title: Salinity-Induced Variation in Biochemical Markers Provides Insight into the Mechanisms of Salt Tolerance in Common (Phaseolus vulgaris) and Runner (P. coccineus) Beans.
abstract: The evaluation of biochemical markers is important for the understanding of the mechanisms of tolerance to salinity ofPhaseolusbeans. We have evaluated several growth parameters in young plants of threePhaseolus vulgariscultivars subjected to four salinity levels (0, 50, 100, and 150 mM NaCl); one cultivar ofP. coccineus, a closely related species reported as more salt tolerant than common bean, was included as external reference. Biochemical parameters evaluated in leaves of young plants included the concentrations of ions (Na⁺, K⁺, and Cl-), osmolytes (proline, glycine betaine, and total soluble sugars), and individual soluble carbohydrates. Considerable differences were found among cultivars, salinity levels, and in their interaction for most traits. In general, the linear component of the salinity factor for the growth parameters and biochemical markers was the most important. Large differences in the salinity response were found, withP. vulgariscultivars "The Prince" and "Maxidor" being, respectively, the most susceptible and tolerant ones. Our results support that salt stress tolerance in beans is mostly based on restriction of Na⁺ (and, to a lesser extent, also of Cl-) transport to shoots, and on the accumulation ofmyo-inositol for osmotic adjustment. These responses to stress during vegetative growth appear to be more efficient in the tolerantP. vulgariscultivar "Maxidor". Proline accumulation is a reliable marker of the level of salt stress affectingPhaseolusplants, but does not seem to be directly related to stress tolerance mechanisms. These results provide useful information on the responses to salinity ofPhaseolus.
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC), 46022 Valencia, Spain. moalhas@posgrado.upv.es.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Al Hassan
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC), 46022 Valencia, Spain. mihaela.morosan@mail.com.|Faculty of Horticulture, University of Agricultural Sciences and Veterinary Medicine (USAMV), 400372 Cluj-Napoca, Romania. mihaela.morosan@mail.com.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Morosan
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC), 46022 Valencia, Spain. mplopez@ceqa.upv.es.
authors.forename: María Del Pilar
authors.initials: MD
authors.lastname: López-Gresa
authors.affiliation: Instituto de Conservación y Mejora de la Agrodiversidad Valenciana, Universitat Politècnica de València (UPV), 46022 Valencia, Spain. jprohens@btc.upv.es.
authors.forename: Jaime
authors.initials: J
authors.lastname: Prohens
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC), 46022 Valencia, Spain. ovicente@ibmcp.upv.es.
authors.forename: Oscar
authors.initials: O
authors.lastname: Vicente
authors.affiliation: Instituto Agroforestal Mediterráneo, Universitat Politècnica de València (UPV), 46022 Valencia, Spain. mobosnea@eaf.upv.es.
authors.forename: Monica
authors.initials: M
authors.lastname: Boscaiu
keywords: Phaseolus; ions concentration; myo-inositol; osmotic adjustment; proline; salt tolerance