title: Physiological and morphological responses of the root system of Indian mustard (Brassica juncea L. Czern.) and rapeseed (Brassica napus L.) to copper stress.
abstract: Copper (Cu) is an essential microelement for growth and development, but in excess it can cause toxicity in plants. In this comparative study, the uptake and accumulation of Cu as well as the morphological and physiological responses of Indian mustard (Brassica juncea L. Czern.) and rapeseed (Brassica napus L.) roots to Cu treatment were investigated. The possible involvement of redox active molecules (reactive oxygen species and nitric oxide) and modification in cell wall structure associated with Cu-induced morphological responses were also studied. In short- and long-term treatments, B. juncea suffered more pronounced growth inhibition as compared with B. napus. In addition to the shortening of primary and lateral roots, the number and the density of the laterals were also decreased by Cu. Exposure to copper induced nitric oxide generation in the root tips and this event proved to be dependent on the duration of the exposure and on the plant species. In short- and long-term treatments, Indian mustard showed more significant activation of superoxide dismutase (SOD), inhibition of ascorbate peroxidase (APX) and oxidation of ascorbate (AsA) than B. napus. Moreover, H2O2-dependent lignification was also observed in the Cu-exposed plants. In longer term, significant AsA accumulation and callose deposition were observed, reflecting serious oxidative stress in B. juncea. Based on the morphological and physiological results, we conclude that rapeseed tolerates Cu excess better than Indian mustard.
authors.affiliation: Department of Plant Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary. fglgbr@gmail.com
authors.forename: Gábor
authors.initials: G
authors.lastname: Feigl
authors.forename: Devanand
authors.initials: D
authors.lastname: Kumar
authors.forename: Nóra
authors.initials: N
authors.lastname: Lehotai
authors.forename: Nóra
authors.initials: N
authors.lastname: Tugyi
authors.forename: Arpád
authors.initials: A
authors.lastname: Molnár
authors.forename: Attila
authors.initials: A
authors.lastname: Ordög
authors.forename: Agnes
authors.initials: A
authors.lastname: Szepesi
authors.forename: Katalin
authors.initials: K
authors.lastname: Gémes
authors.forename: Gábor
authors.initials: G
authors.lastname: Laskay
authors.forename: László
authors.initials: L
authors.lastname: Erdei
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Kolbert
mesh_terms: D000222:Adaptation, Physiological; D060387:Ascorbate Peroxidases / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D029688:Brassica napus / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D003300:Copper / Q000633:toxicity*; D006861:Hydrogen Peroxide / Q000378:metabolism; D009149:Mustard Plant / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D018517:Plant Roots / Q000033:anatomy & histology / Q000187:drug effects* / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D012989:Soil Pollutants; D003300:Copper; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases; D013482:Superoxide Dismutase; D001205:Ascorbic Acid