High Temperature Acclimation of Leaf Gas Exchange, Photochemistry, and Metabolomic Profiles in Populus trichocarpa

Three species of herbaceous perennials were tested on their ability to withstand and recover from drought stress periods of 2, 4, and 6 days. Eupatorium rugosum and Boltonia asteroides `Snowbank' were chosen because of their reported drought intolerance, while Rudbeckia triloba was chosen based on its reported drought tolerance. Drought stress began on 19 Sept. 1997. Plants were transplanted into the field the day following the end of each stress period. The effects of drought on transpiration rate, stomatal conductance, and net photosynthetic rate were measured during the stress and throughout recovery using an infrared gas analysis system. Leaf gas exchange measurements were taken through recovery until there were no differences between the stressed plants and the control plants. Transpiration, stomatal conductance, and photosynthesis of Rudbeckia and Boltonia were not affected until 4 days after the start of stress. Transpiration of Eupatorium decreased after 3 days of stress. After rewatering, leaf gas exchange of Boltonia and Rudbeckia returned to non-stressed levels quicker than Eupatorium. Growth measurements were taken every other day during stress, and then weekly following transplanting. Measurements were taken until a killing frost that occurred on 3 Nov. There were no differences in the growth between the stressed and non-stressed plants in any of the species. Plants will be monitored throughout the winter, spring, and summer to determine the effects of drought on overwintering capability and regrowth.

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Grapevine species from varied native habitats exhibit differences in embolism formation/repair associated with leaf gas exchange and root pressure

Plant Cell & Environment ◽

10.1111/pce.12497 ◽

2015 ◽

Vol 38 (8) ◽

pp. 1503-1513 ◽

Cited By ~ 53

Author(s):

THORSTEN KNIPFER ◽

ASHLEY EUSTIS ◽

CRAIG BRODERSEN ◽

ANDREW M. WALKER ◽

ANDREW J. MCELRONE

Keyword(s):

Gas Exchange ◽

Leaf Gas Exchange ◽

Root Pressure ◽

Native Habitats

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An improved theory for calculating leaf gas exchange more precisely accounting for small fluxes

Nature Plants ◽

10.1038/s41477-021-00861-w ◽

2021 ◽

Author(s):

Diego A. Márquez ◽

Hilary Stuart-Williams ◽

Graham D. Farquhar

Keyword(s):

Gas Exchange ◽

Leaf Gas Exchange

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Long-term liming improves soil fertility and soybean root growth, reflecting improvements in leaf gas exchange and grain yield

European Journal of Agronomy ◽

10.1016/j.eja.2021.126308 ◽

2021 ◽

Vol 128 ◽

pp. 126308

Author(s):

João William Bossolani ◽

Carlos Alexandre Costa Crusciol ◽

José Roberto Portugal ◽

Luiz Gustavo Moretti ◽

Ariani Garcia ◽

...

Keyword(s):

Gas Exchange ◽

Root Growth ◽

Soil Fertility ◽

Grain Yield ◽

Leaf Gas Exchange ◽

Soybean Root

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Shading Effects on Leaf Gas Exchange, Leaf Pigments and Secondary Metabolites of Polygonum minus Huds., an Aromatic Medicinal Herb

Plants ◽

10.3390/plants10030608 ◽

2021 ◽

Vol 10 (3) ◽

pp. 608

Author(s):

Fairuz Fatini Mohd Yusof ◽

Jamilah Syafawati Yaacob ◽

Normaniza Osman ◽

Mohd Hafiz Ibrahim ◽

Wan Abd Al Qadr Imad Wan-Mohtar ◽

...

Keyword(s):

Gas Exchange ◽

Secondary Metabolites ◽

Chlorophyll A ◽

Leaf Gas Exchange ◽

Photosynthesis Rate ◽

Total Phenolic ◽

Chlorophyll B ◽

Low Light ◽

Total Anthocyanin ◽

Polygonum Minus

The growing demand for high value aromatic herb Polygonum minus-based products have increased in recent years, for its antioxidant, anticancer, antimicrobial, and anti-inflammatory potentials. Although few reports have indicated the chemical profiles and antioxidative effects of Polygonum minus, no study has been conducted to assess the benefits of micro-environmental manipulation (different shading levels) on the growth, leaf gas exchange and secondary metabolites in Polygonum minus. Therefore, two shading levels (50%:T2 and 70%:T3) and one absolute control (0%:T1) were studied under eight weeks and 16 weeks of exposures on Polygonum minus after two weeks. It was found that P. minus under T2 obtained the highest photosynthesis rate (14.892 µmol CO2 m−2 s−1), followed by T3 = T1. The increase in photosynthesis rate was contributed by the enhancement of the leaf pigments content (chlorophyll a and chlorophyll b). This was shown by the positive significant correlations observed between photosynthesis rate with chlorophyll a (r2 = 0.536; p ≤ 0.05) and chlorophyll b (r2 = 0.540; p ≤ 0.05). As the shading levels and time interval increased, the production of total anthocyanin content (TAC) and antioxidant properties of Ferric Reducing Antioxidant Power (FRAP) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) also increased. The total phenolic content (TPC) and total flavonoid content (TFC) were also significantly enhanced under T2 and T3. The current study suggested that P.minus induce the production of more leaf pigments and secondary metabolites as their special adaptation mechanism under low light condition. Although the biomass was affected under low light, the purpose of conducting the study to boost the bioactive properties in Polygonum minus has been fulfilled by 50% shading under 16 weeks’ exposure.

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Ethylene enhances root water transport and aquaporin expression in trembling aspen (Populus tremuloides) exposed to root hypoxia

BMC Plant Biology ◽

10.1186/s12870-021-02995-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xiangfeng Tan ◽

Mengmeng Liu ◽

Ning Du ◽

Janusz J. Zwiazek

Keyword(s):

Gas Exchange ◽

Water Transport ◽

Populus Tremuloides ◽

Leaf Gas Exchange ◽

Hydraulic Conductance ◽

Root Hydraulic Conductance ◽

Trembling Aspen ◽

Expression Levels ◽

Root Hypoxia ◽

Exogenous Ethylene

Abstract Background Root hypoxia has detrimental effects on physiological processes and growth in most plants. The effects of hypoxia can be partly alleviated by ethylene. However, the tolerance mechanisms contributing to the ethylene-mediated hypoxia tolerance in plants remain poorly understood. Results In this study, we examined the effects of root hypoxia and exogenous ethylene treatments on leaf gas exchange, root hydraulic conductance, and the expression levels of several aquaporins of the plasma membrane intrinsic protein group (PIP) in trembling aspen (Populus tremuloides) seedlings. Ethylene enhanced net photosynthetic rates, transpiration rates, and root hydraulic conductance in hypoxic plants. Of the two subgroups of PIPs (PIP1 and PIP2), the protein abundance of PIP2s and the transcript abundance of PIP2;4 and PIP2;5 were higher in ethylene-treated trembling aspen roots compared with non-treated roots under hypoxia. The increases in the expression levels of these aquaporins could potentially facilitate root water transport. The enhanced root water transport by ethylene was likely responsible for the increase in leaf gas exchange of the hypoxic plants. Conclusions Exogenous ethylene enhanced root water transport and the expression levels of PIP2;4 and PIP2;5 in hypoxic roots of trembling aspen. The results suggest that ethylene facilitates the aquaporin-mediated water transport in plants exposed to root hypoxia.

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