title: Variation in salinity tolerance of four lowland genotypes of quinoa (Chenopodium quinoa Willd.) as assessed by growth, physiological traits, and sodium transporter gene expression.
abstract: Chenopodium quinoa (Willd.) is an Andean plant showing a remarkable tolerance to abiotic stresses. In Chile, quinoa populations display a high degree of genetic distancing, and variable tolerance to salinity. To investigate which tolerance mechanisms might account for these differences, four genotypes from coastal central and southern regions were compared for their growth, physiological, and molecular responses to NaCl at seedling stage. Seeds were sown on agar plates supplemented with 0, 150 or 300mM NaCl. Germination was significantly reduced by NaCl only in accession BO78. Shoot length was reduced by 150mM NaCl in three out of four genotypes, and by over 60% at 300mM (except BO78 which remained more similar to controls). Root length was hardly affected or even enhanced at 150mM in all four genotypes, but inhibited, especially in BO78, by 300mM NaCl. Thus, the root/shoot ratio was differentially affected by salt, with the highest values in PRJ, and the lowest in BO78. Biomass was also less affected in PRJ than in the other accessions, the genotype with the highest increment in proline concentration upon salt treatment. Free putrescine declined dramatically in all genotypes under 300mM NaCl; however (spermidine+spermine)/putrescine ratios were higher in PRJ than BO78. Quantitative RT-PCR analyses of two sodium transporter genes, CqSOS1 and CqNHX, revealed that their expression was differentially induced at the shoot and root level, and between genotypes, by 300mM NaCl. Expression data are discussed in relation to the degree of salt tolerance in the different accessions.
authors: Dipartimento di Colture Arboree, Università di Bologna, Bologna, Italy.
authors: Karina
authors: K
authors: Ruiz-Carrasco
authors: Fabiana
authors: F
authors: Antognoni
authors: Amadou Konotie
authors: AK
authors: Coulibaly
authors: Susana
authors: S
authors: Lizardi
authors: Adriana
authors: A
authors: Covarrubias
authors: Enrique A
authors: EA
authors: Martínez
authors: Marco A
authors: MA
authors: Molina-Montenegro
authors: Stefania
authors: S
authors: Biondi
authors: Andrés
authors: A
authors: Zurita-Silva
mesh_terms: D001692:Biological Transport; D018533:Biomass; D027465:Chenopodium quinoa / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D003001:Cloning, Molecular; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D018525:Germination; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D011073:Polyamines / Q000032:analysis / Q000378:metabolism; D011392:Proline / Q000032:analysis / Q000378:metabolism; D011700:Putrescine / Q000032:analysis / Q000378:metabolism; D055049:Salt Tolerance / Q000235:genetics*; D055051:Salt-Tolerant Plants; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology*
chemical_list: D010940:Plant Proteins; D011073:Polyamines; D012965:Sodium Chloride; D011392:Proline; D011700:Putrescine