Jasmonic and Salicylic Acids Enhance Biomass, Total Phenolic Content, and Antioxidant Activity of Adventitious Roots of Acmella radicans (Jacq.) R.K. Jansen Cultured in Shake Flasks.

Acmella radicans (Asteraceae) is a plant native to America. Despite it having medicinal attributes, studies on its phytochemical properties are scarce, and biotechnological studies do not exist for this species. In this study, we established an adventitious root culture from A. radicans internodal segments in shake flasks with indole-3-butyric acid (IBA), and then elicited it with jasmonic acid (JA) and salicylic acid (SA). The total phenolic content and antioxidant activity were evaluated, and a comparison was made using in vitro plantlets and wild plants. Internodal segments with 0.1 mg/L IBA showed 100% root induction and exhibited better growth after transfer to shake flasks with MS liquid culture medium. JA had a significant effect on biomass increase compared to unelicited roots, mainly with 50 µM JA (28%), while SA did not show significant results. Root elicited with 100 µM (SA and JA) showed a 0.34- and 3.9-fold increase, respectively, in total phenolic content (TPC) compared to the control. The antioxidant activity was also significant, and a lower half-maximal inhibitory concentration (IC50) was observed as the AJ concentration increased. Roots elicited with AJ (100 µM) exhibited high antioxidant activity with DPPH (IC50 = 9.4 µg/mL) and ABTS (IC50 = 3.3 µg/mL) assays; these values were close to those for vitamin C (IC50 = 2.0 µg/mL). The TPC and antioxidant activity of in vitro plants and root cultured in shake flasks showed the lowest values in most cases; even the root cultures without elicitation were better than those of a wild plant. In this study, we demonstrated that A. radicans root culture is capable of producing secondary metabolites, while its production and antioxidant activity can be enhanced using jasmonic acid.

Morphology, germination, and geographic distribution of Pentaclethra macroloba (Fabaceae): a hyperdominant Amazonian tree / Morfología, germinación y distribución geográfica de Pentaclethra macroloba (Fabaceae): árbol amazónico hiperdominante

Introduction: Pentaclethra macroloba is a hyperdominant tree in the Amazon estuary of great socioeconomic importance for the region because the oil from its seeds is a powerful herbal medicine. Objective: We aimed to characterize the morphological structure, the morphological adaptations in response to the daily flooding of the Amazon estuary and the biogeographic area of P. macroloba. Methods: Detailed description of the external morphology, from germination to the adult tree, was obtained from individuals located in floodplain forest, Northeast Amazonia. The occupation area and the geographical extension of P. macroloba were determined from point of geographical coordinates of botanical samples deposited in the digital collections of Mobot and SpeciesLink. Results: Adult individuals have adapted structures in response to daily flooding, such as: adventitious roots to increase respiratory efficiency and lenticels in the trunk, serving as a connection point for oxygen transport between the root and the aerial part. Dried fruit favours the activation of the explosive dehiscence mechanism, allowing the seed to be expelled long distance. Deltoid shape of the seed allows water fluctuation and more efficient dispersal. Seedling is phanerocotylar hypogeal and with one pair of reserve cotyledons that provide the seedling an extra source of energy to escape the flood. Germination rate was 78 % and the speed was 0.2 seeds.day-1. Circular buffer method revealed the presence of 123 subpopulations of P. macroloba distributed in a radius of 5 699 943 km² across the Neotropical region. Conclusions: Much of the morphological structures of P. macroloba are adaptive and evolutionary responses to the periodically flooded environment of the Amazon estuary, showing that these environments select the trees, best adapted, to inhabit the flood. P. macroloba has a wide geographical area denotes the plasticity of adapting to different environments, which may justify its monodominance in some regions.

Introducción: Pentaclethra macroloba es un árbol hiperdominante en el estuario del Amazonas, de gran importancia socioeconómica para la región, pues el aceite de sus semillas es un poderoso medicamento natural. Objetivo: Nuestro objetivo fue caracterizar la estructura morfológica, las adaptaciones morfológicas en respuesta a las inundaciones diarias del estuario del Amazonas y el área biogeográfica de P. macroloba. Métodos: Una descripción detallada de la morfología externa, desde la germinación hasta el árbol adulto, se obtuvo de individuos ubicados en el bosque periódicamente inundado, al noreste de la Amazonia. El área de ocupación y la extensión geográfica de P. macroloba se determinaron a partir del punto de coordenadas geográficas de muestras botánicas depositadas en las colecciones digitales de Mobot y SpeciesLink. Resultados: Los individuos adultos tienen estructuras adaptadas en respuesta a las inundaciones diarias, tales como: raíces adventicias para aumentar la eficiencia respiratoria y lenticelas en el tronco, que sirven como punto de conexión para el transporte de oxígeno entre la raíz y la parte aérea. Los frutos secos favorecen la activación del mecanismo de dehiscencia explosiva, permitiendo que la semilla sea expulsada a larga distancia. La forma deltoidea de la semilla permite la fluctuación en el agua y una dispersión más eficiente. La plántula es hipogel fanerocotiledones y con un par de cotiledones de reserva que proporcionan a la plántula una fuente extra de energía para escapar de la inundación. La tasa de germinación fue del 78 % y la velocidad fue de 0.2 semillas día-1. El método Circular buffer reveló la presencia de 123 subpoblaciones de P. macroloba distribuidas en un radio de 5 699 943 km² a lo largo de la región neotropical. Conclusiones: Gran parte de las estructuras morfológicas de P. macroloba son respuestas adaptativas y evolutivas al ambiente periódicamente inundado del estuario del Amazonas, lo que demuestra que estos ambientes actúan como filtro ambiental seleccionado las especies mejor adaptadas al medio. Su amplia área geográfica denota la plasticidad de adaptarse a diferentes ambientes, lo que puede justificar su monodominancia en algunas regiones.

The role of auxin transporters and receptors in adventitious rooting of Arabidopsis thaliana pre-etiolated flooded seedlings.

Adventitious roots (ARs) form from above-ground organs, and auxins are major regulators of AR development. TIR1/AFB F-box proteins act as well-established auxin receptors. Auxin transport involves the PINFORMED (PIN) auxin efflux carriers and AUXIN RESISTANT 1/LIKE AUX1 (AUX1/LAX1) influx carriers. To further elucidate the basis of AR development, we investigated the participation of these proteins and phosphorylation of PINs during adventitious rooting in hypocotyls of pre-etiolated flooded Arabidopsis thaliana seedlings. Mutant and GUS localization studies indicated that AFB2 is important in AR development. AUX1 loss-of-function reduced AR numbers, which could not be reversed by exogenous auxin. Single mutations in LAX1, LAX2 and LAX3 had no negative impact on AR development and the first and last mutations even promoted it. Double and triple mutants of AUX1, LAX1, LAX2 and LAX3 significantly reduced rooting, which was reversed by exogenous auxin. AUX1 was essential in AR establishment, with LAX3 apparently acting in conjunction. Proper phosphorylation of PINs by PID, WAG1 and WAG2 and auxin transport direction were equally essential for AR establishment. PIN1, AUX1 and AFB2 (overexpression) and LAX1, LAX3, PIN4 and PIN7 (downregulation) emerged as potential targets for genetic manipulation aiming at improving AR development.

Microbial transformation of ginsenosides extracted from Panax ginseng adventitious roots in an airlift bioreactor

Background: Ginsenoside is the most important secondary metabolite in ginseng. Natural sources of wild ginseng have been overexploited. Although root culture can reduce the length of the growth cycle of ginseng, the number of species of ginsenosides is reduced and their contents are lower in the adventitious roots of ginseng than in the roots of ginseng cultivated in the field. Results: In this study, 147 strains of ß-glucosidase-producing microorganisms were isolated from soil. Of these, strain K35 showed excellent activity for converting major ginsenosides into rare ginsenosides, and a NCBI BLAST of its 16S rDNA gene sequence showed that it was most closely related to Penicillium sp. (HQ608083.1). Strain K35 was used to ferment the adventitious root extract, and the fermentation products were analyzed by high-performance liquid chromatography. The results showed that the content of the rare ginsenoside CK was 0.253 mg mL-1 under the optimal converting conditions of 9 d of fermentation at pH 7.0 in LL medium, which was significantly higher than that in the adventitious roots of ginseng. Conclusion: These findings may not only solve the problem of low productivity of metabolite in ginseng root culture but may also result in the development of a new valuable method of manufacturing ginsenoside CK.

AtTCTP2 mRNA and protein movement correlates with formation of adventitious roots in tobacco.

The Translationally Controlled Tumor Proteins, or TCTP, is a superfamily of exclusively eukaryotic proteins essential in the regulation of proliferation and general growth. However, it is clear that these are multifunctional proteins given (1) the pleiotropic effects of its mutations, and (2), the multiple processes in which this protein is involved. TCTP function in general is conserved, since Arabidopsis AtTCTP1 can rescue a Drosophila mutant, and vice versa. It has become clear, however, that these proteins may have "taxon-specific" functions. In the case of plants, mRNA and/or proteins have been found in the phloem translocation stream of different species, suggesting a role in long-distance signaling. We have found that a second Arabidopsis TCTP gene, AtTCTP2, codes for a protein that moves long-distance through a graft union in tobacco. Interestingly, the mRNA is also transported long-distance. Both mRNA and protein move long-distance; interestingly, the movement, while more efficient from source to sink tissues, also occurs in the opposite direction. The protein reaches the nuclei of parenchyma cells and adventitious roots. Furthermore, it is clear that the long-distance delivery of AtTCTP2 protein and mRNA is required for the induction of adventitious roots. A model is presented that accounts for these observations.

Long distance movement of an Arabidopsis Translationally Controlled Tumor Protein (AtTCTP2) mRNA and protein in tobacco.

Translationally Controlled Tumor Protein (TCTP) is an almost ubiquitous protein found in eukaryotes, fundamental for the regulation of development and general growth. The multiple functions of TCTP have been inferred from its involvement in several cell pathways, but the specific function of TCTP is still not known in detail. On the other hand, TCTP seems to respond to a plethora of external signals, and appears to be regulated at the transcriptional and/or translational levels by mechanisms yet to be determined. In the present work, we analyzed the capacity of AtTCTP2 gene products (mRNA and protein) to translocate long distance through tobacco heterografts (transgenic/WT and WT/transgenic). The results indicate that both AtTCTP2 mRNA and protein are capable of moving long distance in both directions (stock-scion and scion-stock) with a tendency for movement from source to sink tissue (stock to scion). Interestingly, aerial roots emerged only in heterografts where the protein was detected in both stock and scion, suggesting a correlation between the presence of AtTCTP2 and aerial root appearance. More detailed analysis showed that these aerial roots harbored the transgene and expressed both transcript and protein. In addition, the protein localization pattern in transgenic aerial and primary roots was basically the same, indicating specific nuclear destination in roots, but also in leaves. These findings provide an approach to understand the role of long-distance movement in the function of plant TCTPs, supporting the notion that some of these act in a non-cell autonomous manner, as the human counterpart, the Histamine Releasing Factor (HRF).

Enraizamento de estacas de Sebastiania schottiana Müll. Arg. / Rooting of Sebastiania schottiana Müll. Arg. cuttings

O pouco domínio dos processos envolvidos no enraizamento de estacas de diversas espécies florestais tem sido um fator limitador para a produção de mudas via propagação vegetativa, impedindo possíveis ganhos econômicos e ecológicos nas atividades de reflorestamento e recuperação de áreas degradadas. O objetivo deste estudo foi verificar o potencial de enraizamento de estacas de Sebastiania schottiana, submetidas a diferentes doses e tempos de imersão em produto comercial Orgasol® FTS (composto de aminoácidos e micronutrientes). Estacas basais, medianas e apicais tiveram suas bases imersas em Orgasol® FTS nas doses de 0; 5; 10 e 15mL L-1, durante 1 minuto. O delineamento experimental foi realizado em blocos ao acaso, com três repetições de 20 estacas por parcela. Aos 75 dias, avaliou-se a porcentagem de estacas enraizadas, o comprimento e diâmetro da raiz mais longa. Em um segundo experimento, estacas basais e medianas foram tratadas em 15mL L-1 do produto, durante 0, 15, 30 e 45 minutos. O delineamento experimental foi realizado em blocos ao acaso, com três repetições e 20 estacas por parcela. Aos 150 dias, avaliou-se a porcentagem de estacas enraizadas, massa seca das raízes e o comprimento e diâmetro da raiz mais longa. No primeiro experimento, o aumento da dose do produto promoveu um maior potencial de enraizamento em todos os tipos de estacas, com maior porcentagem de estacas enraizadas no tratamento com 15mL L-1 do produto. No segundo experimento, os maiores potenciais de enraizamento foram observados em estacas basais e medianas tratadas com 15mL L-1 do produto, por 45 minutos. O uso do produto comercial Orgasol® FTS favoreceu a indução de raízes adventícias em estacas de Sebastiania schottiana.

The aim of this study was to verify the rooting potential of Sebastiania schottiana cuttings treated with different doses and immersion times in Orgasol® FTS (composed with amino acids and micronutrients). In a first trial, basal, median and apical cuttings had their bases immersed in Orgasol® FTS at levels of 0, 5, 10 and 15mL L-1, for 1 minute. The experimental design was in random blocks, with three replicates and 20 cuttings per plot. At 75 days, the rooted cuttings percentage, the length and diameter of the longest root were evaluated. In a second trial, basal and median cuttings were treated for 0, 15, 30 and 45 minutes in 15mL L-1 of Orgasol® FTS. The experimental design was in random blocks, with three replicates of 20 cuttings per plot. At 150 day, the rooted cuttings percentage, dry roots mass and the length and diameter of the longest root were evaluated. In the first trial, higher levels of product was beneficial to rooting, it was observed the largets rooted cuttings percentage in the treatment with 15mL L-1 of product. In second trial, the higher rooting potential was observed in the basal and median cuttings treated by 45 minutes in 15mL L-1 of product. The use of orgasol® FTS promotes adventitious roots in Sebastiania schottiana cuttings.

Enraizamento de estacas de Sebastiania schottiana Müll. Arg

The aim of this study was to verify the rooting potential of Sebastiania schottiana cuttings treated with different doses and immersion times in Orgasol® FTS (composed with amino acids and micronutrients). In a first trial, basal, median and apical cuttings had their bases immersed in Orgasol® FTS at levels of 0, 5, 10 and 15mL L-1, for 1 minute. The experimental design was in random blocks, with three replicates and 20 cuttings per plot. At 75 days, the rooted cuttings percentage, the length and diameter of the longest root were evaluated. In a second trial, basal and median cuttings were treated for 0, 15, 30 and 45 minutes in 15mL L-1 of Orgasol® FTS. The experimental design was in random blocks, with three replicates of 20 cuttings per plot. At 150 day, the rooted cuttings percentage, dry roots mass and the length and diameter of the longest root were evaluated. In the first trial, higher levels of product was beneficial to rooting, it was observed the largets rooted cuttings percentage in the treatment with 15mL L-1 of product. In second trial, the higher rooting potential was observed in the basal and median cuttings treated by 45 minutes in 15mL L-1 of product. The use of orgasol® FTS promotes adventitious roots in Sebastiania schottiana cuttings.

O pouco domínio dos processos envolvidos no enraizamento de estacas de diversas espécies florestais tem sido um fator limitador para a produção de mudas via propagação vegetativa, impedindo possíveis ganhos econômicos e ecológicos nas atividades de reflorestamento e recuperação de áreas degradadas. O objetivo deste estudo foi verificar o potencial de enraizamento de estacas de Sebastiania schottiana, submetidas a diferentes doses e tempos de imersão em produto comercial Orgasol® FTS (composto de aminoácidos e micronutrientes). Estacas basais, medianas e apicais tiveram suas bases imersas em Orgasol® FTS nas doses de 0; 5; 10 e 15mL L-1, durante 1 minuto. O delineamento experimental foi realizado em blocos ao acaso, com três repetições de 20 estacas por parcela. Aos 75 dias, avaliou-se a porcentagem de estacas enraizadas, o comprimento e diâmetro da raiz mais longa. Em um segundo experimento, estacas basais e medianas foram tratadas em 15mL L-1 do produto, durante 0, 15, 30 e 45 minutos. O delineamento experimental foi realizado em blocos ao acaso, com três repetições e 20 estacas por parcela. Aos 150 dias, avaliou-se a porcentagem de estacas enraizadas, massa seca das raízes e o comprimento e diâmetro da raiz mais longa. No primeiro experimento, o aumento da dose do produto promoveu um maior potencial de enraizamento em todos os tipos de estacas, com maior porcentagem de estacas enraizadas no tratamento com 15mL L-1 do produto. No segundo experimento, os maiores potenciais de enraizamento foram observados em estacas basais e medianas tratadas com 15mL L-1 do produto, por 45 minutos. O uso do produto comercial Orgasol® FTS favoreceu a indução de raízes adventícias em estacas de Sebastiania schottiana.

Enraizamento de estacas de Sebastiania schottiana Müll. Arg.

The aim of this study was to verify the rooting potential of Sebastiania schottiana cuttings treated with different doses and immersion times in Orgasol® FTS (composed with amino acids and micronutrients). In a first trial, basal, median and apical cuttings had their bases immersed in Orgasol® FTS at levels of 0, 5, 10 and 15mL L-1, for 1 minute. The experimental design was in random blocks, with three replicates and 20 cuttings per plot. At 75 days, the rooted cuttings percentage, the length and diameter of the longest root were evaluated. In a second trial, basal and median cuttings were treated for 0, 15, 30 and 45 minutes in 15mL L-1 of Orgasol® FTS. The experimental design was in random blocks, with three replicates of 20 cuttings per plot. At 150 day, the rooted cuttings percentage, dry roots mass and the length and diameter of the longest root were evaluated. In the first trial, higher levels of product was beneficial to rooting, it was observed the largets rooted cuttings percentage in the treatment with 15mL L-1 of product. In second trial, the higher rooting potential was observed in the basal and median cuttings treated by 45 minutes in 15mL L-1 of product. The use of orgasol® FTS promotes adventitious roots in Sebastiania schottiana cuttings.

O pouco domínio dos processos envolvidos no enraizamento de estacas de diversas espécies florestais tem sido um fator limitador para a produção de mudas via propagação vegetativa, impedindo possíveis ganhos econômicos e ecológicos nas atividades de reflorestamento e recuperação de áreas degradadas. O objetivo deste estudo foi verificar o potencial de enraizamento de estacas de Sebastiania schottiana, submetidas a diferentes doses e tempos de imersão em produto comercial Orgasol® FTS (composto de aminoácidos e micronutrientes). Estacas basais, medianas e apicais tiveram suas bases imersas em Orgasol® FTS nas doses de 0; 5; 10 e 15mL L-1, durante 1 minuto. O delineamento experimental foi realizado em blocos ao acaso, com três repetições de 20 estacas por parcela. Aos 75 dias, avaliou-se a porcentagem de estacas enraizadas, o comprimento e diâmetro da raiz mais longa. Em um segundo experimento, estacas basais e medianas foram tratadas em 15mL L-1 do produto, durante 0, 15, 30 e 45 minutos. O delineamento experimental foi realizado em blocos ao acaso, com três repetições e 20 estacas por parcela. Aos 150 dias, avaliou-se a porcentagem de estacas enraizadas, massa seca das raízes e o comprimento e diâmetro da raiz mais longa. No primeiro experimento, o aumento da dose do produto promoveu um maior potencial de enraizamento em todos os tipos de estacas, com maior porcentagem de estacas enraizadas no tratamento com 15mL L-1 do produto. No segundo experimento, os maiores potenciais de enraizamento foram observados em estacas basais e medianas tratadas com 15mL L-1 do produto, por 45 minutos. O uso do produto comercial Orgasol® FTS favoreceu a indução de raízes adventícias em estacas de Sebastiania schottiana.

Enraizamento de estacas de Sebastiania schottiana Müll. Arg.

The aim of this study was to verify the rooting potential of Sebastiania schottiana cuttings treated with different doses and immersion times in Orgasol® FTS (composed with amino acids and micronutrients). In a first trial, basal, median and apical cuttings had their bases immersed in Orgasol® FTS at levels of 0, 5, 10 and 15mL L-1, for 1 minute. The experimental design was in random blocks, with three replicates and 20 cuttings per plot. At 75 days, the rooted cuttings percentage, the length and diameter of the longest root were evaluated. In a second trial, basal and median cuttings were treated for 0, 15, 30 and 45 minutes in 15mL L-1 of Orgasol® FTS. The experimental design was in random blocks, with three replicates of 20 cuttings per plot. At 150 day, the rooted cuttings percentage, dry roots mass and the length and diameter of the longest root were evaluated. In the first trial, higher levels of product was beneficial to rooting, it was observed the largets rooted cuttings percentage in the treatment with 15mL L-1 of product. In second trial, the higher rooting potential was observed in the basal and median cuttings treated by 45 minutes in 15mL L-1 of product. The use of orgasol® FTS promotes adventitious roots in Sebastiania schottiana cuttings.

O pouco domínio dos processos envolvidos no enraizamento de estacas de diversas espécies florestais tem sido um fator limitador para a produção de mudas via propagação vegetativa, impedindo possíveis ganhos econômicos e ecológicos nas atividades de reflorestamento e recuperação de áreas degradadas. O objetivo deste estudo foi verificar o potencial de enraizamento de estacas de Sebastiania schottiana, submetidas a diferentes doses e tempos de imersão em produto comercial Orgasol® FTS (composto de aminoácidos e micronutrientes). Estacas basais, medianas e apicais tiveram suas bases imersas em Orgasol® FTS nas doses de 0; 5; 10 e 15mL L-1, durante 1 minuto. O delineamento experimental foi realizado em blocos ao acaso, com três repetições de 20 estacas por parcela. Aos 75 dias, avaliou-se a porcentagem de estacas enraizadas, o comprimento e diâmetro da raiz mais longa. Em um segundo experimento, estacas basais e medianas foram tratadas em 15mL L-1 do produto, durante 0, 15, 30 e 45 minutos. O delineamento experimental foi realizado em blocos ao acaso, com três repetições e 20 estacas por parcela. Aos 150 dias, avaliou-se a porcentagem de estacas enraizadas, massa seca das raízes e o comprimento e diâmetro da raiz mais longa. No primeiro experimento, o aumento da dose do produto promoveu um maior potencial de enraizamento em todos os tipos de estacas, com maior porcentagem de estacas enraizadas no tratamento com 15mL L-1 do produto. No segundo experimento, os maiores potenciais de enraizamento foram observados em estacas basais e medianas tratadas com 15mL L-1 do produto, por 45 minutos. O uso do produto comercial Orgasol® FTS favoreceu a indução de raízes adventícias em estacas de Sebastiania schottiana.

ASPECTOS ANATÔMICOS DO ENRAIZAMENTO DA VIDEIRA MUSCADÍNIA (Vitis rotundifolia Michx.) ATRAVÉS DE ALPORQUIA

The propagation of grapes is ordinarily carried out by vegetative methods like cuttings and graftings, which not always present satisfactory results, especially for those species with low rooting ability, endangering the commercial production. The muscadine grape (Vitis rotundifolia Michx.) is considered recalcitrant for rooting. Its propagation by cuttings shows that growth regulators have few or no benefits on rooting. Nowadays, air-layering is reported as a propagation method that promotes good rooting when combined with the application of growth regulators. This work aimed to evaluate the efficiency of air-layering process in relation to muscadine grape rooting, as well as to study the callus and the adventitious root anatomy. The results showed that the practice of ringing is more successfull than the bark retreating for rooting. The addition of naphtalene acetic acid did not affect significantly the rooting. The adventitious roots appeard close to the cambial area at the node and internode branch regions. There was no root formation from callus tissue. Its tissue was characterized by meristematic activity and absence of starch.

A multiplicação das videiras é comumente realizada através de processos vegetativos como a estaquia e a enxertia, os quais nem sempre apresentam resultados satisfatórios, especialmente para as espécies de difícil enraizamento, comprometendo a produção comercial. A uva muscadínia (Vitis rotundifolia Michx.) é considerada uma planta difícil de enraizar. Sua propagação através da estaquia mostra que o emprego de reguladores vegetais proporciona pouco ou nenhum benefício ao enraizamento das estacas. Atualmente, a alporquia em frutíferas vem se apresentando como um método de propagação que proporciona um bom enraizamento, aliado à aplicação de reguladores vegetais. Este trabalho procurou avaliar a eficiência do processo de alporquia com relação ao enraizamento da uva muscadínia bem como estudar a anatomia dos calos e das raízes adventícias. Pode-se concluir que a prática do anelamento mostra-se mais efetiva em proporcionar o enraizamento do que a retirada de lascas. A adição de ácido naftalenacético não afetou significativamente o enraizamento. As raízes adventícias apareceram nas proximidades da região cambial, nas regiões nodais e internodais dos ramos. Não ocorreu a formação de raízes diretamente do calo. O tecido do calo caracterizou-se por ser meristematicamente ativo e não apresentar amido.

ASPECTOS ANATÔMICOS DO ENRAIZAMENTO DA VIDEIRA MUSCADÍNIA (Vitis rotundifolia Michx.) ATRAVÉS DE ALPORQUIA

The propagation of grapes is ordinarily carried out by vegetative methods like cuttings and graftings, which not always present satisfactory results, especially for those species with low rooting ability, endangering the commercial production. The muscadine grape (Vitis rotundifolia Michx.) is considered recalcitrant for rooting. Its propagation by cuttings shows that growth regulators have few or no benefits on rooting. Nowadays, air-layering is reported as a propagation method that promotes good rooting when combined with the application of growth regulators. This work aimed to evaluate the efficiency of air-layering process in relation to muscadine grape rooting, as well as to study the callus and the adventitious root anatomy. The results showed that the practice of ringing is more successfull than the bark retreating for rooting. The addition of naphtalene acetic acid did not affect significantly the rooting. The adventitious roots appeard close to the cambial area at the node and internode branch regions. There was no root formation from callus tissue. Its tissue was characterized by meristematic activity and absence of starch.

A multiplicação das videiras é comumente realizada através de processos vegetativos como a estaquia e a enxertia, os quais nem sempre apresentam resultados satisfatórios, especialmente para as espécies de difícil enraizamento, comprometendo a produção comercial. A uva muscadínia (Vitis rotundifolia Michx.) é considerada uma planta difícil de enraizar. Sua propagação através da estaquia mostra que o emprego de reguladores vegetais proporciona pouco ou nenhum benefício ao enraizamento das estacas. Atualmente, a alporquia em frutíferas vem se apresentando como um método de propagação que proporciona um bom enraizamento, aliado à aplicação de reguladores vegetais. Este trabalho procurou avaliar a eficiência do processo de alporquia com relação ao enraizamento da uva muscadínia bem como estudar a anatomia dos calos e das raízes adventícias. Pode-se concluir que a prática do anelamento mostra-se mais efetiva em proporcionar o enraizamento do que a retirada de lascas. A adição de ácido naftalenacético não afetou significativamente o enraizamento. As raízes adventícias apareceram nas proximidades da região cambial, nas regiões nodais e internodais dos ramos. Não ocorreu a formação de raízes diretamente do calo. O tecido do calo caracterizou-se por ser meristematicamente ativo e não apresentar amido.