Factors affecting capsule and seed set in Eucalyptus globulus seed orchards

Low capsule seed set is a major factor limiting seed production in Eucalyptus globulus seed orchards. Trials were conducted in two Tasmanian E. globulus seed orchards to identify mechanisms involved in capsule abortion and low reproductive success. Key areas of investigation included identification of the timing of abortion relative to stage of capsule development, the impact of irrigation management and other treatments imposed to alter resource allocation, the influence of the maternal and paternal genotype, and relationship between floral characteristics and propensity of capsules to abort.