Realized Genetic Gain for 2nd-Year Height in Jack Pine

1989

S. 707-714

6 Abb., 3 Tab., 30 Lit. Ang.

Unselbständiges Werk

200088255

A complete cycle of within-family selection for 2nd-year height in jack pine (Pinus banksiana Lamb) was accomplished. The expected absolute gain from a theoretical population is 9.3%. The expected gain calculated using actual selected parental group means was 6.5% for upper selection and -6.5% for lower selection. Realized gains were 5.1% for upper selection and -3.7% for lower selection. Reasons for reductions in the realized gain compared with expected gain include (i) a finite base population size, (ii) biological constraints such as inconsistent seed production, (iii) non-normal distribution for the trait of interest, and (iv) nonselected male parents in open pollination.