Supported by the FAO/IAEA Coordinated Research Project (CRP) on “Selection for greater agronomic water use efficiency in wheat and rice using carbon isotope discrimination” (Research Contract No12651/R1) and the Major State Basic Research Project of China (no. 2006 CB 100 100).
Relationship between Carbon Isotope Discrimination and Grain Yield in Spring Wheat Cultivated under Different Water Regimes
Version of Record online: 11 OCT 2007
Journal of Integrative Plant Biology
Volume 49, Issue 10, pages 1497–1507, October 2007
How to Cite
Xu, X., Yuan, H., Li, S., Trethowan, R. and Monneveux, P. (2007), Relationship between Carbon Isotope Discrimination and Grain Yield in Spring Wheat Cultivated under Different Water Regimes. Journal of Integrative Plant Biology, 49: 1497–1507. doi: 10.1111/j.1672-9072.2007.00562.x
- Issue online: 11 OCT 2007
- Version of Record online: 11 OCT 2007
- Received 20 Aug. 2006 Accepted 10 May 2007
- carbon isotope discrimination;
- spring wheat;
In C3 plants, carbon isotope discrimination (Δ) has been proposed as an indirect selection criterion for grain yield. Reported correlations between Δ and grain yield however, differ highly according to the analyzed organ or tissue, the stage of sampling, and the environment and water regime. In a first experiment carried out in spring wheat during two consecutive seasons in the dry conditions of northwest Mexico (Ciudad Obregon, Sonora), different water treatments were applied, corresponding to the main water regimes available to spring wheat worldwide, and the relationships between Δ values of different organs and grain yield were examined. Under terminal (post-anthesis) water stress, grain yield was positively associated with Δ in grain at maturity and in leaf at anthesis, confirming results previously obtained under Mediterranean environments. Under early (pre-anthesis) water stress and residual moisture stress, the association between grain Δ and yield was weaker and highly depended on the quantity of water stored in the soil at sowing. No correlation was found between Δ and grain yield under optimal irrigation. The relationship between Δ and grain yield was also studied during two consecutive seasons in 20 bread wheat cultivars in the Ningxia region (Northern China), characterized by winter drought (pre-anthesis water stress). Wheat was grown under rainfed conditions in two locations (Guyuan and Pengyang) and under irrigated conditions in another two (Yinchuan and Huinong). In Huinong, the crop was also exposed to salt stress. Highly significant positive associations were found between leaf and grain Δ and grain yields across the environments. The relationship between Δ and yield within environments highly depended on the quantity of water stored in the soil at sowing, the quantity and distribution of rainfall during the growth cycle, the presence of salt in the soil, and the occurrence of irrigation before anthesis. These two experiments confirmed the value of Δ as an indirect selection criterion for yield and a phenotyping tool under post-anthesis water stress (including limited irrigation).