Identical and non-identical seedling twins in Pinus radiata

Abstract

Thirteen sets of twin seedlings emerging from single seeds of Pinus radiata were raised. Using morphology in 2 cases and oleoresin analysis in the remaining 11, six sets were accepted as genetically identical, one probably identical, two probably non-identical, and four definitely non-identical. Therefore, twins apparently result from both cleavage and archegonial polyembryony.