Enraizamento de miniestacas em diferentes épocas de coleta para a seleção de clones de canjerana

Abstract

RESUMO:O objetivo deste trabalho foi estudar o efeito de época de coleta no enraizamento de miniestacas para desenvolver uma estratégia de seleção que maximize o ganho genético e facilite a identificação de clones de canjerana com potencial para a propagação vegetativa. Um minijardim clonal foi estabelecido com 22 clones de canjerana, no qual realizaram-se coletas de miniestacas em três épocas durante o período de maior crescimento vegetativo. Foram avaliadas as percentagens de sobrevivência, enraizamento e brotação de miniestacas, o número e comprimento de raízes e brotos e o número de miniestacas enraizadas por minicepa. Os clones foram agrupados pelo método não-hierárquico das k-médias para o número de miniestacas enraizadas em cada época de coleta. A identificação dos melhores clones foi realizada com base na soma de postos e estimado o ganho genético de seleção. A época de coleta das brotações afeta o enraizamento de miniestacas de canjerana. A seleção de clones de canjerana deve ser realizada com base no número de miniestacas enraizadas por minicepa durante todo o período de crescimento vegetativo.Palavras-chave: Cabralea canjerana; ganho genético; miniestaquia; sazonalidade Rooting of mini-cuttings in different collection times for the selection of canjerana clonesABSTRACT: The objective of this work was to study the effect of the collection time in rooting capability of mini-cuttings to develop a selection strategy to maximize genetic gain from selection and to facilitate the identification of canjerana clones with potential for vegetative propagation. A clonal mini-hedge was established with 22 canjerana clones and mini-cuttings were collected in three different times during the vegetative growth season. The percentages of survival, rooting and shooting, the number and length of roots and shoots and the number of rooted mini-cuttings per mini-stump were evaluated. The clones were clustered by the nonhierarchical k-means method for the number of rooted mini-cuttings in each collection time. Clone selection was based upon the sum of ranks and genetic gain from selection was estimated. The collection time of canjerana shoots affects the rooting capability of mini-cuttings. Selection of canjerana clones should be based upon the number of rooted mini-cuttings per mini-stump, during the whole season of vegetative growth.

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

“…As expected, one of the highest values of Acgen was obtained for the number of rooted mini-cuttings (Table 2), also indicating that the selection for rooting competence of mini-cuttings should be performed based on this trait. These results are in agreement with those of Burin et al (2018), who performed the selection of C. canjerana clones based on the number of rooted mini-cuttings over three successive collections, highlighting the feasibility of using this trait to identify genotypes with high competence for adventitious rooting of mini-cuttings.…”

“…Considering the linear correlation among evaluated traits, the number of rooted mini-cuttings per mini-stump can be used to identify mate genotypes with high adventitious rooting competence within and between half-sibling progenies, which would facilitate and simplify the selection process of superior clones for vegetative propagation by mini-cuttings. These results are in agreement with those observed in C. canjerana, suggesting that the selection of clones should be performed based on the number of rooted mini-cuttings during the period of vegetative growth (Burin et al 2018).…”

“…Since mini-cutting productivity is associated with adventitious rooting competence in mate half-sibling progenies, the greater the number of mini-cuttings rooted per mini-stump, the greater would be the percentage of rooting and the number and length of roots. Similar results have been reported in herbaceous mini-cuttings of Prunus persica (Timm et al 2015) and mini-cuttings of C. canjerana (Burin et al 2018), where high correlations were found between the number and length of roots. Considering the linear correlation among evaluated traits, the number of rooted mini-cuttings per mini-stump can be used to identify mate genotypes with high adventitious rooting competence within and between half-sibling progenies, which would facilitate and simplify the selection process of superior clones for vegetative propagation by mini-cuttings.…”

Production of jacaranda plantlets by minicutting

“…The jacaranda mini-clonal hedge was established in October 2015, with a total of 48 seedlings that were 120 days old after sowing ( Figure 1A). The plantlets were planted in four polyethylene trays (55 cm x 34 cm x 15 cm) with spacing of 10 cm x 10 cm and the mini-clonal hedge was established according to the methodology used for other forest species in the MPVP-UFSM, such as Cabralea canjerana (Vellozo) Martius (Burin, Bisognin, Lencina, & Gimenes, 2018a;Burin, Bisognin, Lencina, Somavilla, & Pedroso, 2018b;Gimenes et al, 2015), Ilex paraguariensis A. St.-Hil. (Pimentel, Lencina, Pedroso, Somavilla, & Bisognin, 2017) and Handroanthus heptaphyllus Vell.…”