AUTHOR=Wang Lihua , Upadhyaya Hari D. , Zheng Jian , Liu Yanlong , Singh Shailesh Kumar , Gowda C. L. L. , Kumar Rajendra , Zhu Yongqun , Wang Yi-Hong , Li Jieqin 

TITLE=Genome-Wide Association Mapping Identifies Novel Panicle Morphology Loci and Candidate Genes in Sorghum

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.743838

DOI=10.3389/fpls.2021.743838

ISSN=1664-462X

ABSTRACT=<p>Panicle morphology is an important trait in racial classification and can determine grain yield and other agronomic traits in sorghum. In this study, we performed association mapping of panicle length, panicle width, panicle compactness, and peduncle recurving in the sorghum mini core panel measured in multiple environments with 6,094,317 single nucleotide polymorphism (SNP) markers. We mapped one locus each on chromosomes 7 and 9 to recurving peduncles and eight loci for panicle length, panicle width, and panicle compactness. Because panicle length was positively correlated with panicle width, all loci for panicle length and width were colocalized. Among the eight loci, two each were on chromosomes 1, 2, and 6, and one each on chromosomes 8 and 10. The two loci on chromosome 2, i.e., <italic>Pm 2-1</italic> and <italic>Pm 2-2</italic>, were detected in 7 and 5 out of 11 testing environments, respectively. <italic>Pm 2-2</italic> colocalized with panicle compactness. Candidate genes were identified from both loci. The rice <italic>Erect Panicle2</italic> (<italic>EP2</italic>) ortholog was among the candidate genes in <italic>Pm 2-2</italic>. <italic>EP2</italic> regulates panicle erectness and panicle length in rice and encodes a novel plant-specific protein with unknown functions. The results of this study may facilitate the molecular identification of panicle morphology-related genes and the enhancement of yield and adaptation in sorghum.</p>