Baru (Dipteryx alata Vogel), a woody species characteristic of Cerrado and its phytoremediation potential.

Baru (Dipteryx alata Vogel) is a native tree plant, widely distributed in Brazil, and has a growth and development in acidic soils like Cerrado, indicating a probable tolerance to adverse soil conditions, such as the high concentration of metals and the acidic pH. Due to the lack of information about the tolerance of this species to metals and the possibility of being used in the recovery of degraded areas and/or in phytoremediation, this work was developed with the objective of evaluating the in vitro germination and growth capacity of baru in medium supplemented with different concentrations of aluminum, iron, and manganese, as well as through chemical analysis, to determine the concentration of metals accumulated in cultivated plants in these conditions. The treatments consisted in different concentrations of metals: aluminum, Al3+ (0, 3.5, 7.0, 10.5, 21.0, or 42.0 mg L-1); iron, Fe3+ (0, 2.5, 4.9, 7.4, 14.7, or 29.4 mg L-1); and manganese, Mn2+ (0, 0.4, 0.8, 1.2, 2.4, or 4.8 mg L-1) added to the medium WPM. The tested values were based on using the lower concentration as the limit value, calculated based on risk to human health in accordance with CONAMA resolution 420/2009 for groundwater. At 60 days of cultivation, the percentage of germination, the average number of leaves, the length of the main root and the aerial part, the fresh and dry mass of the aerial part and the root system and the cations concentration Al3+, Fe3+ and Mn2+ in the plant biomass, were evaluated. The results showed that under the conditions in which the experiment was conducted, germination and in vitro growth of baru were not affected by the presence in high concentrations of any of the evaluated metals, with no differences in the percentage of germination and plant growth, as well as typical toxicity characteristics were not observed, such as changes in root morphology, chlorosis, or tissue oxidation. The absence of toxicity symptoms in baru plants, in the presence of Al3+, Fe3+, and Mn2+, indicate that the species is tolerant to these metals. The accumulation of Al3+ and Fe3+ in the plant biomass at the beginning of growth, simultaneously with the increase in the concentrations of these elements in the culture medium, indicates that this species can be used for phytoremediation, because it is a probable accumulator of these elements throughout its development, given the presence in significant concentrations of these elements also in the seeds.

Seedling Establishment of Tall Fescue Exposed to Long-Term Starvation Stress.

In germinating seeds under unfavorable environmental conditions, the mobilization of stores in the cotyledons is delayed, which may result in a different modulation of carbohydrates balance and a decrease in seedling vigor. Tall fescue (Festuca arundinacea Schreb.) caryopses grown at 4°C in the dark for an extended period in complete absence of nutrients, showed an unexpected ability to survive. Seedlings grown at 4°C for 210 days were morphologically identical to seedlings grown at 23°C for 21 days. After 400 days, seedlings grown at 4°C were able to differentiate plastids to chloroplast in just few days once transferred to the light and 23°C. Tall fescue exposed to prolonged period at 4°C showed marked anatomical changes: cell wall thickening, undifferentiated plastids, more root hairs and less xylem lignification. Physiological modifications were also observed, in particular related to sugar content, GA and ABA levels and amylolytic enzymes pattern. The phytohormones profiles exhibited at 4 and 23°C were comparable when normalized to the respective physiological states. Both the onset and the completion of germination were linked to GA and ABA levels, as well as to the ratio between these two hormones. All plants showed a sharp decline in carbohydrate content, with a consequent onset of gradual sugar starvation. This explained the slowed then full arrest in growth under both treatment regimes. The analysis of amylolytic activity showed that Ca2+ played a central role in the stabilization of several isoforms. Overall, convergence of starvation and hormone signals meet in crosstalk to regulate germination, growth and development in tall fescue.

Influência do meio de cultura, tipo e concentração de citocininas na multiplicação in vitro de amoreira-preta e framboeseira / The influence of culture medium, cytokinin type and concentrations on in vitro multiplication of blackberry and raspberry

A amoreira-preta e a framboeseira são espécies pouco cultivadas no Brasil, porém representam uma ótima opção de diversificação para pequenas propriedades, por serem rústicas e com elevada produtividade. A propagação dessas espécies dá-se, principalmente, por meio de estacas de raiz e mesmo de hastes novas, porém, já é crescente o interesse pelo uso da micropropagação como um método alternativo de propagação vegetativa de plantas frutíferas. No entanto, existe a necessidade de se ajustar, para cada espécie, e/ou cultivar, as melhores condições de cultivo, para que se obtenha sucesso no processo. Assim, neste trabalho objetivou-se determinar o melhor meio de cultura (MS e WPM), o efeito das citocininas (BAP, 2iP, Zeatina) e suas concentrações (0; 7,5 ;15 e 22,5 μM) na multiplicação in vitro de amoreira-preta 'Xavante' e de framboeseira 'Batum' e 'Heritage'. De acordo com os resultados obtidos, conclui-se que, o meio MS e a citocinina BAP na concentração de 15 μM foi mais eficiente para ambas as espécies e cultivares, induzindo maior número médio de folhas, brotações e gemas. Quanto ao comprimento das brotações, observou-se um comportamento diferenciado entre espécie, cultivar e regulador. Para amoreira-preta, o cultivo em meio MS na ausência de regulador promoveu o aumento do comprimento das brotações, enquanto que para framboeseira 'Batum' e 'Heritage', melhores resultados foram obtidos na presença de citocininas, respectivamente, Zeatina e 2iP, independentemente das concentrações utilizadas.

The blackberry and raspberry are species little cultivated in Brazil. However, they represent a valuable diversification option for small farms, once they are rustic and very productive. Root cuttings and softwood stem are the most widely practiced type of propagation. Recently, there has been an increased interest in the use of micropropagation as an alternative technique for fruit plant propagation. Nevertheless, there is a need to adjust the appropriate cultivation condition for each species and/or cultivar for the process to succeed. Therefore, this research aimed at determining the most suitable culture medium (MS and WPM), the effect of cytokinines (BAP, 2iP, Zea) and their concentrations (0; 7,5; 15 e 22,5μM) on in vitro multiplication of blackberry cultivar Xavante and raspberry cultivar Batum and Heritage. The results have shown that the medium MS and the cytokinin BAP at 13 μM for the blackberry 'Xavante' and 12 μM for raspberry 'Batum' and 'Heritage' were more efficient, increasing average leaf number, shoots and buds. For the blackberry, cultivation in MS medium in the absence of regulator promoted an increase in shoot length, whereas for 'Batum' and 'Heritage' raspberries, better results were obtained in the presence of citocinines - zeatin for Batum and 2iP for Heritage, independently of the concentrations.

Enraizamento in vitro de mirtilo em condições fotoautotróficas / In vitro rooting of blueberry under photoautotrophic conditions

O objetivo deste trabalho foi avaliar a eficiência do enraizamento fotoautotrófico de mirtilo (Vaccinium ashei Reade), cultivar 'Delite', comparando o efeito da luz natural (casa de vegetação) e da luz artificial (sala de crescimento) durante duas épocas do ano (verão e inverno), bem como o efeito de três concentrações de sacarose (0; 15 e 30g L-1) adicionadas ao meio de cultura e de diferentes tipos de vedação dos frascos de cultivo (alumínio, algodão e filme plástico). Após 60 dias de enraizamento in vitro em meio de cultura WPM, contendo 9µM L-1 de AIB, observou-se que o enraizamento em meio de cultura livre de sacarose promoveu o aumento do número de raízes e da porcentagem de enraizamento e, quando associado ao fechamento dos frascos com algodão, favoreceu, também, o incremento do comprimento das raízes e da massa fresca total. Quanto ao ambiente de cultivo e às épocas do ano, concluiu-se que o enraizamento pode ser realizado com sucesso de forma fotoautotrófica e, durante o verão, independentemente do ambiente de cultivo, verifica-se um aumento do comprimento de raízes, da porcentagem de enraizamento e da massa fresca total.

The aim of this research was to assess the photoautotrofic rooting efficiency of blueberry (Vaccinium ashei Reade), cultivar 'Delite' by comparing the effect between natural light (greenhouse) and artificial light (growth room) in two seasons (summer and winter), as well as the effect of different three sucrose concentrations (0; 15 or 30g L-1) added to the culture medium and different types of flasks closure (aluminum, cotton and plastic film). After 60 days of in vitro rooting on WPM medium culture containing 9µM L-1 AIB, rooting in free-sucrose culture medium promoted an increased in the number of roots and rooting percentage; and, whether associated to cotton closed, there was an increase in length of roots and in the total fresh weight. Regarding environment growth and season, rooting could be successfully realized under photoautotrophic conditions. At summer, it was verified an increase in roots length, rooting percentage and total fresh weight independently of environment growth.

Diferentes substratos e ambientes no enraizamento in vitro de mirtilo / Different substrates and environment conditions on in vitro rooting of blueberry

O objetivo neste trabalho foi comparar a capacidade de enraizamento in vitro de mirtilo (Vaccinium ashei Reade cv. 'Delite' e V. corymbosum L. cv. 'Georgiagem') e estudar o efeito de substratos alternativos ao ágar (perlita, vermiculita e ágar + carvão ativado) adicionados ao meio de cultura 'WPM' contendo 7µM L-1 de AIB e o efeito da luminosidade por meio do cultivo em diferentes ambientes: sala de crescimento convencional e casa de vegetação. Concluiu-se que o uso de perlita, seguido da vermiculita, promovem o aumento do número e comprimento de raízes, matéria fresca total e radicular e maiores porcentagens de enraizamento. A adição de carvão ativado inibe o enraizamento. O ambiente de cultivo não alterou o número de raízes formadas. A cultivar 'Georgiagem' apresentou maiores porcentagens de enraizamento quando comparada a cv. 'Delite', independentemente do local de cultivo e substrato.

The aim of this research was to compare the in vitro rooting ability of blueberry (Vaccinium ashei Reade cv. 'Delite' and V. corymbosum L. cv. 'Georgiagem'), to study the effect of alternative substrate instead of agar (perlite, vermiculite and agar + activated charcoal) added to the WPM culture medium containing 7µM L-1 of AIB, and the light effect by raising the explants in different growth environment: conventional growth room and greenhouse. The use of perlite followed by vermiculite increased roots number and length, total fresh weight and root weight and rooting percentage. The addition of activated charcoal inhibited rooting. The environment condition did not alter the number of formed roots. The cv. 'Georgiagem' showed the highest percentages of rooting whether compared cv. 'Delite', independently of growth environment and substrate.

Multiplicação e enraizamento in vitro de amoreira-preta 'Xavante': efeito da concentração de sais, do tipo de explante e de carvão ativado no meio de cultura / Blackberry 'Xavante' in vitro multiplication and rooting: salt concentrations effect, explant type, and activated coal on culture medium

Atualmente, além da propagação tradicional, a micropropagação da amoreira-preta é considerada uma alternativa viável, com o intuito de obter-se plantas livres de vírus, geneticamente uniformes e em curto espaço de tempo. Objetivou-se, com este experimento, determinar o melhor tipo de explante e concentração de sais para a multiplicação in vitro e a melhor concentração de carvão ativado e de sais no meio de cultura, para o enraizamento in vitro de amoreira-preta 'Xavante'. O primeiro experimento constituiu-se de segmentos nodais caulinares com cerca de 1 cm, oriundas do cultivo in vitro, inoculadas em quatro diferentes concentrações de meio MS, suplementada com 7,5 µM de BAP, 30 g L-1 de sacarose, 100 mg L-1 de mio-inositol e 6 g L-1 de ágar, e dois tipos de explante, totalizando 8 tratamentos. O segundo experimento constituiu-se de microestacas apicais, com cerca de 1 a 1,5 cm de comprimento, e duas folhas, inoculadas em três diferentes concentrações de meio MS, acrescido de 30 g L-1 de sacarose, 100 mg L-1 de mio-inositol e 6 g L-1 de ágar e suplementado com três concentrações de carvão ativado, totalizando nove tratamentos, com delineamento inteiramente casualizado. Pode-se concluir que o T1, ou seja, explante com folhas, na concentração de 125 por cento de sais do meio MS foi mais eficiente, induzindo maior número de folhas, gemas, brotações e comprimento das brotações e que o uso de 75 por cento de sais sem a suplementação de carvão ativado é o mais indicado para o enraizamento in vitro de amoreira-preta 'Xavante'.

Besides the traditional propagation, blackberry micropropagation has currently been considered a feasible alternative, with the purpose of obtaining plants free from virus, genetically uniform and in the short run. The objective of this experiment was to determine the best explant type and the optimum in vitro multiplication salts concentration as well as to determine the activated coal and salts optimum concentrations in culture medium for. The first experiment constituted of nodal segments with 1 cm, originated from of the in vitro cultivation, inoculated at four different MS medium concentrations, supplemented with 7.5 µM BAP, 30 g L-1 sucrose, 100 mg L-1 myo-inositol and 6 g L-1 agar, and with two types of explants, which totaled 8 treatments. The second experiment constituted of apex microcutting, having about 1 to 1.5 cm length, and two leaves were inoculated at three different concentrations of MS medium, added of 30 g L-1 sucrose, 100 mg L-1 myo-inositol and 6 g L-1 agar and supplemented with three different activated coal concentrations, totaling nine treatments. It can be inferred that T1, in other words, explants with leaves, were more efficient at 125 percent MS salt concentration on culture medium, thereby inducing larger number of leaves, buds, shoots and shoot length, and that the use of 75 percent salt concentration without activated coal is the most suitable one for the blackberry 'Xavante' in vitro rooting.

Micropropagação como técnica de rejuvenescimento em mirtilo (Vaccinium ashei Reade) cultivar climax / Micropropagation as a rejuvenation technique in rabbiteye blueberry (Vaccinium ashei Reade) cultivar climax

Objetivou-se com este experimento avaliar o rejuvenescimento do material vegetal através da técnica de micropropagação na produção de mudas de mirtilo, cv. Climax. Os tratamentos aplicados constituíram-se de dois tipos de citocininas (zeatina e 2iP), em quatro concentrações (0; 2,5; 5,0 e 7,5 mg.L-1) e duas fontes de explantes (plantas micropropagadas e plantas obtidas através da germinação de sementes in vitro). O delineamento experimental utilizado foi inteiramente casualizado, em esquema fatorial 2x4x2. Aos 60 dias após a instalação do experimento avaliou-se o número médio de brotos e de gemas por explante, o comprimento médio dos brotos e a taxa de multiplicação. Concluiu-se que plantas de mirtilo, micropropagadas na presença de citocinina e submetidas a sucessivas repicagens, demonstram elevada habilidade de rejuvenescimento in vitro do material adulto, podendo ser comparadas às plantas obtidas de semente, tanto na capacidade de emitir novas brotações, quanto no número de gemas e taxa de multiplicação.

This experiment was installed aiming to evaluate the plant rejuvenation capacity of rabbiteye blueberry seedlings cultivar Climax by using micropropagation technique. The treatments consisted of two cytokinin types (zeatin and 2iP), in four concentrations (0; 2.5; 5.0 and 7.5 mg.L-1) and two sources of explants (micropropagated plants and plants from in vitro seeds germination). The experiment was carried out in a 2x4x2 factorial arranged in a randomized complete design. After 60 days from experiment installation it was assessed the shoots average number and shoots average length, buds average number and the multiplication rate. In conclusion, the present results suggest that the micropropagated rabbiteye blueberry plants in the presence of cytokinin and submitted at successive cuttings showed a high in vitro rejuvenation ability of the adult material, which might be compared to the plants germinated in vitro, in the capacity of emitting new shoots as well as in the buds number and multiplication rate.

Aib e substrato na produção de mudas de mirtilo cv. "Climax" através de microestaquia / Iba and substrate in the plantlets production of blueberry cv. 'Climax' through microcuttings

Embora no Sul do Brasil o mirtilo esteja sendo pesquisado e produzido como uma nova alternativa na fruticultura, a maioria das mudas produzidas são obtidas pela propagação vegetativa, através do uso de estacas, e os resultados obtidos são insatisfatórios. Dessa forma, o objetivo deste trabalho foi testar a capacidade de enraizamento de mirtilo "rabbiteye", através da técnica de microestaquia. Microestacas provenientes de plantas aclimatadas de Vaccinium ashey Reade, cv. "Climax", obtidas através de micropropagação, foram testadas. O experimento foi conduzido em casa de vegetação usando dois tipos de microestacas (média e apical), dois substratos (areia e Plantmax®) e três concentrações de AIB (0, 1000 e 2000mg L-1). Aos 60 dias após a instalação do experimento, foi avaliada a percentagem de microestacas enraizadas, a percentagem de microestacas sobreviventes, o número médio de raízes por microestaca, o comprimento médio das raízes e o comprimento da raiz mais desenvolvida. Concluiu-se que a microestaquia pode ser uma técnica eficiente na produção de mudas de mirtilo, através do uso de plantas-matrizes micropropagadas. O emprego de microestacas oriundas da porção mediana proporcionou elevados índices de enraizamento e sobrevivência, independentemente da concentração de AIB utilizada. Por outro lado, para microestacas apicais, a aplicação de AIB foi fundamental para o enraizamento.

Although blueberries in the South of Brazil have been researched and produced as a new alternative in the horticulture, the majority of plants are propagated vegetatively through the use of cuttings and the results obtained are unsatisfactory. In this way, this research was aimed at testing the rooting ability of rabbiteye Blueberry by microcuttings techniques. Microcuttings from acclimated plants of Vaccinium ashey Reade cv. Climax obtained through micropropagation were tested. The experiment was carried out in a greenhouse using two types of microcuttings (middle and apex shoots), two substrate (sand and Plantmax®) and three concentrations of indole-3butyric-acid (0, 1000, and 2000mg L-1). After 60th day, it was evaluated: surviving microcuttings percentage, percentage of rooted microcuttings, roots number, roots length, and length more developed root. We concluded that the microcuttings can be an efficient technique for blueberry plantlets production, by using micropropagated plants as explants donors. The use of microcuttings from middle section provided high percentage of survived and rooted microcuttings, independent of IBA concentration. On the other hand, for cuttings from the apex section, the AIB application was required for rooting improvement.