title: Cyto-histological and morpho-physiological responses of common duckweed (Lemna minor L.) to chromium.
abstract: Along with cadmium, lead, mercury and other heavy metals, chromium is an important environmental pollutant, mainly concentrated in areas of intense anthropogenic pressure. The effect of potassium dichromate on Lemna minor populations was tested using the growth inhibition test. Cyto-histological and physiological analyses were also conducted to aid in understanding the strategies used by plants during exposure to chromium. Treatment with potassium dichromate caused a reduction in growth rate and frond size in all treated plants and especially at the highest concentrations. At these concentrations the photosynthetic pathway was also altered as shown by the decrease of maximum quantum yield of photosystem II and the chlorophyll b content and by the chloroplast ultrastructural modifications. Starch storage was also investigated by microscopic observations. It was the highest at the high concentrations of the pollutant. The data suggested a correlation between starch storage and reduced growth; there was greater inhibition of plant growth than inhibition of photosynthesis, resulting in a surplus of carbohydrates that may be stored as starch. The investigation helps to understand the mechanism related to heavy metal tolerance of Lemna minor and supplies information about the behavior of this species widely used as a biomarker.
authors.affiliation: Department of Agricultural, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno 74, 06121 Perugia, Italy. Electronic address: lara.reale@unipg.it.
authors.forename: L
authors.initials: L
authors.lastname: Reale
authors.affiliation: Department of Agricultural, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno 74, 06121 Perugia, Italy. Electronic address: francesco.ferranti@unipg.it.
authors.forename: F
authors.initials: F
authors.lastname: Ferranti
authors.affiliation: Biotecnologie B.T. Srl, Frazione Pantalla di Todi, 06059 Perugia, Italy. Electronic address: smantilacci@biotecnologiebt.it.
authors.forename: S
authors.initials: S
authors.lastname: Mantilacci
authors.affiliation: Biotecnologie B.T. Srl, Frazione Pantalla di Todi, 06059 Perugia, Italy. Electronic address: mcorboli@biotecnologiebt.it.
authors.forename: M
authors.initials: M
authors.lastname: Corboli
authors.affiliation: Biotecnologie B.T. Srl, Frazione Pantalla di Todi, 06059 Perugia, Italy. Electronic address: saversa@biotecnologiebt.it.
authors.forename: S
authors.initials: S
authors.lastname: Aversa
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CVZ-61137 Brno, Czech Republic. Electronic address: flavia.landucci@gmail.com.
authors.forename: F
authors.initials: F
authors.lastname: Landucci
authors.affiliation: Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121 Ferrara, Italy. Electronic address: costanza.baldisserotto@unife.it.
authors.forename: C
authors.initials: C
authors.lastname: Baldisserotto
authors.affiliation: Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121 Ferrara, Italy. Electronic address: lorenzo.ferroni@unife.it.
authors.forename: L
authors.initials: L
authors.lastname: Ferroni
authors.affiliation: Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121 Ferrara, Italy. Electronic address: simonetta.pancaldi@unife.it.
authors.forename: S
authors.initials: S
authors.lastname: Pancaldi
authors.affiliation: Department of Agricultural, Food and Environmental Sciences, University of Perugia, Borgo XX Giugno 74, 06121 Perugia, Italy. Electronic address: roberto.venanzoni@unipg.it.
authors.forename: R
authors.initials: R
authors.lastname: Venanzoni
mesh_terms: D029064:Araceae / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D002734:Chlorophyll / Q000096:biosynthesis; D002857:Chromium / Q000378:metabolism / Q000633:toxicity*; D004785:Environmental Pollutants / Q000378:metabolism / Q000633:toxicity*; D010788:Photosynthesis / Q000187:drug effects; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D013213:Starch / Q000096:biosynthesis
chemical_list: D004785:Environmental Pollutants; D002857:Chromium; D002734:Chlorophyll; C074702:chromium hexavalent ion; D013213:Starch
keywords: Chromium; Growth inhibition test; Lemna minor; Photosystem II; Plastid; Starch