Selection between and within half-sibling progenies of Ilex paraguariensis for adventitious rooting of mini-cuttings

This study aimed to evaluate half-sibling progenies for developing breeding strategies and to select mate clones with adventitious root competence, required for vegetative propagation by mini-cuttings. For rooting, single-bud mini-cuttings of 2 cm length were treated with indolebutyric acid at 2000 mg L-1. At 60 days of cultivation, the mini-cuttings were evaluated for percentages of survival and rooting, number and mean length of the three largest roots, and number of rooted mini-cuttings per mini-stump. These data were analyzed considering the mixed model described for a completely randomized design, an environment, half-sibling progenies, and a single plant per plot, by using the SELEGEN-REML/BLUP software. The 50 genotypes with the highest number of rooted mini-cuttings were selected. The genetic gain was 48.41% for the number of rooted mini-cuttings per mini-stump. Selection for adventitious rooting based on the number of rooted mini-cuttings can be used in mate breeding programs for vegetative propagation by mini-cuttings.