Responses of Leaf Hydraulic Traits of Schoenoplectus Tabernaemontani To Increasing Temperature and CO2 Concentrations

Abstract Background Against the background of a changing climate, the responses of functional traits of plateau wetland plants to increasing temperatures and CO2 concentrations need to be understood. Hydraulic traits are the key for plants to maintain their ecological functions and affect their growth and survival. However, few studies have comprehensively considered the response strategies of wetland plants' hydraulic traits to environmental changes in the context of water and matter transport, loss, and retention. According to the latest IPCC prediction results, we performed experiments under increased temperature (2℃) and CO2 levels (850 µmol/mol) in an artificial Sealed-top Chamber (STC) to investigate the responses of the hydraulic characteristics of Schoenoplectus tabernaemontani, the dominant species in plateau wetlands in China. Results Compared with the CK group, net photosynthetic rate, transpiration rate, stomatal length, cuticle thickness, vascular bundle length, vascular bundle width, and vascular bundle area of S. tabernaemontani in the ET group were significantly reduced, whereas stomatal density and vein density increased significantly. Compared with the CK group, the hydraulic traits of S. tabernaemontani in the EC group were reduced considerably in stomatal length and cuticle thickness but increased dramatically in stomatal density, and there were no significant differences between other parameter values and the control group. Net photosynthetic rate was significantly positively correlated with stomatal length, cuticle thickness, and vascular bundle length, and stomatal conductance was significantly positively correlated with cuticle thickness. The transpiration rate was significantly positively correlated with cuticle thickness, epidermal cell area, vascular bundle length, vascular bundle width, and vascular bundle area. Regarding the hydraulic traits, there was a significant negative correlation between stomatal density and stomatal length, or cuticle thickness, and a significant positive correlation between the latter two. The epidermal cell area was significantly positively correlated with epidermal thickness, vascular bundle length, vascular bundle width, and vascular bundle area Conclusions Increased temperature and CO2 levels are not conducive to the photosynthetic activity of S. tabernaemontani. Photosynthetic rate, stomatal density and size, vein density, epidermal structure size, and vascular bundle size play an essential role in the adaptation of this species to changes in temperature and CO2 concentration. In the process of adaptation, hydraulic traits are not isolated from each other, and there is a functional association among traits. This study provide a scientific basis for the management and protection of plateau wetlands.

Download Full-text

Response of in vitro Cultured Palm Oil Seedling Under Saline Condition to Elevated Carbon Dioxide and Photosynthetic Photon Flux Density

Annals of Tropical Research ◽

10.32945/atr3413.2012 ◽

2012 ◽

pp. 52-64

Author(s):

Pet Roey Pascual ◽

Krienkai Mosaleeyanon ◽

Kanokwan Romyanon ◽

Chalermpol Kirdmanee

Keyword(s):

Stomatal Conductance ◽

Net Photosynthetic Rate ◽

Elevated Co2 ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Pigment Contents ◽

Salinity Levels ◽

Oil Palms ◽

Ambient Co2

Salt stress elicits various physiological and growth responses of oil palm. A laboratory experiment was conducted to determine the responses of oil palms cultured in vitro under varying salinity levels (0, 85.5, 171.11, 342.21 and 684.43 mM NaCl) to elevated CO2 (1000 μmol CO2/mol) and PPFD (100±5 μmol m-2s-1) in terms of growth characteristics, pigment contents and photosynthetic abilities. After 14 days of culture, net photosynthetic rate (μmol CO2 m-2s-1) of oil palms across varying salinity levels was 5.33 times higher than those cultured under ambient CO, (380±100 Mmol CO2/mol) and PPFD (50±5 μmol m-2s -1). At increased net photosynthetic rate (elevated CO2 and PPFD), despite having no significant difference in pigment contents (chlorophyll a, chlorophyll b, total chlorophyll and carotenoid) between different CO2 and PPFD levels, dry weight and percent dry matter were 0.26 and 0.11 times higher, respectively, as compared to those cultured under ambient CO2 and PPFD. In the same elevated CO2 and PPFD level, across all salinity levels, stomatal conductance was 0.30 times lower than those cultured under ambient CO2 and PPFD. At reduced stomatal conductance (elevated CO2 and PPFD), transpiration rate was also reduced by 0.30 times. Thus with increased net photosynthetic rate and reduced transpiration rate, water use efficiency was increased by 7.22 times, across all salinity levels, than those cultured at ambient CO2 and PPFD. These were considered essential for NaCl produces iso-osmotic stress.

Download Full-text

Effects of the reciprocal grafting on the photosynthesis of two genotypes tomato offspring under selenium stress

E3S Web of Conferences ◽

10.1051/e3sconf/201913607008 ◽

2019 ◽

Vol 136 ◽

pp. 07008

Author(s):

Shiyao Shan ◽

Huizhong Luo ◽

Jinpeng Zhu ◽

Zhiyu Li ◽

Huanxiu Li

Keyword(s):

Stomatal Conductance ◽

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Functional Activity ◽

Theoretical Basis ◽

Photosynthetic Capacity ◽

Growth Characteristics ◽

Cherry Tomato ◽

Fresh Weight

To study the effects of the reciprocal grafting on the photosynthesis of two genotypes tomato offspring under selenium stress, red ball cherry tomato cherry 5-5-1 and yellow ball cherry tomato yellow RTY-3-2 post-grafting generation (red scion, red rootstock, yellow scion and yellow rootstock) and seedlings (red CK and yellow CK) planted in 10 mg·kg-1 selenium soil, and the pot experiment was carried out to study the effects of the reciprocal grafting on the growth characteristics and the photosynthesis of tomato offspring under selenium stress. The results showed that grafting increased the fresh weight of the organs of the offspring, the ratio of root to shoot, and the functional activity of the roots of the plants, which was conducive to the growth of tomato offspring. Simultaneously, it could effectively improve the photosynthetic capacity of grafted offspring leaves at the seedling stage. The grafted offspring of rootstocks had the best effect on improving the net photosynthetic rate, stomatal conductance and transpiration rate and stomatal conductance of tomato leaves, and decreased intercellular CO2 concentration. Among them, the best effect of yellow rootstock was to provide ideas and theoretical basis for the production of selenium-enriched tomatoes in the selenium-deficient areas in the future.

Download Full-text

Orange Rust Effects on Leaf Photosynthesis and Related Characters of Sugarcane

Plant Disease ◽

10.1094/pdis-10-10-0762 ◽

2011 ◽

Vol 95 (6) ◽

pp. 640-647 ◽

Cited By ~ 50

Author(s):

Duli Zhao ◽

Neil C. Glynn ◽

Barry Glaz ◽

Jack C. Comstock ◽

Sushma Sood

Keyword(s):

Stomatal Conductance ◽

Quantum Yield ◽

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Carbon Fixation ◽

Dark Respiration ◽

Western Hemisphere ◽

Maximum Quantum Yield ◽

Leaf Photosynthesis

Orange rust of sugarcane (Saccharum spp. hybrids), caused by Puccinia kuehnii, is a relatively new disease in the Western Hemisphere that substantially reduces yields in susceptible sugarcane genotypes. The objective of this study was to determine the physiological mechanisms of orange rust–induced reductions in sugarcane growth and yield by quantifying effects of the disease on leaf SPAD index (an indication of leaf chlorophyll content), net photosynthetic rate, dark respiration, maximum quantum yield of CO2 assimilation, carbon fixation efficiency, and the relationships between these leaf photosynthetic components and rust disease ratings. Plants growing in pots were inoculated with the orange rust pathogen using a leaf whorl inoculation method. A disease rating was assigned using a scale from 0 to 4 with intervals of 0.5. At disease ratings ≥2, the rust-infected leaf portion of inoculated plants showed significant reductions in SPAD index, maximum quantum yield, carbon fixation efficiency, stomatal conductance, leaf transpiration rate, and net photosynthetic rate; but the rusted portion of the infected leaves had increased intercellular CO2 concentration and leaf dark respiration rate. Although leaf SPAD index, photosynthetic rate, stomatal conductance, and transpiration rate at the rust-infected portion decreased linearly with increased rust rating, the effect of orange rust on photosynthetic rate was much greater than that on stomatal conductance and transpiration. Unlike earlier reports on other crops, reduction in leaf photosynthesis by orange rust under low light was greater than that under high light conditions. These results help improve the understanding of orange rust etiology and physiological bases of sugarcane yield loss caused by orange rust.

Download Full-text

Leaf Anatomical Adaptation Under Early Drought Stress of Sugarcane Cultivars – KKU-1999-02 and KKU-1999-03

Acta Agrobotanica ◽

10.5586/aa.7419 ◽

2021 ◽

Vol 74 ◽

Author(s):

Worasitikulya Taratima ◽

Thapakorn Ritmaha ◽

Nakorn Jongrungklang ◽

Pitakpong Maneerattanarungroj

Keyword(s):

Drought Stress ◽

Vascular Bundle ◽

Agronomic Traits ◽

Stomatal Density ◽

Breeding Programs ◽

Stomatal Size ◽

Anatomical Changes ◽

Drought Tolerant ◽

Cuticle Thickness ◽

Anatomical Adaptation

Abstract Anatomical adaptation is an important feature that allows plants to mitigate drought stress. A comparative leaf anatomy of two drought-tolerant sugarcane cultivars, KKU-1999-02 and KKU-1999-03, was studied in early drought stress between 30 and 90 days after planting using peeling and freehand sectioning methods. KKU-1999-02 and KKU-1999-03 showed different anatomical adaptation features, such as increase in cuticle thickness, bulliform cell size, vascular bundle, and stomatal density, and decreases in leaf thickness and stomatal size. KKU-1999-02 showed more remarkable anatomical changes than KKU-1999-03. The results provide important information that can be applied in combination with other agronomic traits in sugarcane breeding programs to expand the adaptation devices of tolerant cultivars under preliminary drought stress.

Download Full-text

Effect of Water Stress on Photosynthetic Parameters of Soybean (Glycine max) and Velvetleaf (Abutilon theophrasti)

Weed Science ◽

10.1017/s0043174500026722 ◽

1987 ◽

Vol 35 (1) ◽

pp. 15-21 ◽

Cited By ~ 16

Author(s):

Philip H. Munger ◽

James M. Chandler ◽

J. Tom Cothren

Keyword(s):

Glycine Max ◽

Water Stress ◽

Stomatal Conductance ◽

Water Potential ◽

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Abutilon Theophrasti ◽

Leaf Water ◽

Photosynthetic Parameters

Greenhouse experiments were conducted to elucidate the effects of water stress on photosynthetic parameters of soybean [Glycine max(L.) Merr. ‘Hutton′] and velvetleaf (Abutilon theophrastiMedik. # ABUTH). Stomatal conductance of both species responded curvilinearly to reductions in leaf water potential. At leaf water potentials less negative than −2.5 MPa, stomatal conductance, net photosynthetic rate, and transpiration rate were greater in velvetleaf than in soybean. Soybean photosynthetic rate was linearly related to stomatal conductance. Velvetleaf photosynthetic rate increased linearly with stomatal conductances up to 1.5 cm s–1; however, no increase in photosynthetic rate was observed at stomatal conductances greater than 1.5 cm s–1, indicating nonstomatal limitations to photosynthesis. As water stress intensified, stomatal conductance, photosynthetic rate, and transpiration of velvetleaf declined more rapidly than in soybean.

Download Full-text

Characterization of coffee cultivars leaf rust-resistant subjected to framework pruning

Coffee Science ◽

10.25186/cs.v13i1.1376 ◽

2018 ◽

Vol 13 (1) ◽

pp. 63 ◽

Cited By ~ 1

Author(s):

Estevam Antonio Chagas Reis ◽

Tainah Freitas ◽

Milene Alves de Figueiredo Carvalho ◽

Antônio Nazareno Guimarães Mendes ◽

Tiago Teruel Rezende ◽

...

Keyword(s):

Water Use Efficiency ◽

Net Photosynthetic Rate ◽

Leaf Rust ◽

Water Use ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Agronomic Traits ◽

High Yield ◽

Area Index ◽

Use Efficiency

The goal of our work was to evaluate physiological and agronomic traits, as well as the relationship between these traits in coffee cultivars coming from a germplasm supposedly resistant to leaf rust, and their response to framework pruning. The experiment was conducted at the Federal University of Lavras in randomized blocks with three replicates, with spacing of 3.5 x 0.7 m and plots of 12 plants. An amount of 25 coffee cultivars was evaluated, from which 23 were considered resistant and two susceptible to leaf rust. Traits analyzed were the plagiotropic branch length and number of nodes, net photosynthetic rate, transpiration rate, water use efficiency, fluorescence and chlorophyll index, leaf area index, leaf rust incidence and yield. Catucaí Amarelo 20/15 cv 479, Araponga MG1 and Tupi IAC 1669-33 cultivars show highly responsive to framework pruning. These cultivars have high yield associated to high net photosynthetic rate, water use efficiency and low transpiration rate. Moreover, the last two cultivars show a low incidence of leaf rust. The Acauã cultivar has a good response to framework pruning, showing high yield associated to lower incidence of leaf rust. Catucaí Vermelho 785/15 cultivar is not responsive to framework pruning because show lower yield, high incidence of leaf rust, low vegetative growth and low water use efficiency.

Download Full-text

Effects of canopy closure on photosynthetic characteristics of Ilex latifolia Thunb. in Phyllostachys pubescens forests

Research in Ecology ◽

10.30564/re.v2i2.1366 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Jianshuang Gao ◽

Shunyao Zhuang ◽

Zhuangzhuang Qian

Keyword(s):

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Photosynthetically Active Radiation ◽

Great Influence ◽

Light Response ◽

Photosynthetic Characteristics ◽

Phyllostachys Pubescens ◽

Canopy Closure ◽

Active Radiation

Plantation under the forest is a good way of agroforestry, but the canopy closure has a great influence on understory herbs’ growth. In the study, different canopy closures of Phyllostachys pubescens forests were set up to explore its influence on the growth of Ilex latifolia Thunb. The photosynthetic characteristics of Ilex latifolia leaves under different canopy closures were determined by Li-6400 portable photosynthetic system. The results showed that the net photosynthetic rate curve of Ilex latifolia leaves of T1 (canopy closure of 0.56) was bimodal with an obvious "midday depression" phenomenon, while the net photosynthetic rate curves of T2 (canopy closure of 0.72) and T3 (canopy closure of 0.86) were unimodal. The results of light response curve showed that the photosynthetically active radiation and transpiration rate reduced with the increasing of canopy closures. The photosynthetically active radiation, transpiration rate, stomatal conductance, and net photosynthetic rate of Ilex latifolia leaves of T2 were higher than those of T3. Although the net photosynthetic rate of T2 was lower than that of T1, it had no obvious photo-inhibition which affected plant growth. Overall, the canopy closure of 0.72 was more suitable for the growth of Ilex latifolia. The herb plantation in the bamboo forest should be considered with the canopy closure for a better growth.

Download Full-text

Light control of catechin accumulation is mediated by photosynthetic capacity in tea plant (Camellia sinensis)

BMC Plant Biology ◽

10.1186/s12870-021-03260-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ping Xiang ◽

Qiufang Zhu ◽

Marat Tukhvatshin ◽

Bosi Cheng ◽

Meng Tan ◽

...

Keyword(s):

Light Intensity ◽

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Photosynthetic Capacity ◽

Epigallocatechin Gallate ◽

Tea Plant ◽

High Light ◽

Light Intensities ◽

Tea Plants

Abstract Background Catechins are crucial in determining the flavour and health benefits of tea, but it remains unclear that how the light intensity regulates catechins biosynthesis. Therefore, we cultivated tea plants in a phytotron to elucidate the response mechanism of catechins biosynthesis to light intensity changes. Results In the 250 μmol·m− 2·s− 1 treatment, the contents of epigallocatechin, epigallocatechin gallate and total catechins were increased by 98.94, 14.5 and 13.0% respectively, compared with those in the 550 μmol·m− 2·s− 1 treatment. Meanwhile, the photosynthetic capacity was enhanced in the 250 μmol·m− 2·s− 1 treatment, including the electron transport rate, net photosynthetic rate, transpiration rate and expression of related genes (such as CspsbA, CspsbB, CspsbC, CspsbD, CsPsbR and CsGLK1). In contrast, the extremely low or high light intensity decreased the catechins accumulation and photosynthetic capacity of the tea plants. The comprehensive analysis revealed that the response of catechins biosynthesis to the light intensity was mediated by the photosynthetic capacity of the tea plants. Appropriately high light upregulated the expression of genes related to photosynthetic capacity to improve the net photosynthetic rate (Pn), transpiration rate (Tr), and electron transfer rate (ETR), which enhanced the contents of substrates for non-esterified catechins biosynthesis (such as EGC). Meanwhile, these photosynthetic capacity-related genes and gallic acid (GA) biosynthesis-related genes (CsaroB, CsaroDE1, CsaroDE2 and CsaroDE3) co-regulated the response of GA accumulation to light intensity. Eventually, the epigallocatechin gallate content was enhanced by the increased contents of its precursors (EGC and GA) and the upregulation of the CsSCPL gene. Conclusions In this study, the catechin content and photosynthetic capacity of tea plants increased under appropriately high light intensities (250 μmol·m− 2·s− 1 and 350 μmol·m− 2·s− 1) but decreased under extremely low or high light intensities (150 μmol·m− 2·s− 1 or 550 μmol·m− 2·s− 1). We found that the control of catechin accumulation by light intensity in tea plants is mediated by the plant photosynthetic capacity. The research provided useful information for improving catechins content and its light-intensity regulation mechanism in tea plant.

Download Full-text