title: Physiological Traits Associated with Wheat Yield Potential and Performance under Water-Stress in a Mediterranean Environment.
abstract: Different physiological traits have been proposed as key traits associated with yield potential as well as performance under water stress. The aim of this paper is to examine the genotypic variability of leaf chlorophyll, stem water-soluble carbohydrate content and carbon isotope discrimination (Δ(13)C), and their relationship with grain yield (GY) and other agronomical traits, under contrasting water conditions in a Mediterranean environment. The study was performed on a large collection of 384 wheat genotypes grown under water stress (WS, rainfed), mild water stress (MWS, deficit irrigation), and full irrigation (FI). The average GY of two growing seasons was 2.4, 4.8, and 8.9 Mg ha(-1) under WS, MWS, and FI, respectively. Chlorophyll content at anthesis was positively correlated with GY (except under FI in 2011) and the agronomical components kernels per spike (KS) and thousand kernel weight (TKW). The WSC content at anthesis (WSCCa) was negatively correlated with spikes per square meter (SM2), but positively correlated with KS and TKW under WS and FI conditions. As a consequence, the relationships between WSCCa with GY were low or not significant. Therefore, selecting for high stem WSC would not necessary lead to genotypes of GY potential. The relationship between Δ(13)C and GY was positive under FI and MWS but negative under severe WS (in 2011), indicating higher water use under yield potential and MWS conditions.
authors.affiliation: Programa de Investigación de Excelencia Interdisciplinaria, Adaptación de la Agricultura al Cambio Climático (A2C2), Facultad de Ciencias Agrarias, Centro de Mejoramiento Genético y Fenómica Vegetal, Universidad de Talca Talca, Chile.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Del Pozo
authors.affiliation: Programa de Investigación de Excelencia Interdisciplinaria, Adaptación de la Agricultura al Cambio Climático (A2C2), Facultad de Ciencias Agrarias, Centro de Mejoramiento Genético y Fenómica Vegetal, Universidad de TalcaTalca, Chile; Departamento de Ciencias Agrarias, Facultad de Ciencias Agrarias y Forestales, Universidad Católica del MauleCuricó, Chile.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Yáñez
authors.affiliation: Centro Regional Investigación Quilamapu, Instituto de Investigaciones Agropecuarias Chillán, Chile.
authors.forename: Iván A
authors.initials: IA
authors.lastname: Matus
authors.affiliation: Centro Regional Investigación Quilamapu, Instituto de Investigaciones Agropecuarias Chillán, Chile.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Tapia
authors.affiliation: Centro Regional Investigación Quilamapu, Instituto de Investigaciones Agropecuarias Chillán, Chile.
authors.forename: Dalma
authors.initials: D
authors.lastname: Castillo
authors.affiliation: Centro Universitario de la Patagonia, Universidad de Magallanes Coyhiaque, Chile.
authors.forename: Laura
authors.initials: L
authors.lastname: Sanchez-Jardón
authors.affiliation: Unitat de Fisiologia Vegetal, Facultat de Biologia, Universitat de Barcelona Barcelona, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Araus
keywords: carbohydrate; carbon isotope discrimination; chlorophyll; drought; stem reserves