Genetic analysis and elite tree selection of the main resin components of slash pine

Pine resin, as a natural material, has been widely used in food, pharmaceutical, and chemical industries. Slash pine (Pinus elliottii Engelm var. elliottii) is the primary tree species for resin tapping due to its high resin yield, low resin crystallization rate, and high turpentine content. Current researches focuse on the targeted improvement of several significant components to meet industrial needs rather than just resin yield. The objective of this study was to examine the genetic variation and correlation of genetic and phenotype for four main resin components (alpha pinene, beta pinene, abietic acid, and levoprimaric acid) of 219 half-sib progenies from 59 families. The results showed that the levopimaric acid had the largest content (mean value = 21.63%), while the beta pinene content had the largest variation coefficient (CV = 0.42). The alpha pinene content has the highest heritability (h(2) = 0.67), while levopimaric acid has the lowest heritability (h(2) = 0.51). There was a significant negative correlation between alpha pinene and the other three components and a significant positive correlation between beta pinene and the two diterpenes. The family ranking and genetic gain suggested that it is possible to improve the contents of main resin components of slash pine through genetic breeding selection.