Genome-wide association study and metabolic pathway prediction of barrenness in maize as a response to high planting density

Increasing the planting density is one way to enhance grain production in maize. However, high planting density brings about growth and developmental defects such as barrenness, which is the major factor limiting grain yield. In this study, the barrenness was characterized in an association panel comprising 280 inbred lines under normal (67 500 plants ha–1, ND) and high (120 000 plants ha–1, HD) planting densities in 2017 and 2018. The population was genotyped using 776 254 single nucleotide polymorphism (SNP) markers with criteria of minor allele frequency >5% and