title: Salicylic acid is required for Mi-1-mediated resistance of tomato to whitefly Bemisia tabaci, but not for basal defense to this insect pest.
abstract: Plant defense to pests or pathogens involves global changes in gene expression mediated by multiple signaling pathways. A role for the salicylic acid (SA) signaling pathway in Mi-1-mediated resistance of tomato (Solanum lycopersicum) to aphids was previously identified and its implication in the resistance to root-knot nematodes is controversial, but the importance of SA in basal and Mi-1-mediated resistance of tomato to whitefly Bemisia tabaci had not been determined. SA levels were measured before and after B. tabaci infestation in susceptible and resistant Mi-1-containing tomatoes, and in plants with the NahG bacterial transgene. Tomato plants of the same genotypes were also screened with B. tabaci (MEAM1 and MED species, before known as B and Q biotypes, respectively). The SA content in all tomato genotypes transiently increased after infestation with B. tabaci albeit at variable levels. Whitefly fecundity or infestation rates on susceptible Moneymaker were not significantly affected by the expression of NahG gene, but the Mi-1-mediated resistance to B. tabaci was lost in VFN NahG plants. Results indicated that whiteflies induce both SA and jasmonic acid accumulation in tomato. However, SA has no role in basal defense of tomato against B. tabaci. In contrast, SA is an important component of the Mi-1-mediated resistance to B. tabaci in tomato.
authors.affiliation: Department of Plant Protection,Institute for Agricultural Sciences,Spanish National Research Council (CSIC),Serrano 115 Dpdo.,Madrid 28006,Spain.
authors.forename: C I
authors.initials: CI
authors.lastname: Rodríguez-Álvarez
authors.affiliation: Department of Experimental Sciences,University Jaume I (UJI),Castellón de la Plana 12071,Spain.
authors.forename: M F
authors.initials: MF
authors.lastname: López-Climent
authors.affiliation: Department of Experimental Sciences,University Jaume I (UJI),Castellón de la Plana 12071,Spain.
authors.forename: A
authors.initials: A
authors.lastname: Gómez-Cadenas
authors.affiliation: Department of Nematology,University of California,Riverside,CA 92521,USA.
authors.forename: I
authors.initials: I
authors.lastname: Kaloshian
authors.affiliation: Department of Plant Protection,Institute for Agricultural Sciences,Spanish National Research Council (CSIC),Serrano 115 Dpdo.,Madrid 28006,Spain.
authors.forename: G
authors.initials: G
authors.lastname: Nombela
mesh_terms: D000818:Animals; D005260:Female; D018506:Gene Expression Regulation, Plant / Q000276:immunology*; D006430:Hemiptera / Q000502:physiology*; D018551:Solanum lycopersicum / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D020156:Salicylic Acid
keywords: Bemisia tabaci; Mi-1; Solanum lycopersicum; jasmonic acid (JA); salicylic acid (SA)