Potato improvement for tropical conditions: II. Selection indices and efficiency of indirect selection

This study evaluated the efficiency of selection indices that can contribute to potato clone selection underfavorable and stressful conditions as well as the possibility of indirect selection for heat tolerance. Among the selectionindices, the arithmetic and geometric means and index 4 were the most appropriate. The susceptibility index and percentageof yield reduction indicate only specifically adapted clones. Indirect selection for heat tolerance is not suitable in view of thelow correlation coefficient among clone means in the environments. Selection based on the overall environment mean is morefit to select broadly adapted genotypes. In general, clones that performed best under stress conditions and presented heattolerance were specifically adapted, in spite of low performance means under favorable conditions. Well-adapted genotypes toboth stress and favorable conditions can however be selected