Estimation of variance components and prediction of breeding values in rubber tree breeding using the REML/BLUP procedure

Abstract

The present paper deals with estimation of variance components, prediction of breeding values and selection in a population of rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Müell.-Arg.] from Rio Branco, State of Acre, Brazil. The REML/BLUP (restricted maximum likelihood/best linear unbiased prediction) procedure was applied. For this purpose, 37 rubber tree families were obtained and assessed in a randomized complete block design, with three unbalanced replications. The field trial was carried out at the Experimental Station of UNESP, located in Selvíria, State of Mato Grosso do Sul, Brazil. The quantitative traits evaluated were: girth (G), bark thickness (BT), number of latex vessel rings (NR), and plant height (PH). Given the unbalanced condition of the progeny test, the REML/BLUP procedure was used for estimation. The narrow-sense individual heritability estimates were 0.43 for G, 0.18 for BT, 0.01 for NR, and 0.51 for PH. Two selection strategies were adopted: one short-term (ST -selection intensity of 8.85%) and the other long-term (LT -selection intensity of 26.56%). For G, the estimated genetic gains in relation to the population average were 26.80% and 17.94%, respectively, according to the ST and LT strategies. The effective population sizes were 22.35 and 46.03, respectively. The LT and ST strategies maintained 45.80% and 28.24%, respectively, of the original genetic diversity represented in the progeny test. So, it can be inferred that this population has potential for both breeding and ex situ genetic conservation as a supplier of genetic material for advanced rubber tree breeding programs.

Genetic parameters and agronomic evaluation of cassava genotypes

“…Although the PSW trait showed high CVg, its h g 2 was low, with intermediate magnitude for selective (Borges et al, 2010). Among the methods of prediction, BLUP has the ability to maximize selective accuracy (Resende, 2002;Furlani et al, 2005). The estimates obtained for genetic gains for PSW, based on the selection of the five best genotypes, varied from 6.0 to 11.08%, when compared with the general mean of the evaluated sample (Tables 4 and 5).…”

“…The separation of total variation into inheritable and non-inheritable components is fundamental to define the progress and best strategies for selection. Accurate estimates of variation components and determinants for selection, using optimal procedures of estimation and prediction, are important in cassava breeding, enabling maximization of gains via selection (Furlani et al, 2005;Oliveira et al, 2014).…”

<b>Early selection in sugarcane family trials via BLUP and BLUPIS procedures</b> - doi: 10.4025/actasciagron.v35i4.16430

“…BLUP is considered a preferred procedure because it offers more precision for various experimental conditions, and it maximizes the correlation between the true and predicted genotypic values and the predicted genotypic value relative to other methodologies, which is essential for the breeder (FURLANI et al, 2005;PIEPHO et al, 2008;RESENDE, 2002). One important characteristic of the BLUP procedure is the 'shrinkage' effect that shifts the results of the progeny in the direction of the observed mean; this is a desirable statistical property for an estimator with relatively high accuracy (COPAS, 1983).…”

Variabilidade genética e seleção para caracteres de crescimento da seringueira

“…Diversos trabalhos que visam maximizar os ganhos genéticos da seringueira têm sido realizados no Sri Lanka (JAYASEKERA, 1983), Indonésia (DASLIN et al, 1986), Nigéria (ONOKPISE et al, 1986), Índia (MEENATTOR et al, 1991), Malásia (TAN, 1995) e Brasil (GONÇALVES et al, 1998;COSTA et al, 2000 a;GONÇALVES et al, 2005;FURLANI et al, 2005), dentre outros.…”