Renu Bhardwaj - Academia.edu (original) (raw)

Papers by Renu Bhardwaj

Brassinosteroids: A Class of Plant Hormone, 2010

Steroids are an imperative group of hormones which play a key role in the transmission of signals... more Steroids are an imperative group of hormones which play a key role in the transmission of signals that mediate growth and physiological responses in most pluricellular organisms. Brassinosteroids (BRs), a class of plant-specific steroid hormones, control many of the developmental and physiological processes like their animal counterparts, including regulation of gene expression, cell division and expansion, differentiation, programmed cell death,

The present work has been undertaken to study the role of different concentrations of 24-epibrass... more The present work has been undertaken to study the role of different concentrations of 24-epibrassinolide (24-EBL) (10 -10 , 10 -8 and 10 -6 M) on growth, antioxidant enzyme [catalase (CAT), ascorbate peroxidase (APOX), superoxide dismutase (SOD)] activities and total protein content in 10-days-old seedlings of Brassica juncea L. exposed to heat stress for 5 h daily for three consecutive days. Heat treatment lowered total protein content of B. juncea seedlings. The seedlings treated with different concentrations of 24-EBL showed better growth and enhanced protein content than the control. Similarly, the activities of SOD, CAT, APOX, PPO, and auxinases were enhanced by the application of different concentrations of 24-epiBL. APOX activity was enhanced maximum with 10 -10 M 24-epiBL while 10 -8 M was most effective for maximum enhancement in the activity of CAT and SOD.

Second stage juveniles (J2) of Meloidogyne incognita were exposed for 48 hours in vitro, to six c... more Second stage juveniles (J2) of Meloidogyne incognita were exposed for 48 hours in vitro, to six concentrations (ranging from 10-5 M to 10-10 M) of two of the most potent brassinosteroids, 28-homobrassinolide and 24-epibrassinolide. A higher mortality was observed in some of the concentrations of 28-homobrassinolide and 24-epibrassinolide. The treated juveniles were allowed to develop on tomato seedlings grown in pots filled with sterilized soil. The juveniles treated with brassinosteroids resulted in more galls and egg masses when examined after 45 days. The stimulating effect of 28-homobrassinolide and 24-epibrassinolide on the development of this root-knot nematode is indicated in these preliminary observations.

Phytoremediation is an emerging technique for the safe, clean up of contaminated habitats. A numb... more Phytoremediation is an emerging technique for the safe, clean up of contaminated habitats. A number of plants have the capacity of accumulating large amounts of pollutants and degrade them to less toxic form. Water hyacinth is an aquatic weed, which have been studied for its potential of pyhtoremediation. In the present work, an attempt has been made to study the uptake of mercury and its effects on activities of peroxidase and ascorbic acid oxidase. The uptake of different concentrations (10, 20,40,60,80 &100 ppb) of mercuric chloride was studied in roots, petioles and leaf laminae. Maximum uptake of metal was observed in roots and correspondingly the enzyme activities were also found to be enhanced at 10 and 100 ppb concentrations of the metal. The bioconcentration factor (BCF) was also noted and found maximum in the roots of the plants.

An effective management of lakes requires their description and classification as per the accepte... more An effective management of lakes requires their description and classification as per the accepted scientific norms. Lakes may be characterized and classified on the basis of depth, surface area, shoreline, littoral area, shape, trophic status, chlorophyll content, Secchi disc transparency, phosphorus content, mixis, water hardness, salinity and many other such characteristics. Osgood Index, Shoreline Development Factor and Trophic State Indices are the important indices for lake characterization and classification. In the present paper we propose Lake Interface Factors at air-water and soil-water interfaces, which would take into account area characteristics of the lake water at the interface of air and soil in relation to lake volume.

The influence of isolated brassinosteroids (Iso BRs) was investigated at morphogenetic as well as... more The influence of isolated brassinosteroids (Iso BRs) was investigated at morphogenetic as well as biochemical level in Meloidogyne incognita. The egg masses J2 of M. incognita were exposed, in vitro to six concentrations (ranging from 10−10 to 10−5 M) of Iso BRs for 7 days and 48 hrs, respectively. Observations recorded revealed higher percentage of hatching in treated egg masses as compared to control whereas there was no effect on juvenile vigour. Hatched juveniles from treated egg masses and the treated juveniles were further allowed to develop on plants for 45 days. BRs treated juveniles resulted into more gall number of larger size of galls as compared to untreated ones. For biochemcial evaluation, the activity of four enzymes viz. catalase, esterases, superoxide dismutase (SOD) and glutathione S-transferases(GST) were assessed in the J2 of M. incognita after the treatment of egg masses with BRs. The activity of catalase and esterases increased with brassinosteroids treatments ...

The effects of 28-homobrassinolide (28-homoBL) on growth, lipid peroxidation and antioxidative en... more The effects of 28-homobrassinolide (28-homoBL) on growth, lipid peroxidation and antioxidative enzyme activities in the Zea mays L. (var. Partap-1) seedlings exposed to zinc (Zn) metal were studied. The surface sterilized seeds of Zea mays were given treatments of different concentrations of Zn metal (0.5, 1.0, 1.5 and 2.0 mM) alone or in combination with 28-homoBL (10-4, 10-6 and 10-8 mM) for seven days. The activities of antioxidative enzymes (superoxide dismutase (EC 1.15.1.1) catalase (EC 1.11.1.6), ascorbate peroxidase (EC 1.11.1.11), guaiacol peroxidase (EC 1.11.1.7) and glutathione reductase (EC 1.6.4.2)), protein and malondialdehyde (MDA) content were analyzed in seven days old seedlings. It was observed that 28-homoBL treatments stimulated the activities of antioxidative enzymes and the level of MDA content was decreased, thus indicating the stress-ameliorative effects of 28-homoBL.

The study was undertaken to assess the suitability of Brassica juncea L. cv. 'PBR-91' for phytore... more The study was undertaken to assess the suitability of Brassica juncea L. cv. 'PBR-91' for phytoremediation of multi-heavy element contaminated soils. Growth and heavy metal uptake potential of B. juncea seedlings were determined in binary combinations of Cr(VI) with Mn, Ni, Co, Cu and Zn at concentrations varying up to 100 mg/l. Multiple regression interaction models revealed that all the metals, whether applied singly or in combinations, inhibited the growth of seedlings. In a single metal treatment, Cr(VI) (100 mg/l) decreased the germination percentage, root length, shoot length and dry weight to the maximum extent. The interactive effects of binary combinations of Cr(VI) with other metals were generally mutually antagonistic and decreased the toxicity of each other on seedling growth. The maximum uptake was recorded for 100 mg/l each of Zn and Mn, being 0.531 and 0.445 mg/g dw, respectively. The lowest heavy metal uptake was observed for Ni (0.135 mg/g dw) at a concentration of 100 mg/l. Multiple regression interaction models also revealed that the interaction between Cr and the other metals in binary combinations decreased the uptake of Cr by seedlings. This study established that Zn and Mn significantly reduce the deleterious effects of Cr(VI) on seedling growth in B. juncea. _____________________________________________________________________________________________________________ Keywords: antagonism, binary interactions, Co, Cu, Mn, Ni, Zn Abbreviations: ANOVA, analysis of variance ® Abou-Shanab R, Ghanem N, Ghanem K, Al-Kolaibe A (2007) Phytoremediation potential of crop and wild plants for multimetal contaminated soils. An Y, Kim Y, Kwon T, Jeong S (2004) Combined toxicity of Cu, Cd and Pb upon Cucumis sativus growth and bioaccumulation. Science of the Total Environment 326, 85-93 Ansari KH, Ahmed A, Umar S, Iqbal M (2009) Mercury induced changes in growth variables and antioxidative enzyme activities in Indian mustard. Journal of Plant Interactions 4, 131-136 Aravind P, Prasad MNV (2005) Cd-Zn interactions in a hydroponic system using C. demersum L.: Adaptive ecophysiology, biochemistry and molecular toxicology. Brazilian Journal of Plant Physiology 17, 3-20 Bailey NTJ (1995) Statistical Methods in Biology, Cambridge University Press, Cambridge, 255 pp Barceló J, Poschenriender C, Ruano A, Gunse B (1985) Leaf water potential in Cr(VI) treated bean plants (Phaseolus vulgaris L). Plant Physiology 77 (Suppl.), 163-164 Bassi M, Corradi MG, Realini M (1990) Effects of chromium (VI) on two fresh water plants, Lemna minor and Pistia stratiotes. 1. Morphological observations. Cytobios 62, 27-38 Baszynski M, Buczek JT, Wajda L, Krol M, Wolinska D, Krupa Z, Tukendorf A (1980) Photosynthetic activities of cadmium-treated tomato plants. Physiologia Plantarum 48, 365-370 Biddappa CC, Bopaiah MG (1989) Effect of heavy metals on the distribution of P, K, Ca, Mg and micronutrients in the cellular constituents of coconut leaf. R (2001) Interactions of chromium with microorganisms and plants. FEMS Microbiology Review 25, 335-347 Chaoui A, Ghorbal MH, El Ferjani (1997) Effects of Cd-Zn interactions on hydroponically grown bean (Phaseolus vulgaris L.). Plant Science 126, 21-28 Chen NC, Kanazawa S, Horiguchi T, Chen NC (2001) Effect of chromium on some enzyme activities in the wheat rhizosphere. Soil Microorganisms 55, 3-10 Chen S, Zhou Q, Sun T, Li P (2003) Rapid ecotoxicolgical assessment of heavy metal combined polluted soil using canonical analysis. Journal of Environmental Sciences 15, 854-858 Coughtrey PJ, Martin MH (1978) Tolerance of Holcus lanatus to Pb, Zn and Cd in factorial combinations. New Phytologist 81, 147-154 Cunningham SD, Ow DW (1996) Promises and prospects of phytoremediation. Plant Physiology 110, 715-719 Davies FT, Puryear JD, Newton RJ, Grossi JAS (2001) Mycorrhizal fungi enhance accumulation and tolerance of chromium in sunflower (Helianthus annuus). Journal of Plant Physiology 158, 777-786 Dickinson NM, Baker AJM, Doronila A, Laidlaw S, Reeves RD (2009) Phytoremediation of inorganics: Realism and synergies. International Journal of Phytoremediation 11, 97-114 Diwan H, Ahmed A, Iqbal M (2008) Genotypic variation in the phytoremediation potential of Indian mustard for chromium. Environmental Management 41, 734-736 Dowling DN, Doty SL (2009) Improving phytoremediation through biotechnology.

The present study attempts to understand the uptake of heavy metals and stress tolerance in Brass... more The present study attempts to understand the uptake of heavy metals and stress tolerance in Brassica juncea L. seedlings under the effect of Zn in binary combinations with Cr, Ni, Co and Cu through the production of antioxidative enzymes -superoxide dismutase (SOD), guaiacol peroxidase (GPX), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR). It was observed that the order of uptake of heavy metals by the seedling in single metal solutions was Zn > Cu > Co > Cr > Ni. Zn in binary combination with other heavy metals, mutually decreased the uptake of each other, the maximum decrease being 66.1% in the uptake of Cr in (Cr100+Zn100) binary solution. All the metals, whether applied singly or in combinations, significantly increased the activities of antioxidative enzymes, except for CAT. Zn was the most effective metal in increasing the activities of antioxidative enzymes. At 100 mg l -1 , it increased the activities of GR, GPX and APX by 101%, 64%, and 42% respectively, whereas maximum SOD activity (16 mM UA mg -1 protein) was induced by 100 mg l -1 Cr. Of all the binary combinations, Zn+Co and Zn+Ni were most effective in increasing the activities of GPX and GR, respectively, whereas Zn+Cu and Zn+Cr increased the activities of APX and SOD, respectively. Binary interaction models revealed that Cr, Ni, Co and Cu act antagonistic to Zn to increase the activity of GR, whereas for GPX, APX and SOD, these metals in binary combinations with Zn, were mutually antagonistic, thereby causing a negative interactive effect. Cr, Co and Cu were mutually antagonistic to Zn for catalase activity, whereas interaction between Ni and Zn was synergistic for this enzyme.

Brassinosteroids: A Class of Plant Hormone, 2010

Steroids are an imperative group of hormones which play a key role in the transmission of signals... more Steroids are an imperative group of hormones which play a key role in the transmission of signals that mediate growth and physiological responses in most pluricellular organisms. Brassinosteroids (BRs), a class of plant-specific steroid hormones, control many of the developmental and physiological processes like their animal counterparts, including regulation of gene expression, cell division and expansion, differentiation, programmed cell death,

The present work has been undertaken to study the role of different concentrations of 24-epibrass... more The present work has been undertaken to study the role of different concentrations of 24-epibrassinolide (24-EBL) (10 -10 , 10 -8 and 10 -6 M) on growth, antioxidant enzyme [catalase (CAT), ascorbate peroxidase (APOX), superoxide dismutase (SOD)] activities and total protein content in 10-days-old seedlings of Brassica juncea L. exposed to heat stress for 5 h daily for three consecutive days. Heat treatment lowered total protein content of B. juncea seedlings. The seedlings treated with different concentrations of 24-EBL showed better growth and enhanced protein content than the control. Similarly, the activities of SOD, CAT, APOX, PPO, and auxinases were enhanced by the application of different concentrations of 24-epiBL. APOX activity was enhanced maximum with 10 -10 M 24-epiBL while 10 -8 M was most effective for maximum enhancement in the activity of CAT and SOD.

Second stage juveniles (J2) of Meloidogyne incognita were exposed for 48 hours in vitro, to six c... more Second stage juveniles (J2) of Meloidogyne incognita were exposed for 48 hours in vitro, to six concentrations (ranging from 10-5 M to 10-10 M) of two of the most potent brassinosteroids, 28-homobrassinolide and 24-epibrassinolide. A higher mortality was observed in some of the concentrations of 28-homobrassinolide and 24-epibrassinolide. The treated juveniles were allowed to develop on tomato seedlings grown in pots filled with sterilized soil. The juveniles treated with brassinosteroids resulted in more galls and egg masses when examined after 45 days. The stimulating effect of 28-homobrassinolide and 24-epibrassinolide on the development of this root-knot nematode is indicated in these preliminary observations.

Phytoremediation is an emerging technique for the safe, clean up of contaminated habitats. A numb... more Phytoremediation is an emerging technique for the safe, clean up of contaminated habitats. A number of plants have the capacity of accumulating large amounts of pollutants and degrade them to less toxic form. Water hyacinth is an aquatic weed, which have been studied for its potential of pyhtoremediation. In the present work, an attempt has been made to study the uptake of mercury and its effects on activities of peroxidase and ascorbic acid oxidase. The uptake of different concentrations (10, 20,40,60,80 &100 ppb) of mercuric chloride was studied in roots, petioles and leaf laminae. Maximum uptake of metal was observed in roots and correspondingly the enzyme activities were also found to be enhanced at 10 and 100 ppb concentrations of the metal. The bioconcentration factor (BCF) was also noted and found maximum in the roots of the plants.

An effective management of lakes requires their description and classification as per the accepte... more An effective management of lakes requires their description and classification as per the accepted scientific norms. Lakes may be characterized and classified on the basis of depth, surface area, shoreline, littoral area, shape, trophic status, chlorophyll content, Secchi disc transparency, phosphorus content, mixis, water hardness, salinity and many other such characteristics. Osgood Index, Shoreline Development Factor and Trophic State Indices are the important indices for lake characterization and classification. In the present paper we propose Lake Interface Factors at air-water and soil-water interfaces, which would take into account area characteristics of the lake water at the interface of air and soil in relation to lake volume.

The influence of isolated brassinosteroids (Iso BRs) was investigated at morphogenetic as well as... more The influence of isolated brassinosteroids (Iso BRs) was investigated at morphogenetic as well as biochemical level in Meloidogyne incognita. The egg masses J2 of M. incognita were exposed, in vitro to six concentrations (ranging from 10−10 to 10−5 M) of Iso BRs for 7 days and 48 hrs, respectively. Observations recorded revealed higher percentage of hatching in treated egg masses as compared to control whereas there was no effect on juvenile vigour. Hatched juveniles from treated egg masses and the treated juveniles were further allowed to develop on plants for 45 days. BRs treated juveniles resulted into more gall number of larger size of galls as compared to untreated ones. For biochemcial evaluation, the activity of four enzymes viz. catalase, esterases, superoxide dismutase (SOD) and glutathione S-transferases(GST) were assessed in the J2 of M. incognita after the treatment of egg masses with BRs. The activity of catalase and esterases increased with brassinosteroids treatments ...

The effects of 28-homobrassinolide (28-homoBL) on growth, lipid peroxidation and antioxidative en... more The effects of 28-homobrassinolide (28-homoBL) on growth, lipid peroxidation and antioxidative enzyme activities in the Zea mays L. (var. Partap-1) seedlings exposed to zinc (Zn) metal were studied. The surface sterilized seeds of Zea mays were given treatments of different concentrations of Zn metal (0.5, 1.0, 1.5 and 2.0 mM) alone or in combination with 28-homoBL (10-4, 10-6 and 10-8 mM) for seven days. The activities of antioxidative enzymes (superoxide dismutase (EC 1.15.1.1) catalase (EC 1.11.1.6), ascorbate peroxidase (EC 1.11.1.11), guaiacol peroxidase (EC 1.11.1.7) and glutathione reductase (EC 1.6.4.2)), protein and malondialdehyde (MDA) content were analyzed in seven days old seedlings. It was observed that 28-homoBL treatments stimulated the activities of antioxidative enzymes and the level of MDA content was decreased, thus indicating the stress-ameliorative effects of 28-homoBL.

The study was undertaken to assess the suitability of Brassica juncea L. cv. 'PBR-91' for phytore... more The study was undertaken to assess the suitability of Brassica juncea L. cv. 'PBR-91' for phytoremediation of multi-heavy element contaminated soils. Growth and heavy metal uptake potential of B. juncea seedlings were determined in binary combinations of Cr(VI) with Mn, Ni, Co, Cu and Zn at concentrations varying up to 100 mg/l. Multiple regression interaction models revealed that all the metals, whether applied singly or in combinations, inhibited the growth of seedlings. In a single metal treatment, Cr(VI) (100 mg/l) decreased the germination percentage, root length, shoot length and dry weight to the maximum extent. The interactive effects of binary combinations of Cr(VI) with other metals were generally mutually antagonistic and decreased the toxicity of each other on seedling growth. The maximum uptake was recorded for 100 mg/l each of Zn and Mn, being 0.531 and 0.445 mg/g dw, respectively. The lowest heavy metal uptake was observed for Ni (0.135 mg/g dw) at a concentration of 100 mg/l. Multiple regression interaction models also revealed that the interaction between Cr and the other metals in binary combinations decreased the uptake of Cr by seedlings. This study established that Zn and Mn significantly reduce the deleterious effects of Cr(VI) on seedling growth in B. juncea. _____________________________________________________________________________________________________________ Keywords: antagonism, binary interactions, Co, Cu, Mn, Ni, Zn Abbreviations: ANOVA, analysis of variance ® Abou-Shanab R, Ghanem N, Ghanem K, Al-Kolaibe A (2007) Phytoremediation potential of crop and wild plants for multimetal contaminated soils. An Y, Kim Y, Kwon T, Jeong S (2004) Combined toxicity of Cu, Cd and Pb upon Cucumis sativus growth and bioaccumulation. Science of the Total Environment 326, 85-93 Ansari KH, Ahmed A, Umar S, Iqbal M (2009) Mercury induced changes in growth variables and antioxidative enzyme activities in Indian mustard. Journal of Plant Interactions 4, 131-136 Aravind P, Prasad MNV (2005) Cd-Zn interactions in a hydroponic system using C. demersum L.: Adaptive ecophysiology, biochemistry and molecular toxicology. Brazilian Journal of Plant Physiology 17, 3-20 Bailey NTJ (1995) Statistical Methods in Biology, Cambridge University Press, Cambridge, 255 pp Barceló J, Poschenriender C, Ruano A, Gunse B (1985) Leaf water potential in Cr(VI) treated bean plants (Phaseolus vulgaris L). Plant Physiology 77 (Suppl.), 163-164 Bassi M, Corradi MG, Realini M (1990) Effects of chromium (VI) on two fresh water plants, Lemna minor and Pistia stratiotes. 1. Morphological observations. Cytobios 62, 27-38 Baszynski M, Buczek JT, Wajda L, Krol M, Wolinska D, Krupa Z, Tukendorf A (1980) Photosynthetic activities of cadmium-treated tomato plants. Physiologia Plantarum 48, 365-370 Biddappa CC, Bopaiah MG (1989) Effect of heavy metals on the distribution of P, K, Ca, Mg and micronutrients in the cellular constituents of coconut leaf. R (2001) Interactions of chromium with microorganisms and plants. FEMS Microbiology Review 25, 335-347 Chaoui A, Ghorbal MH, El Ferjani (1997) Effects of Cd-Zn interactions on hydroponically grown bean (Phaseolus vulgaris L.). Plant Science 126, 21-28 Chen NC, Kanazawa S, Horiguchi T, Chen NC (2001) Effect of chromium on some enzyme activities in the wheat rhizosphere. Soil Microorganisms 55, 3-10 Chen S, Zhou Q, Sun T, Li P (2003) Rapid ecotoxicolgical assessment of heavy metal combined polluted soil using canonical analysis. Journal of Environmental Sciences 15, 854-858 Coughtrey PJ, Martin MH (1978) Tolerance of Holcus lanatus to Pb, Zn and Cd in factorial combinations. New Phytologist 81, 147-154 Cunningham SD, Ow DW (1996) Promises and prospects of phytoremediation. Plant Physiology 110, 715-719 Davies FT, Puryear JD, Newton RJ, Grossi JAS (2001) Mycorrhizal fungi enhance accumulation and tolerance of chromium in sunflower (Helianthus annuus). Journal of Plant Physiology 158, 777-786 Dickinson NM, Baker AJM, Doronila A, Laidlaw S, Reeves RD (2009) Phytoremediation of inorganics: Realism and synergies. International Journal of Phytoremediation 11, 97-114 Diwan H, Ahmed A, Iqbal M (2008) Genotypic variation in the phytoremediation potential of Indian mustard for chromium. Environmental Management 41, 734-736 Dowling DN, Doty SL (2009) Improving phytoremediation through biotechnology.

The present study attempts to understand the uptake of heavy metals and stress tolerance in Brass... more The present study attempts to understand the uptake of heavy metals and stress tolerance in Brassica juncea L. seedlings under the effect of Zn in binary combinations with Cr, Ni, Co and Cu through the production of antioxidative enzymes -superoxide dismutase (SOD), guaiacol peroxidase (GPX), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR). It was observed that the order of uptake of heavy metals by the seedling in single metal solutions was Zn > Cu > Co > Cr > Ni. Zn in binary combination with other heavy metals, mutually decreased the uptake of each other, the maximum decrease being 66.1% in the uptake of Cr in (Cr100+Zn100) binary solution. All the metals, whether applied singly or in combinations, significantly increased the activities of antioxidative enzymes, except for CAT. Zn was the most effective metal in increasing the activities of antioxidative enzymes. At 100 mg l -1 , it increased the activities of GR, GPX and APX by 101%, 64%, and 42% respectively, whereas maximum SOD activity (16 mM UA mg -1 protein) was induced by 100 mg l -1 Cr. Of all the binary combinations, Zn+Co and Zn+Ni were most effective in increasing the activities of GPX and GR, respectively, whereas Zn+Cu and Zn+Cr increased the activities of APX and SOD, respectively. Binary interaction models revealed that Cr, Ni, Co and Cu act antagonistic to Zn to increase the activity of GR, whereas for GPX, APX and SOD, these metals in binary combinations with Zn, were mutually antagonistic, thereby causing a negative interactive effect. Cr, Co and Cu were mutually antagonistic to Zn for catalase activity, whereas interaction between Ni and Zn was synergistic for this enzyme.