c5.3.1 – Physiological and biochemical aspects of poplar responses to heavy metals

Tognetti R* (1), Di Baccio D (2), Giochetti G (2), Minnocci A (2), Sebastiani L (2)

(1) Dip. Scienze Animali, Vegetali e dell’Ambiente, Univ. MOL, v. De Sanctis, 86100 Campobasso – (2) Scuola Superiore ‘Sant’Anna’ di Studi Universitari e di Perfezionamento, Piazza Martiri della Libertà 33, 56127 Pisa
Collocazione: c5.3.1 – Tipo Comunicazione: Presentazione orale
5° Congresso SISEF *
Sessione 3: “Metabolismo secondario, fattori di stress e strategie di mitigazione” *

Contatto: R Tognetti (tognetti@unimol.it)

Abstract: Heavy metals are natural constituents of the Earth’s crust, but human-induced land use changes have drastically altered their geochemical cycles and biochemical balance. Actually, large areas of land are contaminated with heavy metals deriving from urban activities (municipal sewage and waste incinerators), agricultural operations (fertilisers and pesticides) and industrial processing (metalliferous mining, smelting industry, paint factory and tannery). Studies on physiological and biochemical responses to heavy metals have got insights from using annual herbaceous plant models. However, results obtained on hyperaccumulators cannot readily be translated to practical use because these plants accumulate low biomass and have slow growth. Rapid growth, high biomass, relatively small genome, simple transformation and propagation techniques are several properties that make Populus (poplars, cottonwoods, aspens) suitable for studying the effect of environmental stresses. Populus systems are also good candidates for being used in phytoremediation, a decontaminating low-cost technique that exploits plants to stabilize, extract and sequester, or detoxify pollutants in soils. Among these, heavy metals are stable and persistent in the environment, as they cannot be degraded or destroyed. A prerequisite for choosing Populus as a model for woody plant research in phytoremediation is to study their genetic background in terms of accumulation capacity and physiological tolerance to heavy metals. Physiological and biochemical studies were started to elucidate the interaction between Populus genotypes and heavy metals. The final aim of these trials was to assess the potential of phytoremediation to treat heavy metal contaminated soils. The poplar tree (genus Populus, family Salicaceae) is one of the most studied woody plants, due to its potential for pulp and paper production, and its particular usefulness in phytoremediation; e.g., fast growth, large transpiration flux, and re-growth from cut stems. Small trees used for in vivo degradation experiments were produced from dormant cuttings of hybrid poplar trees and grown in different model systems. Plant growth, photosynthetic parameters, heavy metal uptake and partitioning, and biochemical and molecular aspects of glutathione biosynthesis and redox status were investigated. Here we report main findings of recent experiments.

Citazione: Tognetti R , Di Baccio D , Giochetti G , Minnocci A , Sebastiani L (2005). Physiological and biochemical aspects of poplar responses to heavy metals . 5° Congresso Nazionale SISEF, Grugliasco (TO), 27 – 29 Set 2005, Contributo no. #c5.3.1