Abstract The objective of this research was to select orange-fleshed sweet potato clones with high stability, yield, and β-carotene content in different planting seasons, using a selection index. Joint analysis of experiments and analysis of responsiveness and stability by the GGE biplot method were performed for the variables yield, dry matter percentage, and root flesh color. The variables yield, dry matter, color and stability were used to estimate a selection index. The GGE biplot analysis indicated that there are differences among clones in stability for Yield. However, the percentage of dry matter and color of the roots show low interaction in the different environments. Because of that, stability for yield was included in the selection index, together with yield, dry matter, and root orange color intensity. Finally, the selection index based on stability, yield, dry matter percentage and root color was efficient in the selection of a new biofortified sweet potato cultivar. orangefleshed fleshed βcarotene β carotene seasons Yield However environments intensity Finally cultivar

ABSTRACT Tomato is one of the most important crops worldwide. Bacterial wilt (BW), caused by Ralstonia spp., is a major disease for tomato production around the world, especially in tropical and subtropical regions. Currently in Brazil, only commercial hybrids are available as resistant rootstocks for use in infested areas, and we lack information regarding resistance to aggressive strains. Thus, the aims of this work were to estimate combining abilities of five tomato inbred lines and hybrids and to identify resistant genotypes for using as rootstocks resistant to Ralstonia solanacearum biovar 2, phylotype II, one of the most aggressive strains in Brazil. Combining abilities for BW resistance were assessed through full diallel crossings among five tomato inbred lines without reciprocals. The experiment was carried out in a greenhouse, in a complete randomized blocks design, using 15 genotypes (hybrids and parents). Additive genetic effects showed to be the most important for controlling bacterial wilt. The inbred line Hawaii 7996 exhibited the highest general combining ability among the five parents assessed. The hybrid Hawaii 7996 × Rodade was the best crossing in terms of resistance and specific combining ability, which was greater than those of all other hybrids. Although Hawaii 7996 remains as a major source for BW resistance, further researches are needed to better understand the resistance dynamics, seeking to develop hybrids with transgressive segregations and more stable resistance against aggressive strains and thrive under environmental conditions highly favorable to bacterial wilt infection.