|WANG, RUI - University Of Idaho|
|LIU, YUXIU - University Of Idaho|
|ISHAM, KYLE - University Of Idaho|
|ZHAO, WEIDONG - University Of Idaho|
|WHEELER, JUSTIN - University Of Idaho|
|KLASSEN, NATALIE - University Of Idaho|
|HU, YINGANG - Northwest Agriculture And Forestry University|
|CHEN, JIANLI - University Of Idaho|
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/18/2018
Publication Date: 11/1/2018
Citation: Wang, R., Liu, Y., Isham, K., Zhao, W., Wheeler, J., Klassen, N., Hu, Y., Bonman, J.M., Chen, J. 2018. QTL identification and KASP markers development for productive tiller and fertile spikelet numbers in two high yielding hard white spring wheat cultivars. Molecular Breeding. 38:135. https://doi.org/10.1007/s11032-018-0894-y.
Interpretive Summary: Breeding for increased yield is a primary goal of wheat breeding programs. Two important components of yield are the number of productive tillers per unit area and the number of fertile spikelets per wheat spike (or head). In this study we determined the inheritance of these two traits using well-adapted spring wheat cultivars as parents. We discovered novel loci for these traits on two wheat chromosomes and developed 'user-friendly' molecular markers that can be used in breeding. These discoveries will aid wheat breeders in efforts to generate new, high-yielding wheat cultivars.
Technical Abstract: Selecting high-yielding wheat cultivars with more productive tillers per unit area (PTN) combined with more fertile spikelets per spike (fSNS) is difficult. QTL mapping of these traits may aid understanding of this bottleneck and accelerate precision breeding for high yield via marker-assisted selection. PTN and fSNS were assessed in four to five trials from 2015 to 2017 in a doubled haploid population derived from two high-yielding cultivars “UI Platinum” and “SY Capstone”. Two QTL for PTN (QPTN.uia-4A and QPTN.uia-6A) and four QTL for fSNS (QfSNS.uia-4A, QfSNS.uia-5A, QfSNS.uia-6A, and QfSNS.uia-7A) were identified. The effects of the QTL were primarily additive and, therefore, pyramiding of multiple QTL may increase PTN and fSNS. However, the two QTL for PTN were positioned in the flanking regions for the two QTL for fSNS on chromosome 4A and 6A, respectively, suggesting possible pleiotropic effect of the same QTL or tightly linked QTL and explaining the difficulty of selecting both high PTN and fSNS in phenotypic selection. Kompetitive allele-specific PCR (KASP) markers for these QTL and QTL pairs were developed and validated in the recombinant inbred lines derived from the same two hard white cultivars. These KASP markers could be used by wheat breeders to select the increased PTN and fSNS.