Genotype-environment interaction in Cordia trichotoma (Vell.) Arráb. Ex Steud. progenies in two different soil conditions

Abstract

Investment in silvicultural techniques is noticeably lacking, especially in breeding programs for non-conventional wood species. Studying genotype × environment interaction (G × E) is essential to the development of breeding programs. Thus, this study aimed to estimate genetic diversity of and the effects of G × E interaction on two progeny tests of Cordia trichotoma, including the estimation of genetic gain and genetic diversity after selection. For the experiment, 30 progenies of C. trichotoma were tested at two sites with differing soil textures. Diameter at breast height (1.30 m above soil surface, dbh-cm), total height, diameter at 30 cm from the soil, first branch height, and survival were all monitored for four years. Statistical deviance, best linear unbiased estimator, and harmonic mean of relative performance of genetic values (MHPRVG) were all calculated to predict breeding values, estimate genetic parameters, and analyze deviance. All quantified traits varied significantly among progenies by soil type, with greatest variation recorded for genetic variability. Heritability of the progenies led to predictions of genetic gain, ranging from 7.73 to 15.45%, for dbh at four years of age. The calculated decrease in genetic diversity after selection showed that this parameter should be monitored in subsequent breeding cycles. G × E was low for all tests. The best-performing progenies proved most stable and best adapted to the different environmental conditions tested.

Keywords

Effective population number / Native species / Productivity / Stability and adaptability / Tree improvement