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techniques in I. paraguariensis mother trees and its cutting according to the material rejuvenation degree. CERNE, v. 24, n. 3, p. 240-248, 2018. HIGHLIGHTS Semi-girdling technique produces longer epicormic shoots in native Ilex paraguariensis. Cuttings form epicormic shoots produce a higher number of roots than treetop shoots. Shoots from detached live branches have short length with high number of leaf buds. New studies are needed regarding techniques to elongate shoots from detached branches.

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The rooting process of sequoia minicuttings presents clonal infl uence. The average rooting is over 85% in all seasons. The rooting of minicuttings occurs between 50 and 70 days. It is indicated the presence of 90 days of minicuttings in the rooting environment.

Ilex paraguariensis A. St. Hil. (yerba mate) is a native species widely consumed in southern Brazil, a region that presents a current scenario of forest fragmentation. The objective was to evaluate the genetic diversity, genetic structure, and gene flow among cohorts of I. paraguariensis in two forest remnants. Genetic analyses were conducted using microsatellite markers from leaves from adult (Ad), regenerating (Reg), and seed-derived (Se) populations in Santa Catarina (SC) (ChapecÃ’s National Forest [CCO]) and Rio Grande do Sul (RS) (Teixeira Soares’ Municipal Natural Park [PTS]). We found unique alleles in both populations, eleven in the CCO and eight in the PTS. There was no significant difference in genetic diversity indexes, whereas high and significant fixation indexes were observed (FCCO = 0.394; FPTS = 0.319). The proportion of genetic variation obtained between populations was lower (8%) than the proportion within populations (92%). The presence of significant genetic structure was verified in the cohorts of I. paraguariensis for two study areas. Moreover, all pairwise genetic divergence between Ad and Reg, and Ad and Se cohorts was significant, except for Ad versus Reg in PTS. Aiming to maintain diversity over generations, we recommend the conservation of remnants and expansion of connectivity between fragments. Study Implications Ilex paraguariensis is a species of high consumption and of social, cultural, and economic importance in southern Brazil. It occurs naturally or was naturalized in highly fragmented forests, which may reduce genetic diversity. The genetic analyses of different cohorts of I. paraguariensis reveals the current status of the genetic diversity of the species and indicates how diversity is maintained over generations. Thus, the study provides information for its use and conservation, maintaining genetic diversity.