Micropropagation of Calophyllum brasiliense (Cambess) from nodal segments / Micropropagação de Calophyllum brasiliense (Cambess) a partir de segmentos nodais

Abstract Micropropagation of Calophyllum brasiliense Cambess. (Clusiaceae) is a way to overcome difficulties in achieving large-scale plant production, given the recalcitrant nature of the seeds, irregular fructification and absence of natural vegetative propagation of the species. Cultures were established using nodal segments 2 cm in length, obtained from 1-2 year old seedlings, maintained in a greenhouse. Mercury chloride and Plant Preservative Mixture™ were used in the surface sterilizing stage, better results being achieved with Plant Preservative Mixture™ incorporation in culture medium, at any concentration. Polyvinylpyrrolidone, activated charcoal, cysteine, ascorbic acid or citric acid were added to the culture medium to avoid oxidation. After 30 days of culture, polyvinylpirrolidone and ascorbic acid gave better results, eliminating oxidation in most explants. For shoot multiplication, benzylaminopurine was used in concentrations of 4.4 and 8.8 µM in Woody Plant Medium, resulting in an average of 4.43 and 4.68 shoots per explant, respectively, after 90 days. Indole-3-butyric acid and α-naphthalene acetic acid were used to induce root formation, reaching a maximum rooting rate of 24% with 20µM α-naphthalene acetic acid. For acclimatization. the rooted plants were transferred to Plantmax® substrate and cultured in a greenhouse, reaching 79% of survival after 30 days and 60% after one year.

Resumo A micropropagação de Calophyllum brasiliense Cambess. (Clusiaceae) é uma maneira de superar dificuldades para sua produção em larga escala, devido à natureza recalcitrante das sementes, frutificação irregular e ausência de propagação vegetativa natural da espécie. Culturas foram estabelecidas utilizando segmentos nodais com 2 cm de comprimento, obtidos de plantas com 1 a 2 anos de idade, mantidas em casa de vegetação. Cloreto de mercúrio e Plant Preservative Mixture™ foram utilizados durante a etapa de desinfestação, com melhores resultados alcançados com a incorporação de Plant Preservative Mixture™ ao meio de cultura. Polivinilpirrolidona, carvão ativado, cisteína, ácido ascórbico ou ácido cítrico foram adicionados ao meio de cultura para evitar a oxidação dos explantes. Após 30 dias de cultivo, o uso de polivinilpirrolidona ou ácido ascórbico proporcionou melhores resultados, eliminando a oxidação na maioria dos explantes. Para multiplicação das brotações, benzilaminopurina foi usada em concentrações de 4.4 e 8.8 µM em meio WPM, resultando em uma média de 4.43 e 4.68 brotações por explante, respectivamente, após 90 dias. Ácido indol-3-butírico e ácido α-naftaleno acético foram usados para a indução de raízes, alcançando um enraizamento máximo de 24% com o uso de 20µM de ácido α-naftaleno acético. As plantas enraizadas foram transferidas para substrato Plantmax® e cultivadas em casa de vegetação, alcançando 79% de sobrevivência após 30 dias e 60% após um ano.

Micropropagation of Calophyllum brasiliense (Cambess.) from nodal segments.

Micropropagation of Calophyllum brasiliense Cambess. (Clusiaceae) is a way to overcome difficulties in achieving large-scale plant production, given the recalcitrant nature of the seeds, irregular fructification and absence of natural vegetative propagation of the species. Cultures were established using nodal segments 2 cm in length, obtained from 1-2 year old seedlings, maintained in a greenhouse. Mercury chloride and Plant Preservative Mixture™ were used in the surface sterilizing stage, better results being achieved with Plant Preservative Mixture™ incorporation in culture medium, at any concentration. Polyvinylpyrrolidone, activated charcoal, cysteine, ascorbic acid or citric acid were added to the culture medium to avoid oxidation. After 30 days of culture, polyvinylpirrolidone and ascorbic acid gave better results, eliminating oxidation in most explants. For shoot multiplication, benzylaminopurine was used in concentrations of 4.4 and 8.8 µM in Woody Plant Medium, resulting in an average of 4.43 and 4.68 shoots per explant, respectively, after 90 days. Indole-3-butyric acid and α-naphthalene acetic acid were used to induce root formation, reaching a maximum rooting rate of 24% with 20µM α-naphthalene acetic acid. For acclimatization. the rooted plants were transferred to Plantmax® substrate and cultured in a greenhouse, reaching 79% of survival after 30 days and 60% after one year.

Substratos, concentrações de ácido indolbutírico e tipos de miniestacas no enraizamento de melaleuca (Melaleuca alternifolia Cheel) / Substrates, indolebutyric acid levels and types of minicuttings on the rooting of tea tree (Melaleuca alternifolia Cheel)

Melaleuca alternifolia tem como produto principal o óleo essencial extraído das folhas devido às propriedades antifúngicas e antibacterianas. Pouco se tem relatado sobre a propagação desta espécie, sendo a miniestaquia uma alternativa para a propagação vegetativa de clones superiores visando à implantação de campo de produção. Este trabalho teve como objetivo avaliar o efeito de diferentes substratos, concentrações de AIB, e tipo de miniestaca, no enraizamento de Melaleuca alternifolia. No primeiro experimento foram testados os substratos, areia de granulometria média, Plantmax HT®, Golden-Mix® e vermiculita. No segundo experimento foram avaliadas diferentes concentrações de AIB (0, 500, 1000 e 2000 mg L-1), em dois tipos de miniestacas (apical e mediana). As miniestacas foram confeccionadas com 5 cm de comprimento, mantidas em casa de vegetação com nebulização intermitente, e, após 45 dias do plantio, foram avaliadas as porcentagens de miniestacas enraizadas, com calos e não responsivas, o número de raízes formadas por miniestaca e o comprimento das três maiores raízes (cm). O substrato Golden-Mix® e as miniestacas coletadas da porção apical do ramo submetidas ao tratamento com 500 mg L-1 de AIB apresentaram maior porcentagem de enraizamento e melhor qualidade do sistema radicial.

Melaleuca alternifolia has as major product the essential oil extracted from its leaves due to its antifungal and antibacterial properties. There are scarce reports about the propagation of this species, and minicutting is an alternative for vegetative propagation of superior clones in order to establish a production field. This study aimed to evaluate the effect of different substrates, IBA levels and types of minicuttings on the rooting of Melaleuca alternifolia. In the first experiment, the following substrates were tested: medium sand, Plantmax HT®, Golden-Mix® and vermiculite. In the second experiment, different IBA levels (0, 500, 1000 and 2000 mg L-1) were tested for two minicutting types (apical and medium). Minicuttings were prepared with 5 cm length and were kept in a greenhouse with intermittent mist; then, at 45 days after planting, we evaluated: the percentages of rooted minicuttings, with callus and non-responsive, the number of roots per minicutting and the length of the three longest roots. The substrate Golden-Mix® and the minicuttings collected from the apical part of the branch and treated with 500 mg L-1 IBA presented the largest rooting percentage and the best root system quality.

A xyloglucan from seeds of the native Brazilian species Hymenaea courbaril for micropropagation of Marubakaido and Jonagored apples.

Xyloglucan was extracted from seeds of Hymenaea courbaril and mixed with agar to prepare a solid culture medium used for micropropagation of the Marubakaido apple rootstock (Malus prunifolia Borkh) and cv. Jonagored (Malus domestica). The performance on gels created from a blend of 0.4%agar and 0.2% xyloglucan (w/v) was compared with that on media gelled with a standard concentration 0.6% (w/v) of agar. The growth of shoots and the multiplication rate were higher on the modified culture medium than on the agar-gelled medium. The occurrence of hyperhydric shoots was lower on the modified medium. In the absence of auxin, shoot rooting reached 70% (Marubakaido) and 66% (Jonagored) on the agar-xyloglucan medium and 6.7% and 10.4%, respectively, on the agar medium. When 0.25 microM indole-3-butyric acid (IBA) was added to both media, the modified medium gave better results in terms of rooting percentage and quality of roots than the agar-gelled medium.