title: Genetic dissection of ozone tolerance in rice (Oryza sativa L.) by a genome-wide association study.
abstract: Tropospheric ozone causes various negative effects on plants and affects the yield and quality of agricultural crops. Here, we report a genome-wide association study (GWAS) in rice (Oryza sativa L.) to determine candidate loci associated with ozone tolerance. A diversity panel consisting of 328 accessions representing all subgroups of O. sativa was exposed to ozone stress at 60 nl l(-1) for 7h every day throughout the growth season, or to control conditions. Averaged over all genotypes, ozone significantly affected biomass-related traits (plant height -1.0%, shoot dry weight -15.9%, tiller number -8.3%, grain weight -9.3%, total panicle weight -19.7%, single panicle weight -5.5%) and biochemical/physiological traits (symptom formation, SPAD value -4.4%, foliar lignin content +3.4%). A wide range of genotypic variance in response to ozone stress were observed in all phenotypes. Association mapping based on more than 30 000 single-nucleotide polymorphism (SNP) markers yielded 16 significant markers throughout the genome by applying a significance threshold of P<0.0001. Furthermore, by determining linkage disequilibrium blocks associated with significant SNPs, we gained a total of 195 candidate genes for these traits. The following sequence analysis revealed a number of novel polymorphisms in two candidate genes for the formation of visible leaf symptoms, a RING and an EREBP gene, both of which are involved in cell death and stress defence reactions. This study demonstrated substantial natural variation of responses to ozone in rice and the possibility of using GWAS in elucidating the genetic factors underlying ozone tolerance.
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Ueda
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Frimpong
authors.affiliation: Key Laboratory of Crop Genetics & Physiology of Jiangsu Province, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Yitao
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany.
authors.forename: Elsa
authors.initials: E
authors.lastname: Matthus
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany.
authors.forename: Linbo
authors.initials: L
authors.lastname: Wu
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Höller
authors.affiliation: Campus Klein-Altendorf, University of Bonn, Klein-Altendorf 2, 53359 Rheinbach, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Kraska
authors.affiliation: Institute of Crop Science and Resource Conservation (INRES), University of Bonn, Karlrobert-Kreiten Strasse 13, 53115 Bonn, Germany mfrei@uni-bonn.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Frei
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000393:Air Pollutants / Q000378:metabolism*; D002874:Chromosome Mapping; D014644:Genetic Variation; D055106:Genome-Wide Association Study; D015810:Linkage Disequilibrium; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010126:Ozone / Q000378:metabolism*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide
chemical_list: D000393:Air Pollutants; D010126:Ozone
keywords: Biomass production; EREBP; RING protein.; genome-wide association study (GWAS); leaf symptoms; lignin; ozone; rice (Oryza sativa L.)