Heritability and genetic correlation in daylily selection

Abstract

Daylily (Hemerocallis 9 hybrida Hort.) is a popular ornamental plant and hybrid cultivars are frequently selected for medium size, large number of flowers per stem, and flower color diversity. However, daylily selection is limited due to the lack of information on genetic parameters and their correlation to phenotypic characteristics. This study aimed at estimating genetic parameters and genetic correlations among full sib families of 13 daylily cultivars using REML/BLUP (restricted maximum likelihood/ best linear unbiased prediction) and to select families with high genotypic values for plant height and number of floral buds per stem. Crosses were performed among those cultivars and 24 families were obtained. In the third year, plant height, leaf length and width, stem number, number of floral buds per stem, and number of floral buds per plant were evaluated. The estimates of average heritability of families were superior to the estimates of restrict individual heritability for all characters evaluated. High heritability estimates were obtained for plant height, leaf length, leaf width, stem number, and number of floral buds per plant. Selected families showed genetic gain of 19.80% for plant height, 32.48% for stem number, and 38.64% for number of floral buds per plant.

Genome-Wide Search for Quantitative Trait Loci Controlling Important Plant and Flower Traits in Petunia Using an Interspecific Recombinant Inbred Population ofPetunia axillarisandPetunia exserta

“…The H 2 values of petunia FC ( H 2 = 0.36), PS ( H 2 = 0.53), and PZ ( H 2 = 0.47) were first reported in this study. In other ornamental species, similar or higher H 2 values for FC were reported in Dimorphotheca pluvialis ( H 2 = 0.29) ( Hof et al 1999 ), daylily ( H 2 = 0.67) ( Fogaça et al 2012 ), and rose ( H 2 = 0.74) ( Liang et al 2017 ), and a lower H 2 value for PZ was observed in Viola sororia ( H 2 = 0.36) ( Antlfinger et al 1985 ). The lower H 2 for petunia FC observed in this study indicated that selection for higher FC in progeny of P. axillaris × P. exserta may be less effective than in other plants with higher H 2 values for flower count.…”

Effective population size and genetic gain expected in a population of Coffea canephora

“…The literature also shows plant breeding projects in which base populations were composed of a small number of progenies without compromising their genetic variability. This finding is also confirmed by Gouvea et al (2013) and Oliveira et al (2014), who studied initial populations consisting of 22 and 30 progenies of rubber tree, respectively, and in studies by Fogaça et al (2012), in which the base population consisted of 24 progenies of daylily (Hemerocallis x hybrids Hort.). It should be remembered that one of the limiting factors of allocating a large number of progenies in experiments of perennial crops is the maintenance cost of this population during the 365 days of the year.…”

Phenotypic Variations and Heritability in Hybrid Populations of Bearded Iris

“…If the heritability value is very small or close to zero, there is no genetic variability, and the differences among individuals are likely a result of environmental factors (Falconer, 1989). According to the classification method proposed by Fogaca et al (2012), heritability at an individual level can be considered low when it is less than 0.15; medium, when between 0.15 and 0.50; and high, when greater than 0.50. Traits with high heritability, considerable phenotypic correlation, and low seasonal variability can be candidates for further improvement (Sabu et al, 2009).…”