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Synthetic hexaploid wheat (SHW) is a useful genetic resource that can be used to improve the performance of common wheat by transferring favorable genes from a wide range of tetraploid or diploid donors. From the perspectives of physiology, cultivation, and molecular genetics, the use of SHW has the potential to increase wheat yield. Moreover, genomic variation and recombination were enhanced in newly formed SHW, which could generate more genovariation or new gene combinations compared to ancestral genomes. Accordingly, we presented a breeding strategy for the application of SHW—the 'large population with limited backcrossing method'—and we pyramided stripe rust resistance and big-spike-related QTLs/genes from SHW into new high-yield cultivars, which represents an important genetic basis of big-spike wheat in southwestern China. For further breeding applications of SHW-derived cultivars, we used the 'recombinant inbred line-based breeding method' that combines both phenotypic and genotypic evaluations to pyramid multi-spike and pre-harvest sprouting resistance QTLs/genes from other germplasms to SHW-derived cultivars; consequently, we created record-breaking high-yield wheat in southwestern China. To meet upcoming environmental challenges and continuous global demand for wheat production, SHW with broad genetic resources from wild donor species will play a major role in wheat breeding. [ABSTRACT FROM AUTHOR]

Knowledge about the key traits related to genetic gains in grain yield (GY) is necessary for understanding the main yield‐limiting factors and guiding future wheat (Triticum aestivum L.) breeding. The objective of this research was to investigate the genetic progress in GY and the associated physiological traits in popular wheat cultivars released from 1969 to 2012 in southwestern China. Field experiments included eight representative cultivars that were evaluated at three experimental sites for three growing seasons. Grain yield increased at a linear rate of 0.69% or 52.52 kg ha−1 yr−1, which was mainly attributed to the increases in dry matter (DM) accumulation at maturity, harvest index (HI), and thousand‐kernel weight (TKW). The soil and plant analyzer development (SPAD) values of flag and penultimate leaves at anthesis increased with the year of release and were significantly related to GY. Significant genetic gains were made in both nonstructural carbohydrate (NSC) translocation and NSC translocation efficiency from anthesis to maturity, and there was a trend over time towards a high net photosynthetic rate (Pn) of flag leaf and canopy apparent photosynthesis (CAP) at anthesis and at 30 d post‐anthesis (DPA). In addition, the linear increases in N uptake efficiency and N utilization efficiency were both significant and positive related to GY. Therefore, these key physiological traits can be used as selection criteria for further improving yield potential. Our results also reveal the potential for using synthetic hexaploid wheat in high‐yielding wheat breeding. [ABSTRACT FROM AUTHOR]