Genetic variation, heritability and correlations of agro-morphological traits in tall fescue (Festuca arundinacea Schreb.)

Abstract

To study the genetic variation, heritability and genetic correlations of some agro-morphological traits in tall fescue, 25 parents from a genetically broadbase germplasm were polycrossed and their respective half-sib families were generated. Clonally propagated parents and their half-sib families were grown as spaced single plants using a randomized completeblock design with three replications, and observed for seven traits in 2006 and 2007. The estimates of broad-sense heritability h 2 n À Á were moderate to high h 2 b ¼ 0:43 À 0:80 À Á for the traits studied. Narrowsense heritability h 2 n À Á estimates from analyses of progenies and from regression of half-sib (HS) progenies on parents h 2 op suggested that genetic variation for these traits was largely controlled by additive gene action. Association of dry matter yield (DMY) with plant height, number of fertile shoot, curbs width and spring growth was positive and significant. With the exception of number of days to pollination, correlation coefficients of the traits between the parents and offspring were not significant. Based on parentoffspring regression, genetic gain from selection for DMY was high, demonstrating genetic potential for improving this trait. Overall, there was high genetic variation and moderate heritability for most traits in the tall fescue populations evaluated. In conclusion, to improve herbage yield, selection would be more effective based on forage yield components.

Root and physiological characteristics associated with drought tolerance in Iranian tall fescue

“…After developing a broad-based population from polycross of a set of 25 parental tall fescue genotypes (Majidi et al 2009), 24 (eight early-, eight mid-, and eight late-season flowering) genotypes were selected within the progenies based on drought tolerance and susceptibility indices (Ebrahimiyan et al 2012). The genotypes were clonally propagated in a greenhouse and then transferred to the field in March 2011.…”

Narrow sense heritability estimates of bacterial leaf spot resistance in pseudo F2 (F1) population of mulberry (Morus spp.)

“…Therefore, crossing between outbred tree parents can be assimilated to that of F 2 or BC 1 like self pollinated crops (Tulsieram et al 1992). Indeed, phenotypic evaluation of F 1 was also reported in several cross pollinated plants like cassava (Aravanopoulos 2010), tall fescue (Majidi et al 2009) and willows (Owolade 2006). In most trees, subsequent utilization of generated information in advance breeding with third generation pedigree could only be feasible by trait refinement of selected progenies of F 1 (Ben-Hui Leu 1997; Klein 1998).…”

Heritability and genetic correlation in daylily selection

“…This parameter influences the genetic gain by selection and the choice of the best breeding strategy to be adopted (Allard 1971;Zobel and Talbert 1984;Falconer 1987). Heritability estimates provide an indication of the expected response to selection in a segregating population and are useful in designing an effective breeding program (Majidi et al 2009). …”