Avena ludoviciana, Cadmium, Cauliflower, Copper, Lead, Parthenium, Wheat
The weed species emerged in wheat and cauliflower were screened for heavy metal accumulation ability under sewage water contaminated sites in Jabalpur and adjoining areas. It was observed that nearly 2-10 times higher accumulation of DTPA extractable heavy metals, viz. 0.42-6.30 µg/g cadmium, 2.43-24.1 µg/g lead, 3.06-89.43 µg/g copper, 88.9-226 µg/g manganese and 30-200 µg/g iron were recorded in sewage water soils than the tube well irrigated soils containing 0.69 µg/g Cd, 2.85 µg/g Pb, 62.8 µg/g Mn, 7.36 µg/g Cu, and 37.7 µg/g Fe. Relatively crops accumulated metals to lower extent than the weed species. Among weed species, Avena ludoviciana removed higher 69.6-122.3 µg/g manganese and 48.9-104 µg/g copper, Parthenium hysterophorus extracted 1065-2507 µg/g iron whereas Sonchus arvensis extracted 3.07 µg/g cadmium which were higher than the metal hyperaccumulating Brassica juncea (43.5 µg/g Mn, 19.0 µg/g Cu, 1352 µg/g Fe, 1.40 µg/g Cd). Thus, information on the build up of heavy metal concentration in soil and their removal by seasonal weed species grown on sites receiving sewage water indicate risk of metal entry in animal food chain as these weed species except Parthenium are used as a feed for animals. Besides this these weed species can be exploited for phyto-extraction of heavy metals under abiotic stress situation of metalliferrous sites.