Author
![]() |
ZHAO, XINXIN - Sichuan Agricultural University |
![]() |
Bushman, Bradley |
![]() |
ZHANG, XINQUAN - Sichuan Agricultural University |
![]() |
Robbins, Matthew |
![]() |
Larson, Steven |
![]() |
Robins, Joseph |
![]() |
THOMAS, AARON - Utah State University |
Submitted to: Plant Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/3/2017 Publication Date: 10/7/2017 Citation: Zhao, X., Bushman, B.S., Zhang, X., Robbins, M.D., Larson, S.R., Robins, J.G., Thomas, A. 2017. Association of candidate genes with heading date in a diverse Dactylis glomerata population. Plant Science. 265:146-153. https://doi.org/10.1016/j.plantsci.2017.10.002. DOI: https://doi.org/10.1016/j.plantsci.2017.10.002 Interpretive Summary: Heading date is a major breeding objective in orchardgrass, affecting forage nutritive quality, abiotic stress tolerance, and timing of hay or silage harvest in mixed pastures with perennial legumes. Flowering occurs in response to cues from both temperature and photoperiod elicitors in long-day forage grasses, and genes involved in sensing the elicitors and inducing downstream flowering responses have been associated with heading date and flowering time. In this study, we test for association between orchardgrass heading date and polymorphisms in the CONSTANS (DgCO1), FLOWERING TIME (DgFT1), PHOTOPERIOD (DgPPD1-like), and MADS-box (DgMADS) containing genes. A diverse population of 154 plants was phenotyped across three years, genotyped, and the candidate genes sequenced. Intro-population relationships were accounted for, linkage disequilibrium within the genes decayed rapidly. Polymorphic sites significantly associated with heading date were detected in DgCO1, DgPPD1-like, and DgMADS. The DgCO1 gene had the most significant polymorphisms, which can be used for further validation, selection, and development of breeding lines of orchardgrass. Technical Abstract: Heading date is a major breeding objective in orchardgrass, affecting forage nutritive quality, abiotic stress tolerance, and timing of hay or silage harvest in mixed pastures with perennial legumes. Flowering occurs in response to cues from both temperature and photoperiod elicitors in long-day forage grasses, and genes involved in sensing the elicitors and inducing downstream flowering responses have been associated with heading date and flowering time. In this study, we test for association between orchardgrass heading date and polymorphisms in the CONSTANS (DgCO1), FLOWERING TIME (DgFT1), PHOTOPERIOD (DgPPD1-like), and MADS-box (DgMADS) containing genes. A diverse population of 154 plants was phenotyped across three years, genotyped, and the candidate genes sequenced. Intro-population relationships were accounted for, linkage disequilibrium within the genes decayed rapidly. Polymorphic sites significantly associated with heading date were detected in DgCO1, DgPPD1-like, and DgMADS. The DgCO1 gene had the most significant polymorphisms, which can be used for further validation, selection, and development of breeding lines of orchardgrass. |