Predicted genetic gains for growth traits and genotype x environment interaction in pinus greggii: New perspectives for genetic improvement in brazil L. Munhoz, Fabricio A Biernaski, F. S. B. Peres, A. N. Dias, E. Tambarussi Anais Da Academia Brasileira De Ciencias, 2021 Pinus greggii has potential for inclusion in temperate zone breeding programs around the world as it is frost resistant and produces high yields for pulp production. This study estimates the genetic parameters for two P. greggii progeny tests established in Telêmaco Borba, Paraná, Brazil. We evaluated diameter at breast height (DBH) and total height (H) at seven and nine years of age. The narrow-sense heritability ( h i 2 ) ranged from 0.225 (H, 7 years) to 0.515 (H, 9 years). The genetic correlation was high for all traits, reaching up to 0.91 between traits and 0.94 between ages. In addition, the results show the presence of Genotype x Environment interaction, and as such, the most productive and stable progeny were identified based on the Harmonic Mean of the Relative Performance of Genetic Values (MHPRVG) values. These population has genetic materials that are superior in terms of both DBH and H compared to the control and to P. greggii materials analyzed internationally. Our results contribute to the literature by providing further genetic information on this species, while also demonstrating the implications of thinning for genetic gains and effective population size.
Using a coalescent approach to assess gene flow and effective population size of Acrocomia aculeata (Jacq.) Lodd. Ex Mart. in the Brazilian Atlantic Forest Renan Marcelo Portela, Evandro Vagner Tambarussi, Ananda Virginia de Aguiar, Flávio B. Gandara, Fabiana Schmidt Bandeira Peres, et al. Tree Genetics and Genomes, 2020 Acrocomia aculeata is a tropical palm tree native to Central and South America that has significant economic, social, and environmental potential. However, land encroachment due to the expansion of agribusiness, and other factors such as urban sprawl, have resulted in the fragmentation and destruction of its habitat, leading to the loss of genes and genotypes in A. aculeata populations. In this context, the objective of this study was to characterize the genetic variability of A. aculeata populations by estimating gene flow and effective population size using an approach based on coalescent theory. Four populations located in the municipalities of Teodoro Sampaio (TSI and TSII), Rosana (RA), and Amparo (AP) in São Paulo State, Brazil, were genotyped with nine microsatellite markers. Gene flow and effective population size were estimated using a coalescent-based Bayesian inference implemented in the MIGRATE-N software. The effective population size (Ne) was obtained considering an assumed mutation rate of 5 × 10−5. Gene flow (Nm) for pairwise populations ranged from 0.28 to 1.17, with higher levels of migration between the three geographically proximal locations (TSI, TSII, and RA). The estimates of effective population size (Ne) were 444, 835, 838, and 874 for AP, TSII, RA, and TSI, respectively, showing that the effects caused by genetic drift may be more pronounced when Ne is smaller. The coalescent-based results add to our understanding of A. aculeata population genetics and suggest that some traditional assessment methods may be ineffective in characterizing historical evolutionary processes.
Adaptation of cedro-vermelha, taruma-azeitona, inga-doce, branquilho-bravo and ocotea-guaica seedlings to shading levels Alexandre Techy de Almeida Garrett, Fabiana Schmidt Bandeira Peres, Mario Takao Inoue, Flávio Augusto de Oliveira Garcia Floresta E Ambiente, 2020 As native tree species are often used for densification, enrichment and degraded areas recovery, a better understanding of the behavior of their seedlings in response to light exposure is needed. This study evaluates the growth and morphological behavior of five native forest species of the Brazilian Mixed Ombrophilous Forest under shading levels of 90%, 50%, and 0%. The species were measured for height to root collar diameter (RCD) ratio (H:D), leaf area (LA), Dickson’s quality index (DQI), and stem, leaf, and root biomass. The LA did not differ among the treatments for three species and did not differ among species in full sun. The results for H:D ratio, DQI, and biomass indicate better growth in treatments with greater light availability. The species are recommended to be used as follows: Cedro-vermelha in full sun; Tarumã-azeitona, Ingá-doce, and Ocotea-guaicá in varying environmental conditions; and Branquilho-bravo in 50% shade and full sun conditions.
Diallec analysis in assessing the potential of Pinus elliottii x Pinus caribaea hybrids to develop populations for genetic improvement Scientia Forestalis Forest Sciences, 2018
