Identification and analysis of the gene network involved in phosphorus uptake in maize

Context Phosphorus deficiency is a limiting factor affecting plant growth, development, and yield. Aims This study aimed to evaluate the Iranian maize (Zea mays) germplasm in response phosphorus deficiency and identify genomic loci involved in the response. Methods Using a maize 600K Single Nucleotide Polymorphism (SNP) array followed by gene network analysis, a genetic analysis of phosphorus uptake of 93 maize genotypes was evaluated in optimal and phosphorus-deficient conditions. After filtering for a minor allele frequency below 10%, 450,133 SNPs were retained to investigate phosphorus uptake efficiency. Key results In both optimal and deficient phosphorus states, seven candidate genes were identified that corresponded with disease resistance proteins (e.g. RPM1 and RPP13), cellular component proteins (e.g. RER3), molecular functional protein (e.g. SF3B4), and other proteins including HVA22-like protein c and PPR. Genes RPM1 and RPP13 interacted with RIN genes that act as essential regulators of the plant defence system. The candidate gene HVA22C could interact with other HVA22 genes to protect cells against environmental stresses. Conclusions The identified candidate genes play roles in the abscisic acid signalling pathway, mesophyll cell division, plant defence regulation against pathogens, and chloroplast RNA processing. This preliminary study offered valuable insights, but further validation is needed before drawing definitive conclusions. Implications There was genetic variability for phosphorus uptake among the Iranian maize germplasm and the identified genes could applied in future breeding programs of maize to better understand the molecular response to phosphorus deficiency in the development of more phosphorus-efficient maize genotypes.