100447 Genome-Wide Association Study of Heat Tolerance in Diverse Population of Perennial Ryegrass.

Poster Number 168-1634

See more from this Division: C05 Turfgrass Science
See more from this Session: Turfgrass Breeding, Genetics and Molecular Techniques Poster (includes student competition)

Monday, November 7, 2016
Phoenix Convention Center North, Exhibit Hall CDE

Gang Nie1, Xiaoqing Yu2, Megan Taylor1, Xin Song1, Xingchun Wang3, Xinquan Zhang4 and Yiwei Jiang5, (1)Department of Agronomy, Purdue University, West Lafayette, IN
(2)Agronomy, Iowa State University, Ames, IA
(3)Shanxi Agricultural University, Taigu, China
(4)Department of Grassland Science, Sichuan Agricultural University, Chengdu, China
(5)915 W. State St., Purdue University, West Lafayette, IN
Abstract:
Perennial ryegrass (Lolium perenne L.) is an important cool-season grass species widely cultivated in the temperate regions with high quality for forage and turf. Susceptibility to high temperature in summer limits its broad use around the world. The objective of this study was to identify the significant associations between single nucleotide polymorphisms (SNPs) and heat tolerance traits in diverse perennial ryegrass accessions. Two hundred and seventy-one worldwide accessions were subjected to 35ºC/30ºC (day/night) for 14 days. Significant differences in plant height, tiller number, chlorophyll index (Chl), chlorophyll fluorescence (Fv/Fm), leaf fresh weight, leaf dry weight, and leaf water content (LWC) were found among accessions under control and heat stress. A total of 24,995 SNPs were obtained by genotype-by-sequencing from 271 accessions. After controlling population structure and relative kinship under CMLM model, 12 significant associations (P < 2.0 × 10-6) were identified including 8 markers with Fv/Fm, 1 with Chl and 3 with LWC. Gene annotation search on perennial ryegrass genome sequence identified 5 candidate genes in the region of significant associations. Gene functional verification is being conducted. The results will reveal genetic and molecular mechanisms of heat tolerance and facilitate genetic enhancement of perennial ryegrass germplasm aimed at improved heat tolerance. 

See more from this Division: C05 Turfgrass Science
See more from this Session: Turfgrass Breeding, Genetics and Molecular Techniques Poster (includes student competition)