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Mate (Ilex paraguariensis A. St.-Hil) is an arboreal species of great economic and socio-environmental importance, which presents difficulties in the adventitious rooting process. The rhizogenic competence of vegetative propagules of mate can be attained by coppicing, but the factors that influence the success of this technique have not yet been elucidated. Therefore, the aim of this study was to evaluate the effects of the stock plant, time of shoot collection, treatment with indolebutyric acid (IBA) and diameter of vegetative propagules in the adventitious rooting of cuttings from shoots induced by coppicing of selected adult plants of mate. Shoots produced from coppiced 13SM01 and 13SM05 stock plants were collected at different times of the year to prepare single-bud cuttings. The cuttings were measured as their diameter in the central portion and treated with 0 and 3000 mg L-1 of IBA. After 60 days, cuttings were evaluated to determine survival and rooting percentages, number of roots, and length of the three largest roots. A completely randomized design was used in a 4 × 2 × 2 × 13 (collection times x stock plants x IBA treatment x diameter classes) factorial scheme with 15 replications. Competence for adventitious rooting was highest for stock plant 13SM05. Cuttings collected in November and February had the highest rooting percentages, without the need of IBA treatment. Cuttings from 13SM01 and 13SM05 with diameters smaller than 0.636 cm (classes 1 to 6) and smaller than 0.712 cm (classes 1 to 7), respectively, had the highest rooting percentages and differed significantly from cuttings with larger diameters. Thus, the results of the present study indicate that stock plants, time of shoot collection, and diameter of vegetative propagules influence adventitious rooting competence of mate cuttings from coppicing adult plants. Rooting of mate cuttings with lower rhizogenic competence is influenced by the application of 3000 mg L-1 of IBA.

The aim of this work was to evaluate the in vitro productivity of grapia (Apuleia leiocarpa) micro-stumps cultivated in different media conditions to maximize its multiplication rate. Micro-stumps from aseptic seedlings were cultivated in WPM medium added with 0, 2.2, 4.4, 6.6 and 8.8 µM of 6-benzylaminopurine (BAP) and subcultured in WPM medium without cytokinin. Micro-stumps were also cultivated in WPM, MS or ½ MS base media with or without the addition of 1.5 g L-1 of activated charcoal and submitted to drastic pruning at 30, 60 and 90 days of cultivation. The in vitro cultivation of grapia micro-stumps in WPM or ½ MS media added with 8.8 µM of BAP and the subcultivation in media without cytokinin increase the number and length of shoots. The cultivation of grapia micro-stumps in media with activated charcoal increases the productivity of micro-cuttings per micro-stumps, but in the absence of activated charcoal induces callus formation and indirect organogenesis of shoots. The in vitro conservation of grapia microstumps maximizes the multiplication rate, being a feasible technique for the production of grapia plantlets.

The objective of this study was to evaluate the morphophysiological quality of yerba mate plantlets (Ilex paraguariensis A. St.-Hil.) produced by mini-cutting at four different times of year and cultivated in different containers. For the rooting of mini-cuttings, shoots of four yerba mate clones were collected four times during the year (April, July and October 2014 and January, 2015), cut into single-budded mini-cuttings and planted in equal proportions of pine bark-based commercial substrate, vermiculite and coarse sand. After 60 days of cultivation in a wet chamber, the rooted mini-cuttings were transferred to different containers: a 100 cm³ rigid polyethylene tube container and 500, 1500 and 3000 cm3 polyethylene bags containing pine bark-based commercial substrate and underground soil (2:1 v/v). A completely randomized design was used in a 4 x 4 factorial scheme, with five replications ranging from 5 to 20 mini-cuttings per experimental unit. The plantlets were evaluated for survival percentage, shoot height, stem diameter, shoot height/stem diameter ratio and number of leaves at 30, 60, 90 and 120 days of cultivation. At 120 days of cultivation, 10 plantlets from each treatment were randomly picked to evaluate shoot and root dry mass, Dickson quality index, shoot height, surface area, total volume and number of root tips. The best combinations of shoot height, length, surface area, total volume and number of root tips and Dickson quality index were found in plantlets produced in July, 2014, followed by plantlets produced in October,2014 and January, 2015. The polyethylene bags allowed the production of yerba mate plantlets with satisfactory quality of shoot and roots, regardless of the volume. Yerba mate plantlets can be produced by mini-cutting from July to January in polyethylene bags.

ABSTRACT: This study aimed to evaluate the rooting capability of apical and nodal mini-cuttings of ipe-roxo ( Handroanthus heptaphyllus ) in different substrates. Shoots produced from mini-stumps were fractioned into mini-cuttings 2-cm long apical or nodal mini-cuttings and treated with 1000 mg L-1 of indolebutyric acid (IBA). Four substrate combinations were evaluated: commercial substrate composed of pine bark and vermiculite in proportions of 1:1, 2:1 and 1:2 (v /v) and commercial substrate, vermiculite and sand in the proportion of 1:1:1 (v/v). The factorial experiment utilized a completely random design, with five replicates of four mini-cuttings. Rooting, shooting and survival percentage, number and length of shoots and roots were evaluated at 60 and 90 days of growth. Commercial substrate and vermiculite are a good combination for rooting mini-cuttings of ipe-roxo. Apical and nodal mini-cuttings exhibit similar rooting behavior and both are feasible for production of ipe- roxo plantlets.

O objetivo deste trabalho foi avaliar o estabelecimento e crescimento in vitro de plantas de grápia (Apuleia leiocarpa (Vogel) J. F. Macbr.) em diferentes condições de cultivo. Sementes de grápia tratadas com ácido sulfúrico (H2SO4) por 20min foram imersas em etanol a 70% por 30s e em hipoclorito de sódio (0; 2,5 ou 5,0% de cloro ativo) por 5, 10 ou 15min. Aos 30 dias de cultivo, as sementes foram avaliadas quanto às porcentagens de desinfestação e germinação. As plantas assépticas foram transferidas para os meios de cultura WPM, MS e ½MS e avaliadas quanto ao comprimento (cm) da parte aérea e total das raízes e ao número de segmentos nodais e folhas aos 15 dias. Sementes de grápia também foram semeadas em meio de cultura WPM, suplementado com 4, 5 ou 6g L-1 de agar combinado com 10, 20 ou 30g L-1 de sacarose, e mantidos sob duas condições de luminosidade: luz durante todo o período de estabelecimento e escuro durante sete dias após a semeadura. Foram avaliados a porcentagem de germinação das sementes, o comprimento (cm) da parte aérea e total das raízes e o número de segmentos nodais e folhas aos 15 dias. Concluiu-se que os tratamentos com ácido sulfúrico e etanol foram suficientes para o estabelecimento in vitro de plantas assépticas de grápia. Plantas assépticas podem ser cultivadas em meio de cultura WPM ou MS, suplementados com 10g L-1 de sacarose e 4g L-1 de agar.

This study aimed to evaluate the production of cordia (Cordia trichotoma) ministumps of seminal and asexual origin, as well as the effect of the naphthaleneacetic acid (NAA) on the rooting of mini-cutitings. Seedlings and plantlets from rooted cuttings were pruned to form a clonal mini-hedge. The ministumps were fertirrigated with three concentrations of nutrient solution and they were evaluated for survival and production of mini-cuttings. The mini-cuttings were or not treated with 1000mg L-1 of NAA and planted in substrate for rooting. The mini-cuttings were evaluated for the percentages of survival and rooting, and number and total length of roots after 30 days of cultivation. There was no difference in survival and number of mini-cuttings obtained from seminal or asexual ministumps. Mini-cuttings from ministumps of asexual origin showed higher rooting capability. The use of 1000mg L-1 NAA did not increase the rooting percentage of cordia mini-cuttings.