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Zhou J, Cheng K, Huang G, Chen G, Zhou S, Huang Y, Zhang J, Duan H, Fan H. Effects of exogenous 3-indoleacetic acid and cadmium stress on the physiological and biochemical characteristics of Cinnamomum camphora. Ecotoxicol Environ Saf 2020; 191:109998. [PMID: 31796252 DOI: 10.1016/j.ecoenv.2019.109998] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/13/2019] [Accepted: 11/22/2019] [Indexed: 05/22/2023]
Abstract
Indoleacetic acid (IAA) is a plant growth regulator that plays an important role in plant growth and development, and participates in the regulation of abiotic stress. To explore the effect of IAA on cadmium toxicity in Cinnamomum camphora, an indoor potted experiment was conducted with one-year-old C. camphora seedlings. The influence of IAA on cadmium accumulation, net photosynthetic rates, respiration, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll and carotenoids), osmoregulatory substances (proline, soluble sugar and soluble protein) and the malondialdehyde content in C. camphora leaves treated with 30 mg kg-1 cadmium was analysed with or without the addition of 10 mg kg-1 IAA. Cadmium accumulation in the leaves of C. camphora with the addition of exogenous IAA was significantly higher than accumulation during cadmium stress without additional IAA (ca 69.10% after 60 days' incubation). During the culture period, the net photosynthetic rate in C. camphora leaves subjected to cadmium stress without the addition of IAA was up to 24.31% lower than that of control plants. The net photosynthetic rate in C. camphora leaves subjected to cadmium stress and addition of IAA was up to 30.31% higher than that of leaves subjected to cadmium stress without the addition of IAA. Chlorophyll a, total chlorophyll and carotenoid contents in the cadmium-stressed leaves without the addition of IAA were lower than those in the control treatment. The presence of IAA increased the chlorophyll a, total chlorophyll and carotenoid contents relative to the cadmium stress without the addition of IAA. The respiration rate and concentrations of proline, soluble sugar, soluble protein and malondialdehyde in C. camphora leaves subjected to cadmium stress without the addition of IAA were higher than those in the control. The addition of IAA reduced the respiration rate, and the concentrations of proline, soluble sugar, soluble protein and malondialdehyde in C. camphora leaves when compared with the cadmium stress without the addition of IAA. These results indicate that exogenous IAA improves photosynthetic performance and the growth environment of C. camphora by enhancing the net photosynthetic rate, increasing concentrations of osmoregulatory substances, removing reactive oxygen radicals and eliminating potential damage, thereby reducing the toxic effects of cadmium on C. camphora.
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Affiliation(s)
- Jihai Zhou
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, 241000, China; Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China; Research Institute of Subtropical Forestry, Key Laboratory of Tree Breeding of Zhejiang Province, Hangzhou, 311400, China.
| | - Kun Cheng
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China
| | - Guomin Huang
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China
| | - Guangcai Chen
- Research Institute of Subtropical Forestry, Key Laboratory of Tree Breeding of Zhejiang Province, Hangzhou, 311400, China
| | - Shoubiao Zhou
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
| | - Yongjie Huang
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Jie Zhang
- Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources, College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Honglang Duan
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China
| | - Houbao Fan
- Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang, 330099, China
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Pan L, Lie GW, Xue L, Chen HY. Changes of Cinnamomum camphora root characteristics and soil properties under ozone stress in South China. Environ Sci Pollut Res Int 2019; 26:30684-30692. [PMID: 31049865 DOI: 10.1007/s11356-019-05199-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
High O3 exposure affects the forest growth and soil characteristics. Although there is substantial evidence that O3 does impose a stress on forest trees, the effects of O3 on roots and soil of evergreen broad-leaved tree species in South China remain unknown. The effects of ozone (O3) fumigation on the root biomass, root morphology, root nutrient, soil physical, and chemical properties were examined in Cinnamomum camphora seedlings grown under four O3 treatments (charcoal-filtered air (CF) or O3 at 1×, 2× and 4× ambient concentration). O3 significantly decreased root biomass and root carbon (C). Regardless of O3 level, elevated O3 significantly resulted in reduced root surface area, volume, number of forks, and specific root length (SRL). The percentages of fine to total root in terms of root surface area and root volume of seedlings under the CF and 1 × O3 treatments were significantly higher than those of seedlings under the 4 × O3 treatment, indicating that high O3 level impaired the growth performance of fine roots. O3 affected root growth and structures, which increased soil bulk density and reduced soil total porosity and void ratio. The soil pH under all O3 fumigation treatments significantly increased compared with CF treatment, whereas the organic matter significantly decreased. In conclusion, although the increased O3 level enhanced root N and P under 2 and 4 × O3 treatments compared with 1 × O3 treatment as compensation mechanisms to prevent O3-induced decrease in root C gain and root functions, O3 still decreased the root biomass and root tips, and changed the soil physical and chemical properties.
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Affiliation(s)
- Lan Pan
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
| | - Gan-Wen Lie
- Guangdong Eco-Engineering Polytechnic, Guangzhou, 510520, People's Republic of China
| | - Li Xue
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
| | - Hong-Yue Chen
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, People's Republic of China
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Du L, Li Y, Yao Y, Zhang L. An Efficient Protocol for Plantlet Regeneration via Direct Organogenesis by Using Nodal Segments from Embryo-Cultured Seedlings of Cinnamomum camphora L. PLoS One 2015; 10:e0127215. [PMID: 25962170 PMCID: PMC4427331 DOI: 10.1371/journal.pone.0127215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 04/13/2015] [Indexed: 11/19/2022] Open
Abstract
A simple and efficient plantlet regeneration protocol via direct organogenesis was established for camphor tree (Cinnamomum camphora L.). Stem segments with one node (SN explants) from embryo-cultured seedlings (EC seedlings) were used as explants. Murashige and Skoog (MS) medium supplemented with 0.5 mg/L 2, 4-dichlorophenoxyacetic acid and 2.0 mg/L 6-benzyladenine was used to induce cotyledonary embryo germination. This medium was also used for EC seedlings propagation and adventitious bud induction from SN explants. Regenerated plantlets were cultured on hormone-free MS medium for elongation and root induction. The regeneration capability of SN explants was compared by using EC seedling lines established in this research. EC seedling line EL6 exhibited the highest adventitious bud induction frequency (91.7%) and the highest number of buds per responding explant (5.2), which was considered as the most efficient EC seedling line for further gene transformation research.
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Affiliation(s)
- Li Du
- School of Life Science and Technology, Nanyang Normal University, Nanyang City, Henan Province, P. R. China
- * E-mail:
| | - Yongpeng Li
- School of Life Science and Technology, Nanyang Normal University, Nanyang City, Henan Province, P. R. China
| | - Yao Yao
- School of Life Science and Technology, Nanyang Normal University, Nanyang City, Henan Province, P. R. China
| | - Liwei Zhang
- School of Life Science and Technology, Nanyang Normal University, Nanyang City, Henan Province, P. R. China
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Niu J, Feng Z, Zhang W, Zhao P, Wang X. Non-stomatal limitation to photosynthesis in Cinnamomum camphora seedings exposed to elevated O3. PLoS One 2014; 9:e98572. [PMID: 24892748 PMCID: PMC4043779 DOI: 10.1371/journal.pone.0098572] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 05/04/2014] [Indexed: 11/26/2022] Open
Abstract
Ozone (O3) is the most phytotoxic air pollutant for global forests, with decreased photosynthesis widely regarded as one of its most common effects. However, controversy exists concerning the mechanism that underlies the depressing effects of O3 on CO2 assimilation. In the present study, seedlings of Cinnamomum camphora, a subtropical evergreen tree species that has rarely been studied, were exposed to ambient air (AA), ambient air plus 60 [ppb] O3 (AA+60), or ambient air plus 120 [ppb] O3 (AA+120) in open-top chambers (OTCs) for 2 years. Photosynthetic CO2 exchange and chlorophyll a fluorescence were investigated in the second growing season (2010). We aim to determine whether stomatal or non-stomatal limitation is responsible for the photosynthesis reduction and to explore the potential implications for forest ecosystem functions. Results indicate that elevated O3 (E-O3) reduced the net photosynthetic rates (PN) by 6.0-32.2%, with significant differences between AA+60 and AA+120 and across the four measurement campaigns (MCs). The actual photochemical efficiency of photosystem II (PSII) in saturated light (Fv'/Fm') was also significantly decreased by E-O3, as was the effective quantum yield of PSII photochemistry (ΦPSII). Moreover, E-O3 significantly and negatively impacted the maximum rates of carboxylation (Vcmax) and electron transport (Jmax). Although neither the stomatal conductance (gs) nor the intercellular CO2 concentration (Ci) was decreased by E-O3, PN/gs was significantly reduced. Therefore, the observed reduction in PN in the present study should not be attributed to the unavailability of CO2 due to stomatal limitation, but rather to the O3-induced damage to Ribulose-1,5-bisphosphate carboxylase/oxygenase and the photochemical apparatus. This suggests that the down-regulation of stomatal conductance could fail to occur, and the biochemical processes in protoplasts would become more susceptible to injuries under long-term O3 exposure, which may have important consequences for forest carbon and water budget.
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Affiliation(s)
- Junfeng Niu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Zhaozhong Feng
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Weiwei Zhang
- Key Laboratory of Black Soil Ecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, Heilongjiang, China
| | - Ping Zhao
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Xiaoke Wang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
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Zhang W, Feng Z, Wang X, Niu J. Responses of native broadleaved woody species to elevated ozone in subtropical China. Environ Pollut 2012; 163:149-57. [PMID: 22325443 DOI: 10.1016/j.envpol.2011.12.035] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 12/10/2011] [Accepted: 12/15/2011] [Indexed: 05/10/2023]
Abstract
To assess ozone sensitivity of subtropical broadleaved tree species and explore possible underlying mechanisms, six evergreen and two deciduous native species were exposed to either charcoal-filtered air or elevated O(3) (E-O(3), ∼150ppb) for one growing season. Initial visible symptoms in deciduous species appeared much earlier than those in evergreen species. The species which first showed visible symptoms also had the largest reductions in biomass. E-O(3) induced significant decreases in photosynthesis rate, chlorophyll content and antioxidant capacity but a significant increase in malondialdehyde content in two deciduous species and two evergreen species (Cinnamomum camphora and Cyclobalanopsis glauca). Except C. glauca, however, E-O(3) had no significant effects on stomatal conductance (g(s)), total phenols and ascorbate contents. Difference in O(3) sensitivity among all species was strongly attributed to specific leaf mass rather than g(s). It suggests that some subtropical tree species will be threatened by rising O(3) concentrations in the near future.
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Affiliation(s)
- Weiwei Zhang
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 2871 Mailbox, Shuangqing Road 18, Haidian District, Beijing 100085, China
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Osawa H, Endo I, Hara Y, Matsushima Y, Tange T. Transient proliferation of proanthocyanidin-accumulating cells on the epidermal apex contributes to highly aluminum-resistant root elongation in camphor tree. Plant Physiol 2011; 155:433-46. [PMID: 21045123 PMCID: PMC3075795 DOI: 10.1104/pp.110.166967] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 10/26/2010] [Indexed: 05/22/2023]
Abstract
Aluminum (Al) is a harmful element that rapidly inhibits the elongation of plant roots in acidic soils. The release of organic anions explains Al resistance in annual crops, but the mechanisms that are responsible for superior Al resistance in some woody plants remain unclear. We examined cell properties at the surface layer of the root apex in the camphor tree (Cinnamomum camphora) to understand its high Al resistance mechanism. Exposure to 500 μm Al for 8 d, more than 20-fold higher concentration and longer duration than what soybean (Glycine max) can tolerate, only reduced root elongation in the camphor tree to 64% of the control despite the slight induction of citrate release. In addition, Al content in the root apices was maintained at low levels. Histochemical profiling revealed that proanthocyanidin (PA)-accumulating cells were present at the adjacent outer layer of epidermis cells at the root apex, having distinctive zones for cell division and the early phase of cell expansion. Then the PA cells were gradually detached off the root, leaving thin debris behind, and the root surface was replaced with the elongating epidermis cells at the 3- to 4-mm region behind the tip. Al did not affect the proliferation of PA cells or epidermis cells, except for the delay in the start of expansion and the accelerated detachment of the former. In soybean roots, the innermost lateral root cap cells were absent in both PA accumulation and active cell division and failed to protect the epidermal cell expansion at 25 μm Al. These results suggest that transient proliferation and detachment of PA cells may facilitate the expansion of epidermis cells away from Al during root elongation in camphor tree.
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Affiliation(s)
- Hiroki Osawa
- Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
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Chen ZM, Chen YX, Du GJ, Wu XL, Li F. Effects of 60-day NO2 fumigation on growth, oxidative stress and antioxidative response in Cinnamomum camphora seedlings. J Zhejiang Univ Sci B 2010; 11:190-9. [PMID: 20205305 PMCID: PMC2833403 DOI: 10.1631/jzus.b0910350] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2009] [Accepted: 08/31/2009] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide (NO(2)) fumigation. METHODS Measurements were made up of the growth, chlorophyll content, chlorophyll fluorescence, antioxidant system and lipid peroxidation of one-year-old C. camphora seedlings exposed to NO(2) (0.1, 0.5, and 4 microl/L) fumigation in open top chambers over a period of 60 d. RESULTS After the first 30 d, 0.5 and 4.0 microl/L NO(2) showed insignificant effects on the growth of C. camphora seedlings. However, exposure to 0.5 and 4.0 microl/L NO(2) for 15 d significantly reduced their chlorophyll content (P<0.05), enhanced their malondialdehyde (MDA) content and superoxide dismutase (SOD) activity (P<0.05), and also significantly reduced the maximal quantum yield of PSII in the dark [the ratio of variable fluorescence to maximal fluorescence (F(v)/F(m))] (P<0.05). In the latter 30 d, 0.5 microl/L NO(2) showed a positive effect on the vitality of the seedlings, which was reflected by a recovery in the ratio of F(v)/F(m) and chlorophyll content, and obviously enhanced growth, SOD activity, ascorbate (AsA) content and glutathione reductase (GR) activity (P<0.05); 4.0 microl/L NO(2) then showed a negative effect, indicated by significant reductions in chlorophyll content and the ratio of F(v)/F(m), and inhibited growth (P<0.05). CONCLUSION The results suggest adaptation of C. camphora seedlings to 60-d exposure to 0.1 and 0.5 microl/L NO(2), but not to 60-d exposure to 4.0 microl/L NO(2). C. camphora seedlings may protect themselves from injury by strengthening their antioxidant system in response to NO(2)-induced oxidative stress.
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Affiliation(s)
- Zhuo-mei Chen
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China
- Zhejiang Forestry Academy, Hangzhou 310023, China
| | - Ying-xu Chen
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China
| | - Guo-jian Du
- Zhejiang Forestry Academy, Hangzhou 310023, China
| | - Xi-lin Wu
- Department of Geography, Minjiang University, Fuzhou 350108, China
| | - Feng Li
- Zhejiang Forestry Academy, Hangzhou 310023, China
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Zhuo CM, Chen YX, Du GJ. [Effects of NO2 on Cinnamomum camphora seedlings growth and photosynthesis]. Ying Yong Sheng Tai Xue Bao 2009; 20:1650-1656. [PMID: 19899466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A 2-month fumigation experiment was conducted with opened top chambers to study the effects of different concentration (0.1, 0.5, and 4.0 microl x L(-1)) NO2 on the growth and photosynthesis of 1-year Cinnamomum camphora seedlings. Fumigation with 0.1 and 0.5 microl NO2 x L(-1) promoted the growth of the seedlings, while with 4.0 microl NO2 x L(-1) was in adverse. The diurnal variation of net photosynthetic rate (P(n)) presented two-peaks, with an obvious depression in midday. 0.5 microl NO2 x L(-1) increased the P(n), the maximum of P(n) reached 8.542 micromol CO2 x m(-2) s(-1); 4.0 microl NO2 x L(-1) decreased the P(n) in most period of time; while the effect of 0.1 microl NO2 x L(-1) varied with time period. Fumigation with 0.5 and 4.0 microl NO2 x L(-1) increased the maximal and minimal values of stomatal conductance (G(s)) and intercellular CO2 concentration (C( i)), while 0.1 microl NO2 x L(-1) increased the maximal and minimal values of C(i) but decreased the maximal and minimal values of G(s). At the middle and late stages of fumigation, the mean P(n) of the seedlings treated with 0.5 microl NO2 x L(-1) was significantly higher than that treated with 0.1 and 4 microl NO2 x L(-1). At the early stage of fumigation, 0.5 and 4.0 micro NO2 x L(-1) significantly decreased the maximal PS II efficiency (F(v)/F(m)); and at the late stage, 4.0 microl NO2 x L(-1) still decreased the F(v)/F(m) significantly.
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Affiliation(s)
- Chen-Mei Zhuo
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310029, China.
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