang, H. Q. Zhang

Photosynthetica 2017, 55(2):378-385 | DOI: 10.1007/s11099-017-0662-y

Saline soils spread wildly in the world, therefore it is important to develop salt-tolerant crops. We carried out a pot study in order to determine effects of arbuscular mycorrhizal fungi (AMF) (Rhizophagus irregularis and Glomus versiforme) in black locust seedlings under salt (NaCl) stress. The results showed that AMF enhanced in seedlings their growth, photosynthetic ability, carbon content, and calorific value. Under salt stress, the biomass of the seedlings with R. irregularis or G. versiforme were greater by 151 and 100%, respectively, while a leaf area increased by 197 and 151%, respectively. The seedlings colonized...

Response of stem sap flow and leaf photosynthesis in Tamarix chinensis to soil moisture in the Yellow River Delta, ChinaOriginal Papers

J. B. Xia, Z. G. Zhao, J. K. Sun, J. T. Liu, Y. Y. Zhao

Photosynthetica 2017, 55(2):368-377 | DOI: 10.1007/s11099-016-0651-6

Soil moisture is the main limiting factor for vegetation growth at shell ridges in the Yellow River Delta of China. The objective of this study was to explore the soil moisture response of photosynthetic parameters and transpiration in Tamarix chinensis Lour., a dominant species of shell ridges. Leaf photosynthetic light-response parameters and sap flow were measured across a gradient of relative soil water content (RWC), from drought (23%) to waterlogging (92%) conditions. Leaf photosynthetic efficiency and stem sap flow of T. chinensis showed a clear threshold response to soil moisture changes. Leaf net photosynthetic rate, water-use...

Light quality modifies the expression of photosynthetic genes in maize seedlingsOriginal Papers

T. D. Liu, X. W. Zhang, Y. Xu, S. Q. Liu, X. W. Chen

Photosynthetica 2017, 55(2):360-367 | DOI: 10.1007/s11099-016-0227-5

Although maize (Zea mays L.) plants utilize light efficiently, the expression of high light-efficient genes and stomatal factors is regulated by light conditions and affects photosynthesis of plants. In this study, we investigated the effects of different light qualities on the expression of the photosynthetic genes, such as pep1, pdk1, ZmSTOMAGEN, and psad1, and on stomatal function in maize seedlings. For both maize genotypes, Zhengdan 958 and Xianyu 335, light with wavelengths shorter than 490 nm enhanced the expression of pdk1 and ZmSTOMAGEN, whereas the expression of pdk1 positively correlated...

Paclobutrazol-induced alleviation of water-deficit damage in relation to photosynthetic characteristics and expression of stress markers in contrasting wheat genotypesOriginal Papers

S. K. Dwivedi, Ajay Arora, S. Kumar

Photosynthetica 2017, 55(2):351-359 | DOI: 10.1007/s11099-016-0652-5

Our experiment was conducted in order to find out effects of paclobutrazol (PBZ; 30 μl l^-1) on morphology, photosynthetic process, and stress markers under water surplus and deficit conditions in several wheat genotypes. Study revealed that relative water content (RWC), photosynthetic rate, and maximal quantum yield of PSII (F_V/F_M) was improved after a PBZ application both under irrigation and water deficit across the genotypes, while the stomatal conductance was reduced. Further, the application of PBZ led to reduced leaf area in wheat genotypes. Moreover, a proline content was higher in the wheat genotypes under...

Selenium delays leaf senescence in oilseed rape plantsOriginal Papers

S. Rahmat, R. Hajiboland, N. Sadeghzade

Photosynthetica 2017, 55(2):338-350 | DOI: 10.1007/s11099-016-0643-6

Effect of selenium on leaf senescence was studied in oilseed rape plants treated with 10 μM Na₂SeO₄ at a rosette growth stage. In addition to developmental senescence, N deficiency and leaf detachment were used for induction of senescence. Nonphotochemical quenching declined in old leaves as senescence became more advancing but rose progressively in the plants supplied by Se. The total carbohydrate and protein pools decreased with leaf age, while increased by the Se treatment. However, during senescence induced by N deficiency, Se did not change remarkably the C and N metabolism, but delayed senescence mainly through protection...

Expression quantitative trait loci analysis of the Rubisco activase gene in maizeOriginal Papers

Q. Sun, Y. Zhang, B. Chen, B. Jia, Z. L. Zhang, M. Cui, X. Kan, H. B. Shi, D. X. Deng, Z. T. Yin

Photosynthetica 2017, 55(2):329-337 | DOI: 10.1007/s11099-016-0242-6

Expression quantitative trait loci (eQTL) analyses were applied in order to identify genetic factors that are relevant to the expression of a β-isoform Rubisco activase gene in maize, namely ZmRCAβ, in this study. During two years, a maize recombinant inbred line population was measured for ZmRCAβ expression levels at the grain filling stage. Based on a genetic map containing 916 molecular markers, we detected five eQTLs, namely qRCA2.1 on chromosome 2, and qRCA4.1, qRCA4.2, qRCA4.3, and qRCA4.4 on chromosome 4. These eQTLs explained the phenotypic variation ranging from 6.14% to...

Photosynthetic responses of a wheat (Asakaze)-barley (Manas) 7H addition line to salt stressOriginal Papers

D. Szopkó, É. Darkó, I. Molnár, K. Kruppa, B. Háló, A. Vojtkó, M. Molnár-Láng, S. Dulai

Photosynthetica 2017, 55(2):317-328 | DOI: 10.1007/s11099-016-0241-7

The photosynthetic responses to salt stress were examined in a wheat (Triticum aestivum L. cv. Asakaze)-barley (Hordeum vulgare L. cv. Manas) 7H addition line having elevated salt tolerance and compared to the parental wheat genotype. For this purpose, increasing NaCl concentrations up to 300 mM were applied and followed by a 7-day recovery period. Up to moderate salt stress (200 mM NaCl), forcible stomatal closure, parallel with a reduction in the net assimilation rate (P _N), was only observed in wheat, but not in the 7H addition line or barley. Since the photosynthetic electron transport processes of wheat were not...

Arbuscular mycorrhizal fungus Rhizophagus irregularis influences key physiological parameters of olive trees (Olea europaea L.) and mineral nutrient profileOriginal Papers

M. Tekaya, B. Mechri, N. Mbarki, H. Cheheb, M. Hammami, F. Attia

Photosynthetica 2017, 55(2):308-316 | DOI: 10.1007/s11099-016-0243-5

In this study, we hypothesized that colonization of olive trees (Olea europaea L.) with the arbuscular mycorrhizal fungus Rhizophagus irregularis could modify the profiles of rhizosphere microbial communities with subsequent effects on nutrient uptake that directly affects olive tree physiology and performance. In this context, a greenhouse experiment was carried out in order to study the effects of mycorrhizal colonization by R. irregularis on photosynthesis, pigment content, carbohydrate profile, and nutrient uptake in olive tree. After six months of growth, photosynthetic rate in mycorrhizal (M) plants was significantly higher...

Evolution characteristics related to photosynthesis, growth and yield in some old and new cotton cultivarsOriginal Papers

H. H. Luo, H. L. Zhang, Y. L. Zhang, W. F. Zhang

Photosynthetica 2017, 55(2):301-307 | DOI: 10.1007/s11099-016-0223-9

Changes in photosynthetic attributes related to genetic improvement of cotton yield were studied in seven Chinese cotton cultivars widely grown in Xinjiang during the past 30 years. Our results showed that a chlorophyll (Chl) content and net photosynthetic rate (P _N) of the 1980s cultivar was the highest among all after 60 days from planting (DAP). However, after 75 DAP, the Chl content, P _N, and actual photochemical efficiency of PSII of the old cultivars declined gradually, whereas those of the new cultivars remained relatively high. Compared to the old cultivars, leaves of the new cultivars endured a longer period...

Effect of imazapic residues on photosynthetic traits and chlorophyll fluorescence of maize seedlingsOriginal Papers

W. C. Su, L. L. Sun, R. H. Wu, Y. H. Ma, H. L. Wang, H. L. Xu, Z. L. Yan, C. T. Lu

Photosynthetica 2017, 55(2):294-300 | DOI: 10.1007/s11099-016-0641-3

The influence of various concentrations of imazapic residues (0-800 μg kg^-1) on the growth, chlorophyll content, and photosynthetic characteristics of maize seedlings was studied in a greenhouse pot experiment. Plant height, root length, shoot dry mass, root dry mass, and total dry mass of maize declined with the increase of imazapic residue concentrations. The root/shoot ratio initially decreased and then increased in presence of imazapic, which indicated that the effects of imazapic residues on plant height and root length might differ in maize seedlings. Lowered chlorophyll content and net photosynthetic rate were observed in leaves...

Influence of low phosphorus concentration on leaf photosynthetic characteristics and antioxidant response of rice genotypesOriginal Papers

N. Veronica, D. Subrahmanyam, T. Vishnu Kiran, P. Yugandhar, V. P. Bhadana, V. Padma, G. Jayasree, S. R. Voleti

Photosynthetica 2017, 55(2):285-293 | DOI: 10.1007/s11099-016-0640-4

Influence of different phosphorus concentrations was studied in four rice varieties (Akhanphou, MTU1010, RP BIO 226, and Swarna) differing in their tolerance to low phosphorus. There was an increase in shoot and root dry mass with the increase in phosphorus concentration. At the low phosphorus concentration at both tillering and reproductive stages, Swarna, followed by Akhanphou, recorded maximum biomass for both roots and shoots, while the minimum was observed in RP BIO 226. Reduction in photosynthetic rate, stomatal conductance, transpiration rate, and internal CO₂ concentration at low phosphorus concentrations were observed at both tillering...

Effects of 5-aminolevulinic acid treatment on photosynthesis of strawberryOriginal Papers

Y. P. Sun, J. Liu, R. X. Cao, Y. J. Huang, A. M. Hall, C. B. Guo, L. J. Wang

Photosynthetica 2017, 55(2):276-284 | DOI: 10.1007/s11099-016-0667-y

Effects of root treatment with 5-aminolevulinic acid (ALA) on leaf photosynthesis in strawberry (Fragaria ananassa Duch.) plants were investigated by rapid chlorophyll fluorescence and modulated 820 nm reflection using 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) and methyl viologen (MV). Our results showed that ALA treatments increased the net photosynthetic rate and decreased the intercelluar CO₂ concentration in strawberry leaves. Under DCMU treatment, trapping energy for Q_A reduction per PSII reaction center increased greatly, indicating DCMU inhibited electron transfer from Q_A ^-. The maximum...

Growth and ecophysiological response in juvenile clones of Guadua (Guaduinae: Bambusoideae) cultivated in an altered lowland tropical regionOriginal Papers

F. Ely, O. Araque, R. Jaimez

Photosynthetica 2017, 55(2):264-275 | DOI: 10.1007/s11099-016-0236-4

Guadua amplexifolia and Guadua angustifolia are the most promising timber substitutes amongst American bamboos due to their outstanding dimensions and structural properties. Despite the commercial potential of these species, there are few studies on the survival and adaptability of juveniles in plantations. The present study dealt with survival, growth, and ecophysiological response of juvenile clonal plants of these species, cultivated in abandoned pastures in Mérida, Venezuela. Survivorship, growth (height and culm diameter), and ecophysiological parameters were monitored the first year during wet and dry seasons. Survival rates were...