title: Association Mapping for Aluminum Tolerance in a Core Collection of Rice Landraces.
abstract: Trivalent aluminum (Al3+) has drastic effect on the rice production in acidic soils. Elite genes for aluminum (Al) tolerance might exist in rice landraces. Therefore, the purpose of this research is to mine the elite genes within rice landraces. Association mapping for Al tolerance traits [i.e., relative root elongation (RRE)] was performed by using a core collection of 150 accessions of rice landraces (i.e., Ting's rice core collection). Our results showed that the Ting's rice core collection possessed a wide-range of phenotypic variation for Al tolerance, and the index of Al tolerance (RRE) was ranged from 0.22 to 0.89. Moreover, the groups with different origins and compositions ofindicaandjaponicarice showed different degrees of tolerance to varying levels of Al. These rice landraces were further screened with 274 simple sequence repeat markers, and association mapping was performed using a mixed linear model approach. The mapping results showed that a total of 23 significant (P< 0.05) trait-marker associations were detected for Al tolerance. Of these, three associations (13%) were identical to the quantitative trait loci reported previously, and other 20 associations were reported for the first time in this study. The proportion of phenotypic variance (R2) explained by 23 significant associations ranged from 5.03 to 20.03% for Al tolerance. We detected several elite alleles for Al tolerance based on multiple comparisons of allelic effects, which could be used to develop Al tolerant rice cultivars through marker-assisted breeding.
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research InstituteHangzhou, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural UniversityGuangzhou, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute Hangzhou, China.
authors.forename: Kaizhen
authors.initials: K
authors.lastname: Zhong
authors.affiliation: State Key Laboratory of Rice Biology, China National Rice Research Institute Hangzhou, China.
authors.forename: Hanhua
authors.initials: H
authors.lastname: Tong
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University Guangzhou, China.
authors.forename: Muhammad Qasim
authors.initials: MQ
authors.lastname: Shahid
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural UniversityGuangzhou, China; Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding ResearchCologne, Germany.
authors.forename: Jinquan
authors.initials: J
authors.lastname: Li
keywords: Ting’s core collection; allele effect; association mapping; mixed linear model; relative root elongation; rice aluminum tolerance