Genetic Variation and Selection of Growth Traits in Full-sib Families of Pinus elliottii

In order to analyse the variation pattern of growth traits of Pinus elliottii, the genetic progeny of 15 P. elliottii family of 6.5 years of age were used as materials to analyse the growth traits of diameter at breast height (DBH), tree height (H) and volume of timber (V), to reveal their genetic patterns, and to screen out the good family using Breggin's multi-trait evaluation method, and to screen out the good single plants using the V as the first index. The results showed that the growth traits of P. elliottii were excellent, and there was a highly significant difference between the family; the DBH was the most affected by the genetic effect, and the heritability of the family was obviously greater than that of the single plants; there was a highly significant correlation between the growth traits and the correlation coefficient of the V of a single plant and DBH was 0.94, which indicated that there was a strong positive correlation between the two; the use of the Breggin multiple traits comprehensive evaluation method screened out two excellent family. At the same time, using V as the first index, 12 excellent single plants were screened, and the realistic gain ranges of their DBH, H and V were 18.91%-63.88%, 3.61%-114.40% and 39.14%-211.35%, respectively, indicating a remarkable screening effect. In conclusion, the growth traits of P. elliottii are rich in genetic variation within the family, and have greater potential for selection and breeding. The 2 excellent family lines and 11 excellent single plants were obtained from this screening.