Heavy metal tolerance and accumulation of Cd, Cr and Ni by Cannabis sativa L.
- 968 Downloads
Experiments in semi-natural conditions were undertaken to assess hemp metal tolerance and its ability to accumulate cadmium, nickel and chromium. Cannabis sativa was grown in two soils, S1 and S2, containing 27, 74, 126 and 82, 115, 139 μg g−1 of Cd, Ni and Cr, respectively. After two months from germination and at ripeness, no significant alteration in plant growth or morphology was detected. On the contrary, a high hemp reactivity to heavy metal stress with an increase in phytochelatin and DNA content was observed during development, suggesting the Cannabis sativa ability to avoid cell damage by activating different molecular mechanisms. Metals were preferentially accumulated in the roots and only partially translocated to the above-ground tissues. The mean shoot Cd content was 14 and 66 μg g−1 for S1 and S2 soil, respectively. Although not negligible concentrations they were about 100 times lower than those calculated for the hyperaccumulator Thlaspi caerulescens. Similarly Ni uptake was limited if compared with that of the Ni-hyperaccumulator Alyssum murale. Chromium uptake was negligible. As expected on the base of the metal concentration detected in ripe plants, no statistically significant variation in soil metal content was detected after one crop of hemp. Nevertheless, a consistent amount (g) of Cd and Ni is expected to be extracted by 1 ha biomass of hemp (about 10 t) per year and along the time a slow restoration of deeper soil portions can be obtained by its wide root system (at least 0,5 m deep). In addition, the possibilities of growing hemp easily in different climates and using its biomass in non-food industries can make heavy metal contaminated soils productive. This means economical advantage along with a better quality of soil.
Unable to display preview. Download preview PDF.
- Baker A J M, Reeves R D and Hajar A M 1994 Heavy metal accumulation and tolerance in British populations of the metallophyte Thlaspi caerulescens J. And C. Presl (Brassicaceae). New Phytol. 127, 61–68.Google Scholar
- Brooks R R, Chambers M F, Nicks L J and Robinson B H 1998 Phytomining. Trends Plant Sci. 3(9), 359–362.Google Scholar
- Cappelletto P, Brizzi M, Mongardini F, Barberi B, Sannibale M, Nenci G, Poli M, Corsi G, Grassi G and Pasini P 2001 Italy-grown hemp. Yeld, composition and cannabinoid content. Industrial Crops and Products 13(2), 101–113.Google Scholar
- Cavallini A and Natali L 1991 Intraspecific variation of nuclear DNA content in plant species. Caryologia 44(1), 93–107.Google Scholar
- Correia F, Roy D N and Goel K 1998 Pulping of canadian industrial hemp (Cannabis sativa L.) presents some finding of using nonwood sources. Pulp & Paper-Canada 99(9), 39–41.Google Scholar
- Cromack H T H 1998 The effect of cultivar and seed density on the production and fibre content of Cannabis sativa in southern England. Industrial Crops and Products 7(2–3), 205-210.Google Scholar
- Charkowski E 1998 Hemp ‘eats’ Chernobyl waste. In Central Oregon Green Pages, website: www. empirenet.net/empnet/centrorg.htm.Google Scholar
- Cunningham S D, Berti W R and Huang J W1995 Phytoremediation of contaminated soils. Trends Biotech. 13, 393–397.Google Scholar
- Gupta M and Devi S 1995 Uptake and toxicity of cadmium in aquatic ferns. J. Env. Biol. 16(2), 131–136.Google Scholar
- Mediavilla V, Leupin M and Keller A 2001 Influence of the growth stage of industrial hemp on the yeld formation in relation to certain fibre quality traits. Industrial Crops and Products 13(1), 49–56.Google Scholar
- Nedelkoska T V and Doran P M 2000 Characteristics of heavy metal uptake by plant species with potential for phytoremediation and phytomining. Minerals Eng. 13(5), 549–561.Google Scholar
- Robinson B H, Leblanc M, Petit D, Brooks R R, Kirkman J H and Gregg P E H 1998 The potential of Thlaspi caerulescens for phytoremediation of contaminated soils. Plant Soil 203, 47–56.Google Scholar
- Shallari S, Schwartz C, Hasko A and Morel J L 1998 Heavy metals in soils and plants of serpentine and industrial sites of Albania. Sci. Tot. Env. 209, 133–142.Google Scholar
- Struik P C, Amaducci S, Bullard M J, Stutterheim N C, Venturi G and Cromack H T H 2000 Agronomy of fibre hemp (Cannabis sativa L.) in Europe. Industrial Crop and Products 11(2–3), 107-118.Google Scholar
- Tyler G and Olsson T 2001 Plant uptake of major and minor mineral elements as influenced by soil acidity and liming. Plant Soil 230(2), 307–321.Google Scholar
- Watanabe M E 1997 Phytoremediation on the brink of commercialization. Environ. Sci. Technol. 31, 182–186.Google Scholar