Heritability of floral traits in Allium cepa L. populations from biparental crosses

NOGUERA SERRANO, SORAYA PAOLA; GIMENEZ, MAGALÍ DIANA; PAZ, ROSALÍA CRISTINA; GALMARINI, CLAUDIO R.

CROP SCIENCE

CROP SCIENCE SOC AMER

Año: 2024

0011-183X

Onions (Allium cepaL.) are one of the main vegetable crops worldwide. As an allogamous specieswith entomophilous pollination, floral traits play a critical role in seedproduction. Improving seed yield, especially for hybrid seed production, isvery important. In this work, we obtained genetic information for floral traitsusing segregating populations from three male-sterile lines and oneopen-pollinated variety. Data on 16 floral traits, including perianth,gynoecium, stamens, and receptacle structures, were collected from the parentalcultivars, their hybrids, and from segregating populations in the F2andF3generations. This dataset underpinned a comprehensive analysis of geneticvariability, broad- and narrow-sense heritability estimation, genetic gainpredictions, and trait correlations. The evaluated traits exhibited highbroad-sense heritability values (0.08–0.85), but moderate narrow-senseheritability values (0.01–0.68), implying that the observed phenotypic varianceis mainly explained by genetic factors, with a minor additive genetic factorscontribution. Consequently, the study revealed effective genetic gain for theanalyzed traits. The phenotypic correlations observed in the parental cultivarswere not always maintained in the segregating populations, suggesting randomcorrelations. Mean-while, genetic correlations were moderate to low, suggestingthat the analyzed traits can be independently selected without affecting theexpression of other floral traits. Notably, correlations among floral traitswere significant in stable cultivars but weak in segregating populations,excluding pleiotropic effects. This work has successfully demonstrated theheritability of onion floral traits and provided a sound basis for selectingindividuals with desirable attributes, with valuable practical implications foronion breeding and seed production.