Impact of depth of pedigree and inclusion of historical data on the estimation of additive variance and breeding values in a sugarcane breeding program

Abstract

Sugarcane breeders in Australia combine data across four selection programs to obtain estimates of breeding value for parents. When these data are combined with full pedigree information back to founding parents, computing limitations mean it is not possible to obtain information on all parents. Family data from one sugarcane selection program were analysed using two different genetic models to investigate how different depths of pedigree and amount of data affect the reliability of estimating breeding value of sugarcane parents. These were the parental and animal models. Additive variance components and breeding values estimated from different amounts of information were compared for both models. The accuracy of estimating additive variance components and breeding values improved as more pedigree information and historical data were included in analyses. However, adding years of data had a much larger effect on the estimation of variance components of the population, and breeding values of the parents. To accurately estimate breeding values of all sugarcane parents, a minimum of three generations of pedigree and 5 years of historical data were required, while more information (four generations of pedigree and 7 years of historical data) was required when identifying top parents to be selected for future cross pollination.

Consistency of the results of path analysis among sugarcane experiments

“…This imbalance has led to different precisions in prediction of the genotypic values, even with the use of the REML/BLUP procedure (Barbosa et al 2004). Nevertheless, pedigree information in full-sib families has shown more accurate estimates of genetic parameters (Nunes et al 2008, Atkin et al 2009), indicating that under these conditions, the genetic correlations estimated by mixed models (REML/BLUP) are more precise that the correlations estimated by analysis of variance (Durel et al 1998). As the experiments of half-sib families are balanced, the genetic and phenotypic correlations did not exhibit differences, consequently generating the same results in path analyses ( Table 5), showing that the REML/ BLUP procedures and analysis of variance are equivalent in balanced experiments.…”

Efficiency of selection within sugarcane families via simulated individual BLUP

“…These last two methods use family information for selection and, therefore, are superior in relation to mass selection for traits with family mean heritability higher than individual plant heritability. Family selection has been proven to be essential in sugarcane breeding (Barbosa et al 2004, Atkin et al 2010, Stringer et al 2011). …”

“…However, this method has not been used in sugarcane breeding due to the practical difficulties and uneconomical aspects of obtaining data from individual plants. Otherwise, sugarcane breeding strategies have relied on family selection (Atkin et al 2010, Stringer et al 2011.…”

Genetic divergence among elite sugarcane clones (Saccharum officinarum L.) based on cane yield and quality traits from Northern India

“…The choice of the variety is one of the most important factors in sugarcane breeding and production. Different varieties have different yield potentials, pest and disease resistance and are bred for different ecological and economic conditions (Atkin et al, 2009;Sanghera et al, 2014). Therefore, the establishment of the adequate variety to be grown in a given region is of paramount importance.…”