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

• Published in: Genetics and molecular biology 2005, Vol.28 (2), p.271-276
• Main Authors: Furlani, Renata Capistrano Moreira, Moraes, Mario Luiz Teixeira de, Resende, Marcos Deon Vilela de, Furlani Junior, Enes, Gonçalves, Paulo de Souza, Valério Filho, Walter Veriano, Paiva, João Rodrigues de
• Format: Article
• Language: English
• Subjects: BIOCHEMISTRY & MOLECULAR BIOLOGY; breeding strategies; effective population size; GENETICS & HEREDITY; linear mixed model; rubber tree improvement
• ISSN: 1415-4757; 1678-4685; 1415-4757; 1678-4685
• DOI: 10.1590/S1415-47572005000200017

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.) Mueell.-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 Selviria, 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.