%0 Journal Article
%T Chromium (VI) Induced Biochemical Changes and Gum Content in Cluster Bean (Cyamopsis tetragonoloba L.) at Different Developmental Stages
%A Punesh Sangwan
%A Vinod Kumar
%A R. S. Khatri
%A U. N. Joshi
%J Journal of Botany
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/578627
%X Chromium (Cr) contamination by various industries and other activities is known to inhibit plants growth and development. The present study was conducted using pot experiments in a net house to determine the effect of Cr (VI) on biochemical parameters such as photosynthetic pigments, reducing sugars, and important minerals at different stages of growth in leaves, stem, and roots of clusterbean, a multipurpose fodder crop including a source of guar gum. Guar gum content was estimated in seeds at maturity. All biochemical contents showed a great variation with respect to increase in Cr concentration at different stages of growth. The levels of K, Fe, and Zn decreased, while Cr and Na content increased with increase in Cr concentration. Cr induced toxicity in clusterbean appears at 0.5£¿mg Cr (VI) Kg£¿1 soil with maximum inhibitory effect at 2£¿mg Cr (VI) Kg£¿1 soil, where impaired sugar supply resulted in decreased guar gum synthesis and altered micronutrient content. The study reveals the possible role of these biochemical parameters in decreasing plant growth and development under heavy metal stress. 1. Introduction The molecular and physiological basis of crop plant interactions with the environment has attracted considerable interest in recent years. Being sessile organisms, plants are constantly exposed during their life cycle to adverse environmental conditions that negatively affect growth, development, or productivity. The presence of toxic heavy metals from various industrial activities causes damage to plants by altering major plant physiological and metabolic processes [1, 2]. These metals enter into the soil through different ways including use of fertilizers and pesticides [3]. Crop plants growing in high levels of chromium (Cr) showed a series of physiological disorders, such as reduction of chlorophyll content, sugars, and protein content and decreased photosynthesis leading to lower yield and plant death [4, 5]. Among variable forms of Cr, highly reactive Cr (VI) was found to be toxic to plants in high concentration remaining stable for several months in the soil without changing its oxidation state [6]. It was mainly released in the soil from leather tanning, textile, carpet, electroplating industries, mining industry, and metal cleaning [7, 8]. The interactions between Cr and other nutrients led to changes in nutrient content and physiological disorders with reduction of plant growth and yield. The uptake of several nutrients (potassium (K), magnesium (Mg), phosphorus (P), manganese (Mn), and iron (Fe)) by plants is hindered by high Cr
%U http://www.hindawi.com/journals/jb/2013/578627/