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In this study, we evaluated the adventitious rooting competence of mini-cuttings and plantlet growth of two clones of swamp cork (Erythrina crista-galli L.). Experiments were carried out in a factorial of two clones to study the need of application of indolebutyric acid (IBA), substrate composition for mini-cutting rooting and plantlet growth, and rooting curves of the clones 15SM05 and 15SM08, in the completely randomized design. Mini-cuttings of swamp cork clones showed high rooting competence, with mean rooting percentage above 80% even without IBA application. Vermiculite and its combination with commercial substrate resulted in the highest percentage of rooting, and number and length of roots and shoots. The clones showed differences regarding their adventitious rooting competence and the increment in rooted mini-cuttings with time in a humidity chamber, being the clone 15SM05 the most suitable for plantlet production.

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.

The objective of this study was to investigate the production of jacaranda (Jacaranda mimosifolia D. Don) plantlets by minicutting. For this, a mini-clonal hedge was established to supply sprouts for minicuttings. For adventitious rooting, the minicuttings were treated with hydroalcoholic solution of indolebutyric acid at concentrations of 0, 1000, and 2000 mg L-1 and grown in a greenhouse. The survival of minicuttings was evaluated at 30, 60, and 90 days, and rooting, callus, sprouting, leaf area, root area, aerial dry mass, root dry mass, total dry mass, and aerial/root dry mass ratio were assessed at 90 days. The rooted minicuttings were treated with different volumes of nutrient solution (0, 25, and 50 mL) and were evaluated for survival, height, diameter, leaf area, root area, aerial dry mass, root dry mass, and aerial/root dry mass ratio of the plantlets after 30 days of cultivation in a shade house and full sunlight. Jacaranda can be established in a mini-clonal hedge for the production of shoots necessary for the preparation of minicuttings. The minicuttings are rooted in a greenhouse without use of indolebutyric acid. The plantlets produced can be acclimatized in a shade house and rustified in full sun. Jacaranda plantlets can be produced by minicuttings.

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.

Cordia (Cordia trichotoma (Vell.) Arrab. ex Steud.) is a native species that has high quality wood and potential for the establishment of commercial plantations. However, its propagation by seeds is difficult, and vegetative propagation is a good alternative. The aim of this study was to evaluate the vegetative propagation of cordia by cuttings from shoots and roots. In one experiment, cuttings from shoots of adult plants were treated with 0 and 40 mM of indolbutyric acid (IBA). In other experiment, cuttings from roots of adult plants were classified by diameter as thick (2.0-3.0 cm) and thin (

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.

The objective of this work was to define an early selection strategy to identify Cabralea canjerana (Meliaceae) clones with high multiplication rate. A mini-garden of 109 clones of canjerana seedlings was established in a completely randomized design, in an acclimatized greenhouse. From seedlings, the mini-stumps and mini-cuttings were obtained. Mini-cuttings were collected at five different times, and the number of mini-cuttings per mini-stump, rooting percentage, and number of rooted mini-cuttings were quantified. The number of rooted mini-cuttings per mini-stump was the only trait that showed high correlation with the others. Five groups of clones based on the number of rooted mini-cuttings per mini-stump were separated using k-means clustering, and the genetic gain from selection and Pearson correlation were estimated. The selection of the two best groups in each evaluation period resulted in high genetic gains from selection for all evaluated traits. Early selection for the number of rooted mini-cuttings discarded 65% of the evaluated clones, which increases experimental precision in evaluations of traits associated with plantlet growth and quality. Early selection for the number of rooted mini-cuttings per mini-stump at different times allows the identification of Cabralea canjerana clones with high multiplication rate. Resumo: O objetivo deste trabalho foi definir uma estratégia de seleção precoce para identificar clones de Cabralea canjerana (Meliaceae) com alta taxa de multiplicação. Um minijardim com 109 clones de plântulas de canjerana foi estabelecido com um delineamento inteiramente casualizado em casa de vegetação climatizada. Das plântulas, foram obtidas as minicepas e as miniestacas. As miniestacas foram coletadas em cinco épocas, e foram quantificados o número total de miniestacas por minicepa, a percentagem de enraizamento e o número de miniestacas enraizadas. O número de miniestacas enraizadas por minicepa foi o único caráter que apresentou alta correlação com os demais. Foram estabelecidos cinco grupos de clones com base no número de miniestacas enraizadas por minicepas, pelo agrupamento das k-médias, e estimados o ganho genético de seleção e a correlação de Pearson. A seleção dos dois melhores grupos em cada época resultou em altos ganhos de seleção para os caracteres avaliados. A seleção precoce para o número de miniestacas enraizadas descartou 65% dos clones avaliados, o que aumenta a precisão experimental em avaliações de caracteres associados ao crescimento e à qualidade das mudas. A seleção precoce do número de miniestacas enraizadas por minicepas, em diferentes épocas, permite identificar clones de Cabralea canjerana com alta taxa de multiplicação.

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 non-hierarchical 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.

O objetivo deste trabalho foi avaliar a produtividade de microcepas de grápia (Apuleia leiocarpa) mantidas em diferentes condições de cultivo in vitro, visando maximizar a taxa de multiplicação. Microcepas oriundas da poda drástica de plantas assépticas foram cultivadas em meio de cultura WPM acrescida de 0; 2,2; 4,4; 6,6 e 8,8 µM de 6-benzilaminopurina (BAP) e subcultivadas em meio de cultura WPM sem citocinina. Microcepas de grápia também foram cultivadas em meio de cultura WPM, MS ou ½ MS, acrescido ou não de 1,5 g L-1 de carvão ativado e submetidas a três coletas de brotos aos 30, 60 e 90 dias de cultivo. A manutenção das microcepas em meio de cultura WPM ou ½ MS suplementado com 8,8 µM de BAP, seguido do subcultivo em meio de cultura sem citocinina aumenta o número e o crescimento de brotações. O cultivo de microcepas de grápia em meio de cultura com carvão ativado aumenta a produção de microestacas por microcepas, enquanto a ausência de carvão ativado favorece a formação de calos e brotos por organogênese indireta. A manutenção in vitro de microcepas de grápia maximiza a taxa de multiplicação, constituindo-se de uma técnica promissora para a produção de plantas de grápia.

In this study, we aimed to evaluate half-sibling progenies of Myrocarpus frondosus based on morphological characteristics and to select seedlings with high growth vigor and quality. Seedlings were evaluated for shoot height and diameter, shoot height/diameter ratio, and number of leaves. The shoot height showed the highest estimations of linear correlation with the other characteristics. The linear correlation of shoot height between two consecutive evaluations was high from 60 days of cultivation, indicating that selection should be applied after this period. Selection of 101 seedlings within the best progenies resulted in a genetic gain of 15.13% for shoot height. The greatest indirect gain from selection was for the shoot height/diameter ratio, whereas the lowest indirect gain was for the stem diameter. Myrocarpus frondosus progenies can be selected for shoot height at 60 days of nursery cultivation, resulting in high direct gain for growth and indirect gain for stem height/diameter ratio.

The competence of adult plants of mate (Ilex paraguariensis St. Hil.) to undergo adventitious rooting is essential to their vegetative rescue by cuttings. This study aimed to evaluate the adventitious rooting competence of adult mate plants, and then rescue these plants by making cuttings from epicormic shoots induced in different trunk positions. The percent survival and rooting of cuttings from epicormic shoots induced by girdling in seven adult plants were evaluated. The two stock plants whose cuttings had the highest rooting competence were further pruned and girdled to evaluate the effect of the position of epicormic shoots on their adventitious rooting competence. The potential success of rescuing of the same adult plants was also studied with cuttings of epicormic shoots induced by coppicing. The shoots were sectioned in single-bud cuttings, either treated with 3,000 mg L-1 indolebutyric acid or untreated, and then cultivated in a humid chamber for 60 days, and then the percent survival and rooting of cuttings was evaluated. In conclusion, we found that it is possible to rescue adult mate plants by cuttings from epicormic shoots induced by pruning, girdling, or coppicing. The adventitious rooting competence of cuttings differs among adult mate plants, and depends on the position of the epicormic shoots on the trunk from which epicormic shoots are collected.

The aim of this research was to evaluate the feasibility of rescuing adult plants by cuttings from post-fire epicormic shoots. We evaluated the native tree species erva mate ( Ilex paraguariensis St. Hil.) and canjerana ( Cabralea canjerana Vell. Mart.), which present difficult seedling production and are economically and ecologically important. The plant material used for the preparation of cuttings consisted of shoots from bud differentiation of tissue from the stem collar of the trees. One-bud cuttings of erva mate were treated with 4000 or 8000mg L-1 of indolebutiric acid (IBA) and the checks were not treated with auxins. The cuttings were grown in three different substrates: carbonized rice husks, vermiculite and coarse sand. The experiment was a factorial with a completely random design and five replicates of five cuttings. One-bud cuttings from the basal, intermediate and apical parts of canjerna shoots were treated with 0 or 6000mg L-1 of IBA and planted in commercial substrate and coarse sand (3:2 v/v). The experiment was a factorial with a completely random design and ten replicates of three cuttings. Cuttings from post-fire epicormic shoots can be used for rescuing erva mate and canjerana adult plants. Erva mate cuttings treated with 8000mgL-1 IBA have increased rooting when grown in coarse sand. Canjerana cuttings from the basal part of epicormic shoots have greater survival and rooting than those from intermediate and apical parts. RESUMO: O objetivo deste trabalho foi avaliar a possibilidade de resgatar árvores adultas por estaquia de brotos epicórmicos de rebrota pós-fogo. Foram estudadas a erva-mate ( Ilex paraguariensis St. Hil.) e a canjerana ( Cabralea canjerana Vell. Mart.), que são espécies nativas de difícil propagação por sementes e de relevante importância econômica e ecológica. O material vegetativo utilizado para o preparo das estacas foi constituído de brotos, provenientes da rebrota da diferenciação dos tecidos de gemas do colo de árvores matrizes com, aproximadamente, 20 anos de idade. Para a erva-mate, estacas de gema única foram tratadas com 4000 e 8000mg L-1 de ácido indolbutírico (IBA), e as testemunhas que não receberam tratamento auxínico. As estacas foram cultivadas em três diferentes substratos: casca de arroz carbonizada, vermiculita e areia de granulometria grossa. O experimento foi um fatorial no delineamento inteiramente casualizado, com cinco repetições de cinco estacas. Para canjerana, estacas basais, medianas e apicais de gema única, foram ou não tratadas com 6000mg L-1 de IBA e cultivadas em substrato comercial e areia de granulometria grossa (3:2 v/v). O experimento foi um fatorial no delineamento inteiramente casualizado, com dez repetições de três estacas. A estaquia de rebrota pós-fogo pode ser utilizada para o resgate de árvores adultas de erva-mate e canjerana. Estacas de erva-mate tratadas com 8000mg L-1 de IBA enraízam melhor em areia grossa. Estacas de canjerana, obtidas da porção basal das brotações, apresentam maior sobrevivência e enraizamento do que as medianas e apicais.

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. RESUMO: O objetivo deste estudo foi avaliar o enraizamento de miniestacas apicais e nodais de ipê-roxo ( Handroanthus heptaphyllus ) em diferentes substratos. Brotos coletados de minicepas foram seccionados em miniestacas de 2cm de comprimento, classificadas em apical ou nodal e tratadas com 1000mg L-1 de ácido indolbutírico (AIB). Foram também testadas as composições de substrato comercial à base de casca de pinus e vermiculita nas proporções de 1:1; 2:1 e 1:2 (v/v) e de substrato comercial, vermiculita e areia grossa (1:1:1 v/v). O experimento foi um fatorial no delineamento inteiramente casualizado, com cinco repetições de quatro miniestacas. A porcentagem de enraizamento, de brotação e de sobrevivência, o número e comprimento de brotos e raízes foram avaliados aos 60 e 90 dias. Miniestacas de ipê-roxo cultivadas em substrato comercial e vermiculita apresentam maior capacidade de enraizamento. Miniestacas apicais e nodais apresentam similar comportamento de enraizamento, podendo ambas serem utilizadas para a produção de mudas de ipê-roxo.

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.