Multi-locus genome-wide association study for phosphorus use efficiency in a tropical maize germplasm

Area of Science:

• Agricultural Science
• Plant Genetics
• Molecular Biology

Background:

• Phosphorus (P) is a vital macronutrient for maize (Zea mays L.) growth.
• Improving phosphorus use efficiency (PUE) in maize is crucial for reducing reliance on phosphate fertilizers in agriculture.

Purpose of the Study:

• To identify quantitative trait nucleotides (QTNs) and candidate genes associated with PUE in maize.
• To analyze genetic variability and the complex nature of PUE under varying phosphorus conditions.

Main Methods:

• Genome-wide association studies (GWAS) were conducted on 132 maize inbred lines.
• Experiments were performed in greenhouse and field settings with low and normal phosphorus supply.
• Multi-locus GWAS methods were employed to map associated QTNs for 24 evaluated traits.

Main Results:

• Significant genetic variability was observed among maize inbred lines under different phosphorus conditions.
• A total of 306 QTNs were associated with 24 traits related to PUE.
• 186 potential candidate genes, primarily involved in transcription regulation and transport, were identified.

Conclusions:

• The study confirms the complex, quantitative inheritance of PUE in maize.
• Pyramiding favorable alleles identified in this study offers an efficient strategy for molecular breeding to enhance maize PUE.
• Further research is needed to fully elucidate the function and significance of the identified candidate genes in PUE.