Breeding objectives were defined for pulp production of Eucalyptusglobulus Labill, using a simple profit equation relating the monetary cost savings per tonne of pulp produced with stem volume, wood density, and pulp yield. The economic importance of each trait was calculated for five different pulp and forestry industry scenarios with widely different cost structures. Selection indices integrating various combinations of volume growth, wood density, and pulp yield were compared for their ability to meet the different breeding objectives. There was surprising consistency in results across the range of breeding objectives and cost structures studied. It was clear that selection indices integrating volume, wood density, and pulp yield gave the most accurate selection and maximized genetic gain in breeding objectives. The cost savings from indices that included only volume were always much less than one-half, and sometimes as low as one-quarter, as much as those from indices integrating volume and wood traits. In the case study considered, E. globulus in Portugal, these cost savings had substantial implications for company profitability.

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Theory is given for a simple practical method of predicting gain from two-stage independent culling, where stage 1 of selection is for individual performance and stage 2 is for either progeny performance only, or an index combining individual and progeny performance. Expected gain is determined as a direct function of heritabilities, genetic correlations, selection intensities and progeny-testing capacity. Results show the effect these parameters can have on proportions selected at each stage and, if multiple selection criteria are used, traits selected for first. Methods are discussed in the context of tree and animal breeding, with an example taken from forestry.

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