Plant-assisted bioremediation (PABR) is a strategy based on interactions between plants and microorganisms in the rhizosphere, which promotes a reduction in soil contaminants. In fact, the plant root system can stimulate microbial activity in the rhizosphere favoring decontamination processes (biodegradation of organic xenobiotics and removal/transformation of the inorganic ones). In the last few years, several laboratory, greenhouse, and field studies were carried out to assess the effectiveness of PABR technology in recovering multi-contaminated soils. At laboratory scale, microcosm experiments allow studying natural soil microbial populations under controlled environmental conditions (e.g., temperature, light, humidity, and so on). Recently, sunflower has been proposed for plant-assisted bioremediation purposes. This plant species was demonstrated to be able to absorb various heavy metals (e.g., Zn, Cu, Pb, etc) through its root system. Moreover, sunflower effectiveness in degradation of Persistent Organic Pollutants (e.g., DDT, endosulfan, different chlorinated compounds, and polychlorinated biphenyl-PCBs) was verified recently. In this work, a sunflower microcosm experiment was carried out for 3 months to assess sunflower capability in restoring soil historically contaminated by PCBs and heavy metals (HM). The soil was collected from a survey site located close to Taranto city (Southern Italy). Four different experimental conditions (presence/absence of compost and/or plant) have been set up. Chemical analyses of soil properties (e.g., pH, EC, OC, available phosphorous) and pollutants (PCBs and HMs) were performed at two sampling times (45, 90 days). Moreover, microbial abundance, dehydrogenase activity, and qPCR assays were performed for evaluating the autochthonous microbial community composition, structure, and functioning. Finally, a root exudates screening was carried out on planted pots in order to investigate the potential microbial-plant interactions occurring in sunflower-assisted bioremediation microcosm experiments.
Assessment of Sunflower Capability in Restoring Soil Contaminated by PCBs and HMs in Microcosm Experiments
Valeria Ancona;Ida Rascio;Giorgia Aimola;Paola Grenni;Gian Luigi Garbini;Vito Locaputo;Angela Gatto;Marina Tumolo;Daniela Losacco;Anna Barra Caracciolo
2022
Abstract
Plant-assisted bioremediation (PABR) is a strategy based on interactions between plants and microorganisms in the rhizosphere, which promotes a reduction in soil contaminants. In fact, the plant root system can stimulate microbial activity in the rhizosphere favoring decontamination processes (biodegradation of organic xenobiotics and removal/transformation of the inorganic ones). In the last few years, several laboratory, greenhouse, and field studies were carried out to assess the effectiveness of PABR technology in recovering multi-contaminated soils. At laboratory scale, microcosm experiments allow studying natural soil microbial populations under controlled environmental conditions (e.g., temperature, light, humidity, and so on). Recently, sunflower has been proposed for plant-assisted bioremediation purposes. This plant species was demonstrated to be able to absorb various heavy metals (e.g., Zn, Cu, Pb, etc) through its root system. Moreover, sunflower effectiveness in degradation of Persistent Organic Pollutants (e.g., DDT, endosulfan, different chlorinated compounds, and polychlorinated biphenyl-PCBs) was verified recently. In this work, a sunflower microcosm experiment was carried out for 3 months to assess sunflower capability in restoring soil historically contaminated by PCBs and heavy metals (HM). The soil was collected from a survey site located close to Taranto city (Southern Italy). Four different experimental conditions (presence/absence of compost and/or plant) have been set up. Chemical analyses of soil properties (e.g., pH, EC, OC, available phosphorous) and pollutants (PCBs and HMs) were performed at two sampling times (45, 90 days). Moreover, microbial abundance, dehydrogenase activity, and qPCR assays were performed for evaluating the autochthonous microbial community composition, structure, and functioning. Finally, a root exudates screening was carried out on planted pots in order to investigate the potential microbial-plant interactions occurring in sunflower-assisted bioremediation microcosm experiments.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
