CU AND CD TOLERANCE OF BARLEY AND WHITE MUSTARD: POTENTIAL INDICATORS OF WATER CONTAMINATION WITH THESE HEAVY METALS PUBLISHEDSonja GVOZDENAC, Dušanka INĐIĆ, Slavica VUKOVIĆ, Vojislava BURSIĆ None
Environmental pollution with heavy metals is one of the major current problems, because theiruncontrolled release has already led to accumulation in water and sediment. Some heavy metals areessential for plant development like Cu while others like Cd are not. However, both can cause phyto-toxiceffects when present at high levels in the environment. Maximal allowable amounts (MAC) according tovalid Directives are: in surface and underground waters of II and III class 5 μg/l Cu, 0.45-0.6 μg/l Cdand in irrigation water 100 μg/l Cu, 10 μg/l Cd. However, the content of Cu and Cd in watercoursesoften exceeds the abovementioned limits. Therefore, its detection in water is significant for water riskassessment, and the roll of plants as bioindicators is gaining in importance. The aim of this study was toevaluate the tolerance of barley (Horedum vulgare L.) and white mustard (Sinapis alba L.) to differentlevels of Cu and Cd in water, as potential bioindicators of water pollution with these heavy metals. Astandard filter paper method (ISTA Regulations book, 2011) was used. The toxic effects of Cu (0.025-100μg/l) and Cd (0.01- 200μg/l) were assessed on physiological (germination) and morphological (root andshoot length and fresh and dry weights) traits of test species. The results were processed with Duncan`smultiple range test. Plant responses to metals were species and concentration dependant. Cu and Cd didnot affect germination of barley seeds, regardless on concentration. However, Cu inhibited seedlings rootgrowth and fresh weight at 0.025 μg/l, dry weight, shoot growth and fresh shoot weight at 2 μg/l. Cdinhibited only root and shoot growth of barley seedlings at 100 μg/l. Germination of white mustard seedswas significantly reduced in treatments with 5 μg/l Cu and 1 μg/l Cd. Root growth was inhibited at 2, 50and 100 μg/l Cu, while the presence of 1 μg/l Cu in water significantly reduced fresh root weight. Cd at200 μg/l inhibited root length of white mustard seedlings, while shoot length was stimulated at >10 μg/lCd. Results indicate at barley and white mustard sensitivity towards Cu, when present in water inamounts lower than MACs. However, Cd in amounts lower than MACs had no effect on most of theobserved traits of tested plants.
Cu, Cd, barely, white mustard, metal tolerance, bioindicators