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Natural Product Research: Formerly Natural Product Letters Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gnpl20
Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus a
a
a
Matin Arefifard , Majid Mahdieh & Mohammadreza Amirjani a
Biological Department, Arak University, Arak, Iran Published online: 28 May 2014.
To cite this article: Matin Arefifard, Majid Mahdieh & Mohammadreza Amirjani (2014) Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus, Natural Product Research: Formerly Natural Product Letters, 28:18, 1499-1502, DOI: 10.1080/14786419.2014.913240 To link to this article: http://dx.doi.org/10.1080/14786419.2014.913240
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Natural Product Research, 2014 Vol. 28, No. 18, 1499–1502, http://dx.doi.org/10.1080/14786419.2014.913240
SHORT COMMUNICATION Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus Matin Arefifard*, Majid Mahdieh and Mohammadreza Amirjani Biological Department, Arak University, Arak, Iran
Downloaded by [RMIT University] at 03:51 03 September 2014
(Received 24 November 2013; final version received 6 April 2014) Plants, in their life cycle, are usually exposed to various kinds of non-biological stresses including heavy metals. One of these heavy metals is nickel which affects many physiological processes of plants. Studies have shown that the changes in planting conditions can affect the qualitative and quantitative features of Catharanthus roseus; therefore, creating stressful conditions (e.g. NiCl2) can be an effective way to investigate the changes. In this research, we investigated the effect of 0, 2.5, 5, 10, 25 and 50 mM concentrations of NiCl2 on the degree of catalase enzyme activity, amount of proline aggregation and photosynthetic parameters on seeds of pink variety of C. roseus. The results indicated that the degree of catalase enzyme activity and the amount of proline aggregation increased in plants which were exposed to NiCl2 treatments, especially in high concentrations, while the total protein decreased. The stress of Ni also affected photosynthetic parameters, and decreased the amount of pigments, as well as the efficiency of photosystem II. Keywords: Catharanthus roseus; nickel heavy metal; catalase; photosynthetic parameters
1. Introduction Plants, in their life cycle, are usually exposed to various kinds of non-biological stresses including heavy metals. The main compounds of mineral pollution are heavy metals (Cunningham & Ow 1996), and their effects depend on many factors such as environmental conditions, pH, organic materials and resistance of variations of plants (Eliwa 2000; Abbas & Kamel 2004). Heavy metals decrease the absorption and transfer of water, because of the downsizing of leaves’ surface (Azmat et al. 2006) which also affects photosynthesis (Haider et al. 2006). The aggregation of proline decreases the harm to the membrane and proteins (Verma 1999). Proline reduces the danger of free radicals by preventing lipid peroxidation. It adjusts the acidity of cytosol and maintains the consistency of NADþ/NADH (Sivakumar et al. 2000). Non-biological stresses alter the production of some proteins which is usually accompanied by the decrease in total protein (Ericson & Alfinito 1984; Alia & Saradhi 1991). The density ratio of metals in plants’ shoot to their root in those which are of high accumulators is more than one less accumulator ones (McGrath et al. 2002). Studies have shown that change in the planting conditions can affect the growth and qualitative and quantitative features of plants including Catharanthus roseus (periwinkle) (2n ¼ 16). The genus Catharanthus belongs to the family Apocynaceae. The growth of the plant is low in the early period of planting, and it has a long period of growth. A small amount of nickel, a heavy element, plays a significant role in nitrogen metabolism and the growth of plants, including C. roseus. Nowadays, nickel has been added to the collection of low consumed elements necessary for plants (Witte-Claus et al. 2002;
*Corresponding author. Email: [email protected] q 2014 Taylor & Francis
1500
M. Arefifard et al.
Benaroya et al. 2004). Among its first poisonous effects is peroxidation of membrane lipids which occurs through activation of lipo-oxygenase enzyme. Then, growth of the plant is controlled by change in the structure of cell membrane. In order to investigate the effect of nickel on C. roseus plant, at concentrations of 0, 2.5, 5, 10, 25 and 50 mM of nickel chloride, an experiment was conducted with factorial design, repeated three times in the Physiology Laboratory of Faculty of Sciences, University of Arak, Iran. The purpose of this study was to investigate the effect of different concentrations of nickel on some phytochemical features such as the amount of chlorophyll, proline, protein and the activity of antioxidant enzymes.
Downloaded by [RMIT University] at 03:51 03 September 2014
2. Results and discussion The statistical design was completely random. The graphs were drawn by using EXCEL, and the analysis of factors was done by using the SPSS software, version 11. The Duncan method was applied in order to compare the means of the obtained data and one-way analysis of variance. 2.1. Proline The amount of proline in the shoot of the plants treated with nickel chloride displayed significant increases compared with control sample (P , 0.001) (Figure S1). The accumulation of proline in plants exposed to heavy metal stress1 decreases the harmful effect on their membrane and proteins (Verma 1999). The increase of proline is because of decrease in analysis was proline decreased, increase in production, decrease in its consumption, and protein hydrolysis (Charest & Phan 1990). Heavy elements cause the decrease in the transfer chain of electron and the accumulation of NADH and Hþ. The production of proline through glutamic acid causes the decrease of accumulated NADH in cells (Venekemp 1989). 2.2. The catalase enzyme activity Nickel chloride did not have a significant effect on catalase activity. The amount of catalase in 50 mM treatment was 1.47 times more than in the control sample (H2O2 used per each mg of total protein per min) (Figure S2). One of the active types of oxygen H2O2 is produced in oxidative reactions in mitochondria and chloroplast (Neill et al. 2002). In the presence of iron iodine, peroxide hydrogen produces free radicals of oxygen (OH*). Peroxide hydrogen turns to water in the cell by catalase enzymes, ascorbate peroxidase and glutathione peroxidase (Scandalios 1993). The activity of the omitting enzymes of reactive oxygen species such as, catalase increases in nonbiological stresses (Lee et al. 1976). The obtained data from this study also confirm the abovementioned report. 2.3. Photosynthetic parameters The competition of heavy metals in the absorption of necessary elements such as iron and magnesium is effective in the synthesis of chlorophyll (Burzynski 1987). Molas (2002) reported
Treatment Control 2.5 mM 5 mM 10 mM 25 mM 50 mM Letters denote p , 0.05.
The amount of proline in the shoot 9.93 ^ 0.85e 20.96 ^ 0.97d 29.18 ^ 3.47d 64 ^ 3.91c 90.74 ^ 4.04b 112.37 ^ 2.13a
Natural Product Research
1501
that in Brassica oleracea plant, photosynthesis decreases under nickel stress. Probably, the effect of most of the heavy metals on the centres of reaction which are rich in chlorophyll ‘a’ compared with light-harvesting complexes which are rich in chlorophyll ‘b’ indicates the decrease in the ratio of chlorophyll ‘a’ to chlorophyll ‘b’ (Taiz & Zeiger 2002).
Downloaded by [RMIT University] at 03:51 03 September 2014
2.3.1. Chlorophyll ‘a’, chlorophyll ‘b’ and total chlorophyll The decrease in chlorophyll ‘a’ at the concentration of 50 mM was 2.21 times more than the control, and at the concentration of 2.5 mM, it was 0.12, that is 10.1% which showed a significant difference at the level of 5%. The amount of chlorophyll ‘b’ at concentrations of 50 and 2.5 mM was reduced 2.93 and 0.013 times, respectively, compared with control. Analyses showed that the decrease in the amount of chlorophyll ‘b’ is significant (P , 0.05) at high NiCl22 concentrations than lower concentrations compared with decrease in control. While the amount of total chlorophyll was similar to chlorophyll ‘a’ and ‘b’, the highest concentration caused 86% decrease in total chlorophyll compared with the control (Figure S3). 2.3.2. The ratio of chlorophyll ‘a’ to ‘b’ At higher concentrations, the decrease in the experimental group was significant compared with the lower concentrations. The decrease at the concentration of 50 mM was 1.7 times more than the control sample (Figure S4). 2.3.3. The efficiency of photosystem II (Fv/Fm) The nickel chloride treatment significantly decreased (P , 0.05) the ratio of Fv/Fm (Figure S5). The primary florescence changes according to the structural changes of primary reaction centres in environmental stresses has a potential effect on the decrease in efficiency of photosystem II (Fv/Fm), and the rate of photosynthesis in resistant plants under nickel stress decreases slightly comparing to sensitive plants which have remarkable change in the same environment (Cha-Um & Kirdmanee 2009). By controlling the protein biosynthesis at transcription level, heavy metals prevent the formation of light-harvesting complexes II which have a remarkable role in decreasing the ratio of Fv/Fm. There is a positive relationship between the amount of chlorophyll ‘a’ and ‘b’, the ratio of Fv/Fm and the amount of total chlorophyll, as well as the quantum efficiency of photosystem II. 2.4 The total amount of protein The total amount of protein decreased significantly at higher concentration of Ni (P , 0.001). The amount of decrease in control was 5111.1, and at the highest concentration, it was 1332.9 mg for each g of the wet tissue (73.9% decreases) (Figure S6). Non-biological stresses cause the prevention of production of some proteins, and increase in synthesis of some others (Ericson & Alfinito 1984) which is usually accompanied by the decrease in total protein. The peroxidation of membrane lipids and the destructive effects of different types of active oxygen decrease the total protein (Davies 1987). Under heavy metal stress, the activity of protease increases as well (Palma et al. 2002). 3. Conclusion In conclusion, Ni (as a heavy metal) changes the growing conditions, which affect many physiological parameters of C. roseus plant. Supplementary material Experimental details relating to this article are available online, alongside Figures S1– S6.
1502
M. Arefifard et al.
Notes 1. Like NiCl2. 2. 50 mM.
Downloaded by [RMIT University] at 03:51 03 September 2014
References Abbas SM, Kamel EA. 2004. Rhizobium as a biological agent for preventing heavy metal stress. Asian J Plant Sci. 3:416–424. Alia, Saradhi PP. 1991. Proline accumulation under heavy metal stress. J Plant Physiol. 138:554–558. Azmat R, Haider S, Askari S. 2006. Phyotoxicity of Pb:I. Effect of Pb on germination, growth, morphology and histomorphology of Phaseolus mungo and Lens culinaris. Pak J Biol Sci. 9:979–984. Benaroya RO, Tzin V, Tel-Or E, Zamski E. 2004. Lead accumulation in the aquatic fern Azolla filiculoides. Plant Physiol Biochem. 42:639–645. Burzynski M. 1987. The influence of lead and cadmium absorbtion and distribution of potassium, calcium, magnesium and iron in cucumber seedling. Acta Physiol Plant. 9:229–238. Charest C, Phan CT. 1990. Cold acclimation of wheat (Triticum aestivum) properties of enzymes involved in proline metabolism. Physiol Plant. 80:159–168. Cha-Um S, Kirdmanee C. 2009. Proline accumulation, photosynthetic abilities and growth characters of sugarcane (Saccharum officinarum L.) plantlets in response to iso-osmotic salt and water-deficit stress. Agric Sci China. 8:51–58. Cunningham SD, Ow DW. 1996. Promises and prospects of phytoremediation. Plant Physiol. 110:715–719. Davies KJA. 1987. Protein damage and degradation by oxygen radicals. I. General aspects. J Biol Chem. 262:9895–9901. Eliwa AM. 2000. Some physiological and cytological studied on the effect of ions of heavy metals on Pisum sativum plant [MSc thesis]. Cairo: Ain Shams University. Ericson MC, Alfinito SH. 1984. Proteins produced during salt stress in tobacco cell cultures. Plant Physiol. 74:506–509. Haider H, Kanwal S, Uddin F, Azmat R. 2006. Phytotoxicity of Pb: II. Changes in chlorophyll absorption spectrum due to toxic metal Pb stress on Phaseolus mungo and Lens culinaris. Pak J Biol Sci. 9:2062–2068. Lee KC, Cunningham BA, Poulsen GM, Laing GH, Moore RA. 1976. Effect of cadmium on respiration rate and activities of several enzymes in soybean seedlings. Physiol Plant. 36:4– 6. McGrath SP, Zhao FJ, Lombi E. 2002. Phytoremediation of metals, metalloids and radionuclides. Adv Agron. 75:1–56. Molas J. 2002. Changes of chloroplast ultrastructure and total chlorophyll concentration in cabbage leaves caused by excess of organic Ni(II) complexes. Environ Exp Bot. 47:115–126. Neill SJ, Desikan D, Clarke A, Hancock JT. 2002. Nitric oxide is a novel component of abscisic acid signaling in stomatal guard cells. Plant Physiol. 128:13– 16. Palma JM, Sandalio LM, Javier Corpas F, Romero-Puertas MC, McCarthy I, del Rı´o LA. 2002. Plant proteases protein degradation and oxidative stress: role of peroxisomes. Plant Physiol Biochem. 40:521–530. Scandalios JG. 1993. Oxygen stress and superoxide dismutase. Plant Physiol. 101:7–12. Sivakumar P, Sharmila P, Sharadhi PP. 2000. Proline alleviates salt-stress-induced enhancement in ribulose-oxygenase activity. Biochem Biophys Res Commun. 279:512–515. Taiz L, Zeiger E. 2002. Plant physiology. Sunderland (MA): Sinauer, p. 690. Venekemp JH. 1989. Regulation of cytosolic acidity in plants under condition of drought. Plant Physiol. 76:112–117. Verma DPS. 1999. Osmotic stress tolerance in plants: role of proline and sulfur metabolisms. In: Shinozaki K, Yamaguchi-Shinozaki K, editors. Molecular responses to cold, drought, heat and salt stress in higher plants. Austin (TX): R.G. Landers; p. 153–168. Witte-Claus P, Tiller-Sarah A, Taylor-Mark A, Davies-Howard V. 2002. Addition of nickel to Murashige and Skoog medium in plant tissue culture activates urease and may reduce metabolic stress. Plant Cell Tiss Org. 68:103–110.
Natural Product Research: Formerly Natural Product Letters Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gnpl20
Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus a
a
a
Matin Arefifard , Majid Mahdieh & Mohammadreza Amirjani a
Biological Department, Arak University, Arak, Iran Published online: 28 May 2014.
To cite this article: Matin Arefifard, Majid Mahdieh & Mohammadreza Amirjani (2014) Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus, Natural Product Research: Formerly Natural Product Letters, 28:18, 1499-1502, DOI: 10.1080/14786419.2014.913240 To link to this article: http://dx.doi.org/10.1080/14786419.2014.913240
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/termsand-conditions
Natural Product Research, 2014 Vol. 28, No. 18, 1499–1502, http://dx.doi.org/10.1080/14786419.2014.913240
SHORT COMMUNICATION Study of the effect of nickel heavy metals on some physiological parameters of Catharanthus roseus Matin Arefifard*, Majid Mahdieh and Mohammadreza Amirjani Biological Department, Arak University, Arak, Iran
Downloaded by [RMIT University] at 03:51 03 September 2014
(Received 24 November 2013; final version received 6 April 2014) Plants, in their life cycle, are usually exposed to various kinds of non-biological stresses including heavy metals. One of these heavy metals is nickel which affects many physiological processes of plants. Studies have shown that the changes in planting conditions can affect the qualitative and quantitative features of Catharanthus roseus; therefore, creating stressful conditions (e.g. NiCl2) can be an effective way to investigate the changes. In this research, we investigated the effect of 0, 2.5, 5, 10, 25 and 50 mM concentrations of NiCl2 on the degree of catalase enzyme activity, amount of proline aggregation and photosynthetic parameters on seeds of pink variety of C. roseus. The results indicated that the degree of catalase enzyme activity and the amount of proline aggregation increased in plants which were exposed to NiCl2 treatments, especially in high concentrations, while the total protein decreased. The stress of Ni also affected photosynthetic parameters, and decreased the amount of pigments, as well as the efficiency of photosystem II. Keywords: Catharanthus roseus; nickel heavy metal; catalase; photosynthetic parameters
1. Introduction Plants, in their life cycle, are usually exposed to various kinds of non-biological stresses including heavy metals. The main compounds of mineral pollution are heavy metals (Cunningham & Ow 1996), and their effects depend on many factors such as environmental conditions, pH, organic materials and resistance of variations of plants (Eliwa 2000; Abbas & Kamel 2004). Heavy metals decrease the absorption and transfer of water, because of the downsizing of leaves’ surface (Azmat et al. 2006) which also affects photosynthesis (Haider et al. 2006). The aggregation of proline decreases the harm to the membrane and proteins (Verma 1999). Proline reduces the danger of free radicals by preventing lipid peroxidation. It adjusts the acidity of cytosol and maintains the consistency of NADþ/NADH (Sivakumar et al. 2000). Non-biological stresses alter the production of some proteins which is usually accompanied by the decrease in total protein (Ericson & Alfinito 1984; Alia & Saradhi 1991). The density ratio of metals in plants’ shoot to their root in those which are of high accumulators is more than one less accumulator ones (McGrath et al. 2002). Studies have shown that change in the planting conditions can affect the growth and qualitative and quantitative features of plants including Catharanthus roseus (periwinkle) (2n ¼ 16). The genus Catharanthus belongs to the family Apocynaceae. The growth of the plant is low in the early period of planting, and it has a long period of growth. A small amount of nickel, a heavy element, plays a significant role in nitrogen metabolism and the growth of plants, including C. roseus. Nowadays, nickel has been added to the collection of low consumed elements necessary for plants (Witte-Claus et al. 2002;
*Corresponding author. Email: [email protected] q 2014 Taylor & Francis
1500
M. Arefifard et al.
Benaroya et al. 2004). Among its first poisonous effects is peroxidation of membrane lipids which occurs through activation of lipo-oxygenase enzyme. Then, growth of the plant is controlled by change in the structure of cell membrane. In order to investigate the effect of nickel on C. roseus plant, at concentrations of 0, 2.5, 5, 10, 25 and 50 mM of nickel chloride, an experiment was conducted with factorial design, repeated three times in the Physiology Laboratory of Faculty of Sciences, University of Arak, Iran. The purpose of this study was to investigate the effect of different concentrations of nickel on some phytochemical features such as the amount of chlorophyll, proline, protein and the activity of antioxidant enzymes.
Downloaded by [RMIT University] at 03:51 03 September 2014
2. Results and discussion The statistical design was completely random. The graphs were drawn by using EXCEL, and the analysis of factors was done by using the SPSS software, version 11. The Duncan method was applied in order to compare the means of the obtained data and one-way analysis of variance. 2.1. Proline The amount of proline in the shoot of the plants treated with nickel chloride displayed significant increases compared with control sample (P , 0.001) (Figure S1). The accumulation of proline in plants exposed to heavy metal stress1 decreases the harmful effect on their membrane and proteins (Verma 1999). The increase of proline is because of decrease in analysis was proline decreased, increase in production, decrease in its consumption, and protein hydrolysis (Charest & Phan 1990). Heavy elements cause the decrease in the transfer chain of electron and the accumulation of NADH and Hþ. The production of proline through glutamic acid causes the decrease of accumulated NADH in cells (Venekemp 1989). 2.2. The catalase enzyme activity Nickel chloride did not have a significant effect on catalase activity. The amount of catalase in 50 mM treatment was 1.47 times more than in the control sample (H2O2 used per each mg of total protein per min) (Figure S2). One of the active types of oxygen H2O2 is produced in oxidative reactions in mitochondria and chloroplast (Neill et al. 2002). In the presence of iron iodine, peroxide hydrogen produces free radicals of oxygen (OH*). Peroxide hydrogen turns to water in the cell by catalase enzymes, ascorbate peroxidase and glutathione peroxidase (Scandalios 1993). The activity of the omitting enzymes of reactive oxygen species such as, catalase increases in nonbiological stresses (Lee et al. 1976). The obtained data from this study also confirm the abovementioned report. 2.3. Photosynthetic parameters The competition of heavy metals in the absorption of necessary elements such as iron and magnesium is effective in the synthesis of chlorophyll (Burzynski 1987). Molas (2002) reported
Treatment Control 2.5 mM 5 mM 10 mM 25 mM 50 mM Letters denote p , 0.05.
The amount of proline in the shoot 9.93 ^ 0.85e 20.96 ^ 0.97d 29.18 ^ 3.47d 64 ^ 3.91c 90.74 ^ 4.04b 112.37 ^ 2.13a
Natural Product Research
1501
that in Brassica oleracea plant, photosynthesis decreases under nickel stress. Probably, the effect of most of the heavy metals on the centres of reaction which are rich in chlorophyll ‘a’ compared with light-harvesting complexes which are rich in chlorophyll ‘b’ indicates the decrease in the ratio of chlorophyll ‘a’ to chlorophyll ‘b’ (Taiz & Zeiger 2002).
Downloaded by [RMIT University] at 03:51 03 September 2014
2.3.1. Chlorophyll ‘a’, chlorophyll ‘b’ and total chlorophyll The decrease in chlorophyll ‘a’ at the concentration of 50 mM was 2.21 times more than the control, and at the concentration of 2.5 mM, it was 0.12, that is 10.1% which showed a significant difference at the level of 5%. The amount of chlorophyll ‘b’ at concentrations of 50 and 2.5 mM was reduced 2.93 and 0.013 times, respectively, compared with control. Analyses showed that the decrease in the amount of chlorophyll ‘b’ is significant (P , 0.05) at high NiCl22 concentrations than lower concentrations compared with decrease in control. While the amount of total chlorophyll was similar to chlorophyll ‘a’ and ‘b’, the highest concentration caused 86% decrease in total chlorophyll compared with the control (Figure S3). 2.3.2. The ratio of chlorophyll ‘a’ to ‘b’ At higher concentrations, the decrease in the experimental group was significant compared with the lower concentrations. The decrease at the concentration of 50 mM was 1.7 times more than the control sample (Figure S4). 2.3.3. The efficiency of photosystem II (Fv/Fm) The nickel chloride treatment significantly decreased (P , 0.05) the ratio of Fv/Fm (Figure S5). The primary florescence changes according to the structural changes of primary reaction centres in environmental stresses has a potential effect on the decrease in efficiency of photosystem II (Fv/Fm), and the rate of photosynthesis in resistant plants under nickel stress decreases slightly comparing to sensitive plants which have remarkable change in the same environment (Cha-Um & Kirdmanee 2009). By controlling the protein biosynthesis at transcription level, heavy metals prevent the formation of light-harvesting complexes II which have a remarkable role in decreasing the ratio of Fv/Fm. There is a positive relationship between the amount of chlorophyll ‘a’ and ‘b’, the ratio of Fv/Fm and the amount of total chlorophyll, as well as the quantum efficiency of photosystem II. 2.4 The total amount of protein The total amount of protein decreased significantly at higher concentration of Ni (P , 0.001). The amount of decrease in control was 5111.1, and at the highest concentration, it was 1332.9 mg for each g of the wet tissue (73.9% decreases) (Figure S6). Non-biological stresses cause the prevention of production of some proteins, and increase in synthesis of some others (Ericson & Alfinito 1984) which is usually accompanied by the decrease in total protein. The peroxidation of membrane lipids and the destructive effects of different types of active oxygen decrease the total protein (Davies 1987). Under heavy metal stress, the activity of protease increases as well (Palma et al. 2002). 3. Conclusion In conclusion, Ni (as a heavy metal) changes the growing conditions, which affect many physiological parameters of C. roseus plant. Supplementary material Experimental details relating to this article are available online, alongside Figures S1– S6.
1502
M. Arefifard et al.
Notes 1. Like NiCl2. 2. 50 mM.
Downloaded by [RMIT University] at 03:51 03 September 2014
References Abbas SM, Kamel EA. 2004. Rhizobium as a biological agent for preventing heavy metal stress. Asian J Plant Sci. 3:416–424. Alia, Saradhi PP. 1991. Proline accumulation under heavy metal stress. J Plant Physiol. 138:554–558. Azmat R, Haider S, Askari S. 2006. Phyotoxicity of Pb:I. Effect of Pb on germination, growth, morphology and histomorphology of Phaseolus mungo and Lens culinaris. Pak J Biol Sci. 9:979–984. Benaroya RO, Tzin V, Tel-Or E, Zamski E. 2004. Lead accumulation in the aquatic fern Azolla filiculoides. Plant Physiol Biochem. 42:639–645. Burzynski M. 1987. The influence of lead and cadmium absorbtion and distribution of potassium, calcium, magnesium and iron in cucumber seedling. Acta Physiol Plant. 9:229–238. Charest C, Phan CT. 1990. Cold acclimation of wheat (Triticum aestivum) properties of enzymes involved in proline metabolism. Physiol Plant. 80:159–168. Cha-Um S, Kirdmanee C. 2009. Proline accumulation, photosynthetic abilities and growth characters of sugarcane (Saccharum officinarum L.) plantlets in response to iso-osmotic salt and water-deficit stress. Agric Sci China. 8:51–58. Cunningham SD, Ow DW. 1996. Promises and prospects of phytoremediation. Plant Physiol. 110:715–719. Davies KJA. 1987. Protein damage and degradation by oxygen radicals. I. General aspects. J Biol Chem. 262:9895–9901. Eliwa AM. 2000. Some physiological and cytological studied on the effect of ions of heavy metals on Pisum sativum plant [MSc thesis]. Cairo: Ain Shams University. Ericson MC, Alfinito SH. 1984. Proteins produced during salt stress in tobacco cell cultures. Plant Physiol. 74:506–509. Haider H, Kanwal S, Uddin F, Azmat R. 2006. Phytotoxicity of Pb: II. Changes in chlorophyll absorption spectrum due to toxic metal Pb stress on Phaseolus mungo and Lens culinaris. Pak J Biol Sci. 9:2062–2068. Lee KC, Cunningham BA, Poulsen GM, Laing GH, Moore RA. 1976. Effect of cadmium on respiration rate and activities of several enzymes in soybean seedlings. Physiol Plant. 36:4– 6. McGrath SP, Zhao FJ, Lombi E. 2002. Phytoremediation of metals, metalloids and radionuclides. Adv Agron. 75:1–56. Molas J. 2002. Changes of chloroplast ultrastructure and total chlorophyll concentration in cabbage leaves caused by excess of organic Ni(II) complexes. Environ Exp Bot. 47:115–126. Neill SJ, Desikan D, Clarke A, Hancock JT. 2002. Nitric oxide is a novel component of abscisic acid signaling in stomatal guard cells. Plant Physiol. 128:13– 16. Palma JM, Sandalio LM, Javier Corpas F, Romero-Puertas MC, McCarthy I, del Rı´o LA. 2002. Plant proteases protein degradation and oxidative stress: role of peroxisomes. Plant Physiol Biochem. 40:521–530. Scandalios JG. 1993. Oxygen stress and superoxide dismutase. Plant Physiol. 101:7–12. Sivakumar P, Sharmila P, Sharadhi PP. 2000. Proline alleviates salt-stress-induced enhancement in ribulose-oxygenase activity. Biochem Biophys Res Commun. 279:512–515. Taiz L, Zeiger E. 2002. Plant physiology. Sunderland (MA): Sinauer, p. 690. Venekemp JH. 1989. Regulation of cytosolic acidity in plants under condition of drought. Plant Physiol. 76:112–117. Verma DPS. 1999. Osmotic stress tolerance in plants: role of proline and sulfur metabolisms. In: Shinozaki K, Yamaguchi-Shinozaki K, editors. Molecular responses to cold, drought, heat and salt stress in higher plants. Austin (TX): R.G. Landers; p. 153–168. Witte-Claus P, Tiller-Sarah A, Taylor-Mark A, Davies-Howard V. 2002. Addition of nickel to Murashige and Skoog medium in plant tissue culture activates urease and may reduce metabolic stress. Plant Cell Tiss Org. 68:103–110.
