Beneficial Effect of Exogenously Applied Calcium Chloride on the Anatomy and Fast Chlorophyll Fluorescence in Rhododendron × pulchrum Leaves Following Short-Term Heat Stress Treatment
Abstract
:1. Introduction
2. Materials and Methods
2.1. Plant Material
2.2. Microstructure of the Leaves and Ultrastructure of Leaf Epidermal Cells
2.3. Measurement of PF, DF and MR Kinetics
2.4. Statistical Analysis
3. Results
3.1. Phenotype and Microstructure of the Leaf
3.2. Ultrastructure of Leaf Epidermal Cells and Stomata
3.3. Analysis of PF, DF and MR Kinetics
4. Discussion
4.1. Exogenous CaCl2 Influences Leaf Structure under Heat Stress
4.2. Exogenous CaCl2 Influences Leaf Chlorophyll Fluorescence in R. × pulchrum under Heat Stress
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Abbreviations
References
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Group | Upper Epidermis Thickness (μm) | Palisade Thickness (μm) | Spongy Thickness (μm) | Lower Epidermis (μm) | Leaf Thickness (μm) | Ratio of Palisade Thickness to Spongy Thickness | Ratio of Palisade Thickness to Leaf Thickness |
---|---|---|---|---|---|---|---|
CK + W | 14.96 ± 1.79 b 1 | 33.47 ± 2.51 a | 39.58 ± 1.76 c | 12.27 ± 1.39 b | 100.28 ± 3.23 b | 0.85 ± 0.09 a | 0.33 ± 0.02 a |
H + W | 11.82 ± 1.70 c | 32.53 ± 3.53 a | 43.69 ± 6.36 c | 10.78 ± 2.25 b | 98.82 ± 9.84 b | 0.75 ± 0.08 b | 0.33 ± 0.02 a |
CK + Ca2+ | 22.62 ± 3.43 a | 31.81 ± 4.25 a | 53.78 ± 3.32 b | 17.29 ± 3.31 a | 125.53 ± 5.36 a | 0.59 ± 0.10 c | 0.25 ± 0.03 b |
H + Ca2+ | 15.40 ± 1.53 b | 22.67 ± 6.17 b | 65.91 ± 3.13 a | 13.25 ± 2.90 b | 117.23 ± 6.80 a | 0.34 ± 0.09 d | 0.19 ± 0.04 c |
Group | Cell Density (No. of Upper Epidermises/mm2) | Stomatal Density (No. of Stomata/mm2) | Stomatal Transverse Diameter/μm | Stomatal Longitudinal Diameter/μm | Stomatal Aperture/μm2 | Open Stomatal Density (No. of Opened Stomata/mm2) | Closed Stomatal Density (No. of Closed Stomata/mm2) | Ratio of Closed/Open Stomata |
---|---|---|---|---|---|---|---|---|
CK + W | 217 ± 5 b 1 | 71 ± 3 a | 5.56 ± 0.46 b | 1.43 ± 0.21 b | 6.23 ± 0.99 b | 57 ± 5 a | 14 ± 3 a | 0.25 ± 0.06 b |
H + W | 81 ± 6 d | 27 ± 3 c | 4.44 ± 0.71 c | 1.44 ± 0.27 b | 4.95 ± 0.78 b | 19 ± 3 c | 8 ± 1 b | 0.43 ± 0.07 a |
CK + Ca2+ | 104 ± 8 c | 46 ± 6 b | 7.38 ± 1.23 a | 2.31 ± 0.37 a | 13.55 ± 3.85 a | 45 ± 5 b | 1 ± 1 c | 0.03 ± 0.01 c |
H + Ca2+ | 251 ± 8 a | 57 ± 5 b | 8.02 ± 0.56 a | 2.39 ± 0.24 a | 15.03 ± 1.71 a | 57 ± 4 a | 1 ± 0 c | 0.02 ± 0.00 c |
Group | Fv/Fm 1 | PIABS 2 | ΨEo 3 | σRo 4 | γRC 5 | φEo 6 | φRo 7 | φDo 8 |
---|---|---|---|---|---|---|---|---|
CK + W | 0.80 ± 0.01 a 9 | 5.16 ± 0.44 a | 0.61 ± 0.06 a | 0.20 ± 0.04 a | 0.38 ± 0.03 a | 0.49 ± 0.06 a | 0.10 ± 0.02 bc | 0.20 ± 0.01 b |
CK + Ca2+ | 0.80 ± 0.02 a | 5.44 ± 0.16 a | 0.63 ± 0.07 a | 0.25 ± 0.02 a | 0.37 ± 0.03 ab | 0.50 ± 0.06 a | 0.13 ± 0.01 a | 0.20 ± 0.02 b |
H + W | 0.75 ± 0.03 b | 2.57 ± 0.47 b | 0.55 ± 0.12 a | 0.22 ± 0.09 a | 0.30 ± 0.04 b | 0.41 ± 0.10 a | 0.08 ± 0.02 c | 0.25 ± 0.03 a |
H + Ca2+ | 0.79 ± 0.02 ab | 4.72 ± 0.97 a | 0.63 ± 0.04 a | 0.24 ± 0.02 a | 0.36 ± 0.04 ab | 0.50 ± 0.05 a | 0.12 ± 0.00 ab | 0.21 ± 0.02 ab |
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Shen, J.; Cheng, H.; Li, X.; Pan, X.; Hu, Y.; Jin, S. Beneficial Effect of Exogenously Applied Calcium Chloride on the Anatomy and Fast Chlorophyll Fluorescence in Rhododendron × pulchrum Leaves Following Short-Term Heat Stress Treatment. Agronomy 2022, 12, 3226. https://doi.org/10.3390/agronomy12123226
Shen J, Cheng H, Li X, Pan X, Hu Y, Jin S. Beneficial Effect of Exogenously Applied Calcium Chloride on the Anatomy and Fast Chlorophyll Fluorescence in Rhododendron × pulchrum Leaves Following Short-Term Heat Stress Treatment. Agronomy. 2022; 12(12):3226. https://doi.org/10.3390/agronomy12123226
Chicago/Turabian StyleShen, Jianshuang, Hefeng Cheng, Xueqin Li, Xiangdong Pan, Yue Hu, and Songheng Jin. 2022. "Beneficial Effect of Exogenously Applied Calcium Chloride on the Anatomy and Fast Chlorophyll Fluorescence in Rhododendron × pulchrum Leaves Following Short-Term Heat Stress Treatment" Agronomy 12, no. 12: 3226. https://doi.org/10.3390/agronomy12123226