Abstract
Perennial ryegrass (
Lolium perenne L.) is a widely cultivated cool-season grass species because of its high quality for forage and turf. Susceptibility to freezing damage limits its further use in temperate zones. The objective of this study was to identify candidate genes significantly associated with winter survival and spring regrowth in a global collection of 192 perennial ryegrass accessions. Significant differences in winter survival (WS), percentage of canopy green cover (CGC), chlorophyll index (Chl), and normalized difference vegetation index (NDVI) were found among accessions. After controlling population structure,
LpLEA3 encoding a late embryogenesis abundant group 3 protein and
LpCAT encoding a catalase were associated with CGC and Chl, while
LpMnSOD encoding a magnesium superoxide dismutase and
LpChlCu-ZnSOD encoding a chlorophyll copper-zinc superoxide dismutase were associated with NDVI or Chl.Significant association was also discovered between C-repeat binding factor
LpCBF1b and WS. Three sequence variations identified in
LpCAT, LpMnSOD, and
LpChl Cu-ZnSOD were synonymous substitutions, whereas one pair of adjacent single nucleotide polymorphisms (SNPs) in
LpLEA3 and one SNP in
LpCBFb resulted in amino acid change. The results demonstrated that allelic variation in
LpLEA3 and
LpCBF1b was closely related to winter survival and spring regrowth in perennial ryegrass.
Keywords
Association mapping,
Candidate gene,
Lolium perenne,
Winter survival,
Regrowth
Citation
Yu, Xiaoqing; Pijut, Paula M.; Byrne, Stephen; Asp, Torben; Bai, Guihua; Jiang, Yiwei. 2015. Candidate gene association mapping for winter survival and spring regrowth in perennial ryegrass. Plant Science. 235: 37-45.