title: Ozonated water reduces susceptibility in tomato plants to Meloidogyne incognita by the modulation of the antioxidant system.
abstract: Few studies have been carried out on the effect of ozonated water (O3wat) on the oxidative stress of root systems and, in particular, in combination with biotic stress. The aim of this study was to determine whether aqueous ozone is effective in the control of root-knot nematode (RKN) infection and to investigate the concomitant changes in the basal defence system. A tomato cultivar susceptible to Meloidogyne incognita was treated with O3wat as a soil drench. No negative effects were seen following ozone application in comparison with the control under the exposure conditions used. The treatment reduced significantly the nematode infection rate and induced changes in the morphology of nematode feeding sites, some of which were characterized by visible symptoms of senescence. The antioxidant response, as well as parameters of oxidative damage, were examined in untreated and O3wat-treated galls at 2, 4 and 7 days after inoculation and compared with uninfected roots. High levels of reactive oxygen species (ROS), H2O2and malondialdehyde were generated in galls in response to combined abiotic and biotic stresses. Throughout the experimental period, the activities and relative transcript levels of the antioxidant enzymes catalase, superoxide dismutase and ascorbate peroxidase produced different responses when exposed to ozone treatment and/or infection. The results demonstrate how O3wat protects tomato against the RKN M. incognita through the modulation of basal defence mechanisms.
authors.affiliation: CNR, Istituto per la Protezione Sostenibile delle Piante, Bari, 70126, Italy.
authors.forename: Pasqua
authors.initials: P
authors.lastname: Veronico
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Bari 'Aldo Moro', Bari, 70126, Italy.
authors.forename: Costantino
authors.initials: C
authors.lastname: Paciolla
authors.affiliation: CNR, Istituto per la Protezione Sostenibile delle Piante, Bari, 70126, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Sasanelli
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Bari 'Aldo Moro', Bari, 70126, Italy.
authors.forename: Silvana
authors.initials: S
authors.lastname: De Leonardis
authors.affiliation: CNR, Istituto per la Protezione Sostenibile delle Piante, Bari, 70126, Italy.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Melillo
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D004198:Disease Susceptibility; D005247:Feeding Behavior / Q000187:drug effects; D006790:Host-Parasite Interactions / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D018551:Solanum lycopersicum / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000469:parasitology*; D008315:Malondialdehyde / Q000378:metabolism; D010126:Ozone / Q000494:pharmacology*; D010935:Plant Diseases / Q000469:parasitology*; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D012987:Soil; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D014431:Tylenchoidea / Q000187:drug effects / Q000472:pathogenicity*; D014867:Water / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D012333:RNA, Messenger; D012987:Soil; D014867:Water; D008315:Malondialdehyde; D010126:Ozone; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase
keywords: M. incognita; antioxidant systems; defence inducer; feeding sites; molecular responses; oxidative stress; ozone