Agronomic and physiological responses of Chinese facultative wheat genotypes to high-yielding Mediterranean conditions

• Published in: The Journal of agricultural science 2016-07, Vol.154 (5), p.870-889
• Main Authors: ZHOU, B., ELAZAB, A., BORT, J., SANZ-SÁEZ, Á., NIETO-TALADRIZ, M. T., SERRET, M. D., ARAUS, J. L.
• Format: Article
• Language: English
• Subjects: aboveground biomass; acclimation; Acclimatization; Agricultural management; canopy; carbon; chlorophyll; Crops and Soils Research Papers; Cultivars; Fertility; filling period; genotype; Genotype & phenotype; Genotypes; Grain; Leaves; nitrogen; nitrogen fertilizers; oxygen; physiological response; Physiological responses; Physiology; Plant biology; Selective breeding; stable isotopes; Stomatal conductance; temperature; tillering; Triticum aestivum; Wheat
• ISSN: 0021-8596; 1469-5146; 1469-5146
• DOI: 10.1017/S0021859615000817

Nine wheat genotypes, bred for the high-input agronomical conditions of Henan Province (China), were tested under the high-yielding Mediterranean conditions of Spain. Two cultivars widely grown in the zone were included as controls. Crop growth and leaf chlorophyll (Chl) content, leaf stomatal conductance (g s) and canopy temperature (CT) were measured during the crop cycle and stable carbon (C), oxygen (O) and nitrogen (N) isotope compositions (δ 13C, δ 18O and δ 15N) were analysed on different plant parts. The lower yield of the Chinese genotypes compared with the controls was due to fewer grains/unit area, associated with lower tillering and a plant height clearly below the optimal range. Moreover, Chinese wheat exhibited a lower spike fertility index than the controls, and this was associated with a less compact spike structure. The physiological characteristics that were related to better performance under high-yielding Mediterranean conditions consisted of a higher green aerial biomass, particularly during the reproductive stage, together with more favourable water conditions (higher g s and lower CT and δ 13C), the capacity to take up water during grain fill (higher δ 18O) and a more efficient uptake (lower δ 15N) and utilization (lower leaf N and Chl content) of N fertilizer. It is concluded that Chinese genotypes exhibited a low acclimation capacity to the moderate stress typical of the high-yielding Mediterranean conditions.