Genetic variability of Tachigali vulgaris trees based on seed morphophysiological traits

Abstract

Tachigali vulgaris is a tree with high potential for energy purposes in Brazil. However, there is little information about genetic variability that can be applied to plant breeding. Here, we quantified genetic variability based on biometric and emergence traits of T. vulgaris seeds from the native population of the Brazilian Amazon. The biometric aspects, moisture content, emergence, emergence speed index, and average emergence time of the seeds were evaluated. Genotypic values and genetic parameters were analysed using the mixed model methodology in a completely randomised design with 12 genotypes and four replications of 25 seeds. All biometric and emergence traits of seeds showed phenotypic and genetic variabilities. Heritability was high for all traits evaluated (0.66 to 0.97), and genetic accuracy showed high experimental precision and reliable results (≥ 0.90). Grouping by the Tocher, unweighted pair group with arithmetic mean and principal component analysis methods based on genetic traits returned four groups: Group 1 by Genotypes 1, 4, 5, 6, 7, 8, 9, 10 and 12; Group 2 by Genotype 3; Group 3 by Genotype 2; and Group 4 by Genotype 11. In addition, Genotypes 1, 3–10 and 12 displayed seeds with superior physical and physiological traits and a high probability of genetic gain. Our findings can be used in the selection and marking of trees with a broad genetic base for seed production and plant breeding of this species.