Effect of genotype on in vitro adventitious shoot formation in Pinus radiata and correlations between pairs of phenotypic traits during in vitro shoot development

The influence of genotype at the family and clone levels on adventitious shoot formation in Pinus radiata was examined using the cotyledon tissue culture system. Twenty-nine full-sib and two selfed families were used. Family and clone influenced all in vitro traits assessed and final adventitious shoot formation significantly. Five families selected for the long-internode trait and two selfed families used in the study were of average performance when compared to all families. Correlations using family means or clone-within-family means showed that shoot production could be predicted based on measures of early culture health. Shoot production after 16 weeks was positively related to early embryo (6 days) and early culture (4 weeks) health. Shoot production could be improved by approximately 100% through family selection, but only limited additional improvements were obtained through early embryo selection.