Dual Δ¹³C/δ¹⁸O response to water and nitrogen availability and its relationship with yield in field-grown durum wheat.
The combined use of stable carbon and oxygen isotopes in plant matter is a tool of growing interest in cereal crop management and breeding, owing to its relevance for assessing the photosynthetic and transpirative performance under different growing conditions including water and N regimes. However, this method has not been applied to wheat grown under real field conditions. Here, plant growth, grain yield (GY) and the associated agronomic components, carbon isotope discrimination (Δ¹³C) plus oxygen isotope composition (δ¹⁸O) as well as leaf and canopy gas exchange were measured in field-grown wheat subjected to different water and N availabilities. Water limitation was the main factor affecting yield, leaf and canopy gas exchange and Δ¹³C and δ¹⁸O, whereas N had a smaller effect on such traits. The combination of Δ¹³C and δ¹⁸O gave a clear advantage compared with gas exchange measurements, as it provides information on the instantaneous and the long-term plant photosynthetic and transpirative performance and are less labour intensive than gas exchange measurements. In addition, the combination of plant Δ¹³C and δ¹⁸O predicted differences in GY and related agronomical parameters, providing agronomists and breeders with integrative traits for selecting crop management practices and/or genotypes with better performance under water-limiting and N-limiting conditions.
Unitat de Fisiologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
Llorenç
L
Cabrera-Bosquet
Rossella
R
Albrizio
Salvador
S
Nogués
José Luis
JL
Araus
D002247:Carbon Isotopes / Q000032:analysis; D002734:Chlorophyll / Q000032:analysis; D007558:Italy; D009584:Nitrogen / Q000502:physiology*; D010103:Oxygen Isotopes / Q000032:analysis; D010788:Photosynthesis; D018515:Plant Leaves / Q000254:growth & development / Q000502:physiology; D018526:Plant Transpiration; D014908:Triticum / Q000254:growth & development / Q000502:physiology*; D014867:Water / Q000502:physiology*
D002247:Carbon Isotopes; D010103:Oxygen Isotopes; D014867:Water; D002734:Chlorophyll; D009584:Nitrogen