Genetic Variation and Effective Population Size in Dipteryx Alata Progenies in Pederneiras, São Paulo, Brazil

Abstract

Genetic and phenotypic parameters of fork (BIF), stem form (RET) and diameter at breast height (DBH) for Dipteryx alata provenances and progenies were assessed. The trial was lead in a randomized block design, with 43 treatments (26 and 17 progenies from the municipalities of Três Lagoas and Brasília in the state of Mato Grosso do Sul and Distrito Federal, Brazil, respectively) and five plants per plot. The spacing between plants was 3 x 3 meters. The data analysis was performed using the REML/BLUP method (restricted maximum likelihood best linear unbiased prediction). Significant differences were detected between progenies only for DBH. The individual genetic values ranged from 3.7 to 21.7 % for BIF and DBH; genetic variation among progenies ranged from 9 to 10.5 % for BIF and DBH among provenances. Individual heritability in the strict sense was high for DBH (minimum from 0.31), revealing the potential for genetic improvement. Provenance and progenies trial showed genetic variability which can be exploited in forest improvement programs with a broad genetic base.

Classifying coefficients of genetic variation and heritability for Eucalyptus spp.

“…However, to understand the genetic variation existing in experiments using progenies or clones, two coefficients are generally used: coefficients of genetic variation (CV g , CV gi ), based on the method described by Burton (1952); and coefficients of heritability (h 2 g , h 2 a ) defined between 1918 and 1940 by Fisher, Wright, and Lush (Visscher et al 2008). To ensure success in the selection of genetic materials with desirable traits, coefficients of genetic variation help to identify, quantify, and compare the genetic variability of traits that can be maintained, thus making inferences about the possible outcomes of selection (Resende 1991, Houle 1992, Santos et al 2018. Along with heritability coefficients, which offer estimates of the genetic contribution for each trait or quantify the genetic origins of phenotypic variation, it is possible to infer and analyze the proportion of traits that are inherited, the genetic control over traits, and the impact of non-heritable factors, such as environmental effects.…”