New Loci Relating to Rice Tiller Angle Traits Discovery Through Genome-Wide Association Analysis.

Tiller angle (TA) is one of the most important agronomic traits that directly affects plant architecture, photosynthetic efficiency, and planting density of rice. Although many quantitative trait loci (QTLs) and associated genes for TA have been identified, the detection of TA QTLs still needs attention. This study used 238 micro-core germplasm populations for genome-wide association analysis (GWAS) of the TA. The frequency distribution of TA presented continuity in 2018 and 2019, with five QTLs designated as qTA1, qTA2, qTA6, qTA9, and qTA12. These QTLs explained phenotypic variation ranging from 5.94 to 12.38%. Among them, qTA2 and qTA6 were new QTLs of TA, and only qTA1 was detected repeatedly in 2 years. Then, 253 germplasm from the 3K Rice Genome Project were used for candidate gene and haplotypes analysis; the results showed that LOC_Os01g67770, LOC_Os02g35180, and LOC_Os09g38130 were the candidate genes of qTA1, qTA2, and qTA9, respectively. These results provided insight into the genetic improvement of plant architecture in rice. [ABSTRACT FROM AUTHOR]