Dataset Information

Population structure analysis and identification of genomic regions under selection associated with low-nitrogen tolerance in tropical maize lines.

ABSTRACT: Increasing low nitrogen (N) tolerance in maize is an important goal for food security and agricultural sustainability. In order to analyze the population structure of tropical maize lines and identify genomic regions associated with low-N tolerance, a set of 64 inbred lines were evaluated under low-N and optimal-N conditions. The low-N Agronomic Efficiency index (LNAE) of each line was calculated. The maize lines were genotyped using 417,112 SNPs markers. The grouping based on the LNAE values classified the lines into two phenotypic groups, the first comprised by genotypes with high LNAE (named H_LNAE group), while the second one comprised genotypes with low LNAE (named L_LNAE group). The H_LNAE and L_LNAE groups had LNAE mean values of 3,304 and 1,644, respectively. The population structure analysis revealed a weak relationship between genetic and phenotypic diversity. Pairs of lines were identified, having at the same time high LNAE and high genetic distance from each other. A set of 29 SNPs markers exhibited a significant difference in allelic frequencies (Fst > 0.2) between H_LNAE and L_LNAE groups. The Pearson's correlation between LNAE and the favorable alleles in this set of SNPs was 0.69. These SNPs could be useful for marker-assisted selection for low-N tolerance in maize breeding programs. The results of this study could help maize breeders identify accessions to be used in the development of low-N tolerant cultivars.

SUBMITTER: Sant'Ana GC

PROVIDER: S-EPMC7523979 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Population structure analysis and identification of genomic regions under selection associated with low-nitrogen tolerance in tropical maize lines.

Sant'Ana Gustavo César GC Espolador Fernando Garcia FG Granato Ítalo Stefanine Correia ÍSC Mendonça Leandro Freitas LF Fritsche-Neto Roberto R Borém Aluízio A

PloS one 20200929 9

Increasing low nitrogen (N) tolerance in maize is an important goal for food security and agricultural sustainability. In order to analyze the population structure of tropical maize lines and identify genomic regions associated with low-N tolerance, a set of 64 inbred lines were evaluated under low-N and optimal-N conditions. The low-N Agronomic Efficiency index (LNAE) of each line was calculated. The maize lines were genotyped using 417,112 SNPs markers. The grouping based on the LNAE values cl ...[more]

PMID: 32991596

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Dataset Information

Population structure analysis and identification of genomic regions under selection associated with low-nitrogen tolerance in tropical maize lines.

Publications

Population structure analysis and identification of genomic regions under selection associated with low-nitrogen tolerance in tropical maize lines.

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