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Factors affecting heterotic grouping with cross‐pollinating crops
Author(s) -
Viana José Marcelo Soriano,
Risso Leonardo Alves,
Oliveira deLima Rodrigo,
Fonseca e Silva Fabyano
Publication year - 2020
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.1002/agj2.20485
Subject(s) - heterosis , biology , genetics , genetic diversity , population , genetic distance , molecular marker , gene , genetic variation , hybrid , botany , demography , sociology
Heterotic grouping based on the analyses of heterosis or combining ability and molecular diversity has not been consistent. The objectives of this study were to investigate the factors affecting heterotic grouping and the significance of the phenotypic and molecular data. We simulated grain yield and molecular data for nine populations, the nine selfed populations, the 36 interpopulation crosses, 225 doubled haploid (DH) lines (25/population), and their 25,200 single crosses. We assumed genetic control by 400 genes and genotyping for 50 and 192 simple sequence repeats (SSR)/single nucleotide polymorphisms (SNP). We assessed heterosis, combining ability, and genetic diversity using a cluster and population structure analyses. We also performed a genetic diversity analysis based on gene frequencies. This analysis revealed seven (clustering) and four (population structure) heterotic groups. Concerning the phenotypic data, there was a consistent result indicating high heterosis between populations with average frequency of the favorable genes of 0.7 and 0.9 and populations with average frequency of the favorable genes of 0.1 and 0.3, and low average intragroup heterosis. This is in agreement with the analysis based on genes. Concerning the molecular data, the correlations between genetic distance with heterosis and specific heterosis were in the range 0.15–0.35 for SSR and in the range −0.14 to 0.01 for SNP. Heterotic grouping is affected by the degree of linkage disequilibrium between genes and molecular markers, the genetic structure of the sample, molecular marker type, measure of genetic divergence, method applied, and criterion for defining the best number of clusters.