PREDICTIONS OF AGE-AGE CORRELATIONS OF TOTAL HEIGHT BASED ON SERIAL CORRELATIONS BETWEEN HEIGHT INCREMENTS IN MARITIME PINE (PINUS-PINASTER AIT)

Successive annual height increments (AHIs) are considered to be elements of a time series. Empirical data in Maritime pine (Pinus pinaster Ait.) show that genetic correlations between successive AHIs (serial correlation) decrease when the lag between corresponding growing seasons increases. When separated by more than 13 years AHIs are no longer genetically correlated. It is shown that age-age correlations between total heights depend on three components: the serial correlation structure between AHIs, the genetic coefficient of variation of AHIs, and the phenotypic growth curve of AHIs. Age-age correlations are computed in various combinations of the three components. Serial correlation structure and the genetic coefficient of variation had the more pronounced effect on age-age correlations. The genetic correlation between height at age 10 and height at age 50 varies between 0.764 and -0.136 according to the different combinations. Results obtained by simulations are comparable to those issued from previous empirical methods. Implications on early selection procedures and on optimal selection age are discussed.