Effect of mercury on seedling growth, nodulation and ultrastructural deformation of Vigna radiata (L) Wilczek

• Published in: Environmental monitoring and assessment Vol. 187; no. 5; p. 241
• Main Authors: Mondal, Naba Kumar, Das, Chittaranjan, Datta, Jayanta Kumar
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.05.2015; Springer Nature B.V
• Subjects: Atmospheric Protection/Air Quality Control/Air Pollution; Beans; Chemical properties; Chlorophyll; Chlorophyll - analogs & derivatives; Chlorophyll - metabolism; Earth and Environmental Science; Ecology; Ecotoxicology; Environment; Environmental Management; Environmental Monitoring; Fabaceae - drug effects; Fabaceae - growth & development; Fabaceae - ultrastructure; Hazardous materials; Heavy metals; Leaf area; Leaves; Legumes; Malondialdehyde; Mercury; Mercury - toxicity; Monitoring/Environmental Analysis; Morphology; Nitrogen fixation; Nodulation; Nodules; Physiology; Plant Leaves; Plant Root Nodulation - drug effects; Plant Roots - drug effects; Plant Roots - ultrastructure; Salts; Scanning electron microscopy; Seedlings; Seedlings - drug effects; Seedlings - growth & development; Seedlings - ultrastructure; Seeds; Shoots; Sodium Chloride; Soil; Soil Pollutants - toxicity; Toxicity; Vigna radiata; Leg haemoglobin; Chlorophyll; SEM; Hg solution; Mungbean; Root nodule
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-015-4484-8

Heavy metals are major environmental pollutant when they present in high concentration in soil and have toxic effects on growth, nodulation and nitrogen fixation of legumes and development of plants. Mercury stress triggers disturbances in cellular structure, and metabolismn is poorly understood. The response of seedling growth and nodulation of Vigna radiata (L) Wilczek to different concentrations (0.1, 0.5, 1.0 and 1.5 ppm) of mercury (Hg) salt solutions were studied. Morphological parameters like root and shoot length, dry weight, nodule number, total leaf area and biochemical constituents (chlorophyll, malondialdehyde and leghaemoglobin) of bean plants were recorded at an interval of 30 days. The successive growth deformaties in seedlings and nodules were recorded at lower concentration (0.1 ppm), but marginal (0.5 ppm) and higher (1.0 ppm) level of Hg salt solution showed significant suppression. The maximum level of Hg concentration (1.5 ppm) shows high level of tolerance index without any nodule. The control treatment shows maximum level of leghaemoglobin (0.219 mM) and all other morpho-physiological and bio-chemical properties of roots and shoots excepting tolerance index (0.00) and chlorophyll ‘a’ (7.52 mg g −1 FW). Mercury accumulation pattern follows the sequences: leaf > nodule > root ≈ shoot at lower level of Hg (0.1 and 0.5 ppm). However, higher level of Hg (1.0 and 1.5 ppm) showed shoot > root > leaf > nodule. The scanning electron microscopy (SEM) study of root also highlights the deleterious effect of Hg salt at higher concentration.