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Apuleia leiocarpa Vogel J. F. Macbr. é uma espécie arbórea nativa do Brasil que possui madeira de alta qualidade e, atualmente, se encontra ameaçada de extinção. Mudas seminais de grápia dificilmente são comercializadas, sendo técnicas de propagação vegetativa, a exemplo da micropropagação, uma alternativa a ser considerada para produção de mudas. No entanto, há uma falta de informação disponível sobre a introdução in vitro de segmentos nodais e pouca informação está disponível sobre o enraizamento adventício de grápia. Como tal, existem lacunas de conhecimento que precisam ser abordadas para definir um protocolo de micropropagação para essa espécie. Assim, o objetivo deste estudo foi avaliar diferentes soluções de desinfestação na introdução de segmentos nodais e de diferentes tipos e concentrações de auxinas no enraizamento in vitro de explantes de grápia. Para a introdução, foram testados diferentes tipos de solução de desinfestação e tempos de imersão. Para o enraizamento, foram avaliadas diferentes concentrações e tipo de auxina. O melhor tratamento de desinfestação foi a imersão em solução de hipoclorito de sódio (NaOCl) a 2,5% de cloro ativo por 5 minutos. Para o enraizamento, o tratamento com 1,0 mg L-1 de ácido naftalenoacético (ANA, C10H7CH2CO2H) resultou nas maiores taxas enraizamento adventício. Os segmentos nodais de grápia podem ser estabelecidos in vitro, consistindo em boa fonte de propágulos para a micropropagação, e o enraizamento pode ser favorecido pela aplicação de ANA.

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.

As the energizing and therapeutic effects of infusions of mate (Ilex paraguariensis A.St.-Hil) leaves are increasingly recognized, rising global consumption is also increasing the demand for plantlets with high genetic and morphological qualities. Mini-cuttings are an alternative for clonal plantlets; however, more details are needed on factors that affect the success of this technique. Here, toward maximizing production, we evaluated adventitious rooting competence of mini-cuttings of different sizes and the morphophysiological quality of the resultant plantlets. Small (one bud; length up to 2.5 cm), medium (multiple buds; length 2.6–5.0 cm), and large (multiple buds; length 5.1–10.0 cm) mini-cuttings were planted in a mixture of commercial substrate, vermiculite, and coarse sand (1:1:1 v:v:v), grown in a humidity chamber, then evaluated after 45, 60, 75, and 90 days for survival, percentage of callus and shoot formation, number and length of shoots, percentage of rooted cuttings, and number and length of roots. Any rooted mini-cuttings were then cultivated in commercial substrate and subsurface soil (2:1 v:v) and evaluated after 30, 60, 90 and 120 days of cultivation for morphophysiology of the plantlets, percentage of survival, number of leaves, shoot height, stem diameter, and ratio of shoot height to stem diameter. After 120 days, the plantlets were evaluated for the ratio of shoot and root dry mass, total length, surface area, total volume, and mean diameter of roots and Dickson quality index. Adventitious rooting of the mini-cuttings and the morphophysiological quality of the plantlets were not influenced by the size of the vegetative propagule. Therefore, single-bud mini-cuttings have similar adventitious rooting competence, and result in plantlets with adequate morphophysiological quality, based upon leaf development, shoot height, stem diameter and length, and surface area, volume and diameter of roots. Single-bud mini-cuttings up to 2.5 cm long can thus be used to maximize production of mate plantlets by mini-cuttings.

O objetivo deste trabalho foi avaliar o efeito de épocas do ano e de clones na produtividade das minicepas e no enraizamento de miniestacas de erva-mate (Ilex paraguariensis A. St. - Hil.) tratadas ou não com ácido indolbutírico (AIB). Com esta finalidade, nas quatro épocas do ano realizou-se a coleta de brotos das minicepas de quatro clones de erva-mate, sendo que em cada coleta foi avaliada a porcentagem de sobrevivência das minicepas e o número de miniestacas. Posteriormente, os brotos foram seccionados em miniestacas de gema única, as quais foram ou não tratadas com 2000 mg L-1 de AIB. Aos 30 e 60 dias foram avaliadas as porcentagens de sobrevivência, enraizamento e calogênese, número e comprimento das raízes. As minicepas dos quatro clones de erva-mate apresentaram alta sobrevivência, além de produção constante de miniestacas dos clones 06SM17, 06SM12 e 06SM15 durante as quatro épocas do ano. O tratamento com AIB não incrementou no enraizamento das miniestacas de erva-mate. O processo rizogênico das miniestacas variou conforme o genótipo e a sazonalidade. O clone 06SM15 apresentou a maior capacidade rizogênica nas quatro épocas do ano. As melhores porcentagens de enraizamento foram verificadas nas épocas do outono e/ou inverno para os quatro genótipos avaliados.

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.

Leaves of mate is one of the main non-timber forest products marketed in South America, which makes establishment of new plantations of great interest. However, vegetative propagation of mate plantlets presents difficulties, which may be associated with the complexity of adventitious root formation. The aims of this study were to anatomically characterize the adventitious roots of mate-clone mini-cuttings and investigate the relationship of phenols and starch with adventitious rooting competence in mini-cuttings treated or not with indole-butyric acid (IBA). The mini-cuttings of four clones were collected at 0, 30, and 60 days of cultivation, fixed in a solution containing 1% glutaraldehyde and 4% formaldehyde, pre-infiltrated and infiltrated in (2-hydroxyethyl) methacrylate, and sectioned in a microtome. Ferric chloride and toluidine blue were used to detect phenolic compounds and lugol to identify starch. Adventitious roots formed in mini-cuttings treated with IBA presented disorganized xylem and phloem and poles irregularly but exhibited sclerenchyma vessel elements and tracheid cells indicating functionality. Differences in the rhizogenic ability of mate clones mini-cuttings were not due to the presence of anatomical barriers or the accumulation of phenolic compounds but be associated with the presence and distribution of starch grains in vegetative propagules.

Seedling production of canjerana (Cabralea canjerana (Vell.) Martius) has been limited by difficulty in germination, caused by recalcitrant behavior of their seeds. The objective of this study was to develop an efficient protocol for conservation and production of canjerana micropropagated plantlets. Seeds of canjerana were disinfected with 0, 2.5, 5.0, 7.5 and 10% of NaOCl solution, at immersion times of 10, 20 and 30 min to produce aseptic seedlings, which were cultivated on Murashige and Skoog (MS) and Woody Plant Medium (WPM) media. Nodal segments were cultivated in WPM medium supplemented with 0 and 2.5 µM of 6-benzylamine purine (BAP), kinetin (KIN) and thidiazuron (TDZ) or with 0, 1, 3, 6, 9 and 12 µM of BAP. Micro-cuttings were cultivated in MS and WPM media with 0 and 5.0 µM of indole-3-butyric acid (IBA) and naphthaleneacetic acid (NAA). The rooted micro-cuttings were acclimatized in a humid chamber in a greenhouse. The highest percentage of aseptic seedlings was produced with a solution of 7.5% of NaOCl and immersion times of 20 and 30 min. Adding BAP, KIN and TDZ or increasing concentrations of BAP to the WPM medium did not increase shoot number and length. Neither the base medium nor the auxin (IBA and NAA) had a significant effect on the survival of micro-cuttings after 60 days of cultivation, but the addition of 5.0 µM of NAA did increase the percentage of rooting and survival during the acclimatization. Both nodal segments and micro-stumps of canjerana have showed a low rate of multiplication. The addition of 5.0 µM of NAA to the basal medium increased the percentage of in vitro rooting and the percentage of survival during acclimatization of canjerana plantlets. Key words: In vitro propagation, in vitro multiplication, in vitro rooting, acclimatization, microclonal hedge.

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.

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. The aim of this study was to evaluate the in vitro establishment and growth of apuleia (Apuleia leiocarpa (Vogel) J. F. Macbr.) seedlings under different culture conditions. Apuleia seeds were treated with sulfuric acid (H2SO4) for 20min and disinfected by the immersion in 70% of ethanol for 30s and sodium hypochlorite with 0, 2.5 and 5.0% of active chlorine for 5, 10 and 15min. The percentage of disinfection and germination were evaluated at 30 days. Aseptic seedlings were transferred to WPM, MS and ½ MS culture medium and evaluated for shoot and root (cm) growth and number of nodal segments and leaves at 15 days. Apuleia seeds were also sown in WPM medium supplemented with 4, 5 or 6g L-1 of agar combined with 10, 20 or 30g L-1 of sucrose. The cultures were kept under two luminescence conditions: light throughout the establishment period and dark during the first seven days. The percentage of germination, shoot and root (cm) growth and number of nodal segments and leaves were evaluated at 15 days. In conclusion, the sulfuric acid and ethanol treatments were enough for the in vitro production of apuleia aseptic seedlings. The aseptic seedlings can grow in both WPM and MS medium, supplemented with 10g L-1 of sucrose and 4g L-1 of agar.