Frederico Henrique da Silva Costa

Germinação in vitro de embriões zigóticos de murmuru (Astrocaryum ulei)

Com o presente trabalho objetivou-se avaliar a influencia de concentracoes de sacarose e a idade fisiologica da semente na germinacao in vitro de embrioes zigoticos de murmuru. Frutos em dois estagios de desenvolvimento coletados de plantas do campo tiveram os embrioes excisados, desinfestados e inoculados em meio de cultura de MS com 75% das concentracoes de sais, suplementado com 2,5 g.L-1 de acido giberelico e diferentes concentracoes de sacarose: 15, 30 e 45 g.L-1. Em sala de crescimento, o material foi mantido por 30 dias no escuro, sendo transferido em seguida para condicoes luminosas de 30 me.m-2.s-1, temperatura de 25±2oC e fotoperiodo de 16 horas para completo desenvolvimento. O delineamento estatistico utilizado foi inteiramente casualizado em arranjo fatorial 2 x 3, com seis repeticoes e cinco embrioes por parcela. Apos 30 dias foi avaliada a porcentagem de germinacao e altura das plântulas. Verificou-se que embrioes provenientes de frutos imaturos apresentaram maior porcentagem de germinacao, sendo a concentracao de 30 g.L-1 de sacarosea que proporcionou os melhores resultados dentre as demais testadas. Embrioes provenientes de frutos maduros apresentaram altura de plântulas significativamente maior aos imaturos e tambem para essa variavel, a concentracao de 30 g.L-1 de sacarose foi a que proporcionou os melhores resultados.

Efeito de agentes geleificantes alternativos no meio de cultura no cultivo in vitro de abacaxizeiro e bananeira

Com este trabalho, objetivou-se avaliar a acao do agar e sua substituicao parcial e total pelo amido de mandioca na composicao de meios de cultura de bananeira e abacaxizeiro. Gemas axilares de abacaxizeiro, cvs. Rio Branco e Quinari foram estabelecidas e avaliadas por quatro subcultivos quanto a multiplicacao em meio de MS, suplementado com 2 mg.L-1 de BAP e 0,25 mg.L-1 de ANA, e os seguintes tratamentos: M1: agar (5 g.L-1), M2: agar (2,5 g.L-1) + fecula de mandioca (60 g.L-1), M3: fecula de mandioca (60 g.L-1), e M4: agar (2,5 g.L-1) + fecula de mandioca (30 g.L-1). Num segundo experimento, por tres subcultivos sucessivos brotacoes de bananeira da cv. Grand Naine foram avaliadas quanto a multiplicacao em meio de cultura composto por: MM1: agar (6 g.L-1) ; MM2: agar (3 g.L-1) + fecula de mandioca (30 g.L-1); MM3: fecula de mandioca (60 g.L-1) e; MM4: meio de consistencia liquida estacionario.Estes meios foram suplementados com 0, 2, 4 e 6 mg.L-1 de BAP. Para o abacaxizeiro, verificou-se quea substituicao total do agar pela fecula proporcionou resultados similares aos obtidos com o tratamento com agar. Na combinacao agar + fecula os resultados foram inferiores aos obtidos com os solidificantes usados isoladamente. Para a bananeira, o uso isolado ou combinado da fecula com agar nao proporcionou melhora nas taxas de multiplicacao. Os melhores resultados foram obtidos em meio com agar e 2 mg.L-1 de BAP. O cultivo em meio liquido apresentou o menor indice de multiplicacao.

Efeito da interação entre carvão ativado e N6-benzilaminopurina na propagação in vitro de bananeira, cv. Grand Naine (AAA)

O carvao ativado possui a propriedade de adsorver os compostos fenolicos liberados pela oxidacao dos tecidos lesionados durante o cultivo in vitro. O objetivo deste trabalho foi avaliar os efeitos da interacao entre o carvao ativado e diferentes concentracoes de N6-benzilaminopurina (BAP) na multiplicacao in vitro da bananeira, cv. Grande Naine (AAA). O meio de cultura utilizado foi o MS, solidificado com 5 g.L-1 de agar. O cultivo foi mantido em sala de crescimento a 25±2oC, fotoperiodo de 16 horas e intensidade luminosa de 30 mmol.m-2s-1. Foram avaliadas a presenca e a ausencia de carvao ativado (0 e 3 g.L-1) e quatro concentracoes de BAP (0; 2; 4 e 6 mg.L-1) no meio de cultura. O delineamento foi inteiramente casualizado, com cinco repeticoes, em um sistema fatorial 2x4. Os explantes foram avaliados a cada 30 dias, por um periodo de quatro subcultivos. Apos cada subcultivo, o comprimento de brotacoes, a taxa de multiplicacao, o vigor, o nivel de oxidacao das brotacoes emitidas e o numero de raizes formadas foram avaliados. Independentemente das concentracoes de BAP, o carvao ativado influenciou significativamente em todas as variaveis analisadas. De maneira geral, a adicao de carvao ativado afetou negativamente a taxa de multiplicacao, embora tenha melhorado o vigor e o numero de raizes e diminuido a oxidacao dos explantes. Na ausencia de carvao ativado, o BAP proporcionou as maiores taxas de multiplicacao das brotacoes.

Crescimento de mudas micropropagadas de bananeira aclimatizadas nas condições da Amazônia Sul Ocidental sob a influência de diferentes substratos e recipientes

For laboratories that produce thousands of micropropagated plants regularly, the optimization of the acclimatization phase is of fundamental importance to avoid excessive losses and to promote the development of the plants. The aim of this work was to evaluate the growth of micropropagated banana plantlets during the acclimatization under the influence of different substrates and recipients on conditions of South West Amazon. Shoots of banana, cv. Grand Naine, were rooted in MS medium, being the rooting plants transferred to a nursery, in two types of plastic dibble tubes (115 cm3 and 180 cm3) and six different substrates formulated from different portions of soil, carbonized rice hulls and bovine manure. Evaluations of plant survival, height of the aerial part and pseudostem diameter were carried out each fifteen days, and at the end of 75 days, fresh and dry mass for the roots and aerial parts of the plants were also determined. It was verified that the plant survival was not influenced by the use of the 115 cm3 or 180 cm3 plastic dibble tubes. However, acclimatization accomplished in the 180 cm3 plastic dibble tubes provided larger growth in height and pseudostem diameter of the plants and, consequently, larger accumulation of fresh and dry mass of roots and aerial parts, when compared to the 115 cm3 plastic dibble tubes. Among the substrates, it was observed that bovine manure was fundamental as substrate component to obtain the best results.

Relação entre o tempo de enraizamento in vitro e o crescimento de plantas de bananeira na aclimatização

The objective of the present study was to assess the influence of the exposition time to rooting medium on the in vitro and ex vitro growth of banana plants. As explants, new axillaries buds obtained from the in vitro establishment and multiplication of stem apices of Caipira (AAA), Preciosa (AAAB) and Japira (AAAB) cultivars were used. The MS medium with reduction to 50% of the salt concentration adding 30 g.L-1 of sucrose, 1 mg.L-1 of IBA, and 6 g.L-1 of agar was used to induce rooting. The treatments were analyzed in a 3x4 factorial design, with three cultivars (Caipira, Preciosa and Japira) and four in vitro rooting periods (7, 14, 21 and 28 days), given a total of 12 treatments. At the end of each period, the height of the aerial portion, and number and length of roots were assessed, and the plants were submitted to 90 days of acclimatization. After that, the survival, number and length of roots, pseudostem diameter, and dry weight of the roots, aerial and total portions of the plants were assessed. Generally, the root induction step in the in vitro banana budding occurred up to 14 days of cultivation in rooting medium, and after that, the roots grew only in length. Among the cultivars, it was verified that, with the exception of the pseudostem diameter, the Caipira cultivar showed superior in vitro vegetative growth, and during the acclimatization, the height of the plant, number and length of the roots, and dry mass of the aerial, roots, and total parts, were also superior to the observed in Preciosa and Japira cultivars. After 21 days on rooting medium, the survival rate of the plants in greenhouse reach 100%, in despite of the tested cultivar.

Perda de água e modificações anatômicas em folhas de plantas de bananeiras micropropagadas durante a aclimatização

Studies concerning factors involved in the adaptation of micropropagated plants to ex vitro conditions are indispensable to define which procedures should be used during the acclimatization phase. The objective of this research was to evaluate the presence of stomata and epicuticular wax on water loss control in micropropagated banana plants. For 24 days axillary buds were rooted in MS medium supplemented with NAA (1mg L-1) and agar (6g L-1), and afterwards the plantlets were acclimatized for 120 days. The treatments consisted of the evaluation of in vitro leaves and at different acclimatization stages, as follows: T1 - leaves of plants at the end of the in vitro rooting phase T2 - persistent leaves of plants after 30 days of acclimatization; T3 - new leaves from plants after 30 days of acclimatization (transition leaves); T4 - transition leaves from plants after 60 days of acclimatization; T5 and T6 - new leaves from plants after 60 and 120 days of acclimatization, respectively. Data regarding stomatal density, relative water content and presence of epicuticular wax were also evaluated. It was verified that new leaves from plants rooted in vitro under mixotrophic condition presented hight stomatal density and hence a reduced control of water loss. The reduced transpiration of leaves formed during the acclimatization phase can be attributed to the small number of stomata per unit of leaf area associated to the largest capacity of these in restricting water loss, and the presence of epicuticular wax.

Alterações anatômicas de bananeiras micropropagadas em resposta a aclimatização ex vitro

Researches about structural and physiological modifications in different stages of the micropropagation are fundamental to understand the effects of this technology to improve protocols and to reduce losses in the acclimatization. The objective of this study was to assess and to quantify the variations in the foliar anatomy of micropropagated banana plants during the ex vitro acclimatization in greenhouse. Thus, axillary buds from in vitro multiplication of Japira cultivar, were rooted in MS medium, added of NAA (1mg L-1) and agar (6g L-1), and kept at room temperature (25°C ±2°C) under 16 hours photoperiod and irradiation of 35µmol m-2 s-1, for 35 days. Subsequently, the plants were submitted to different acclimatization periods (zero, 21, 42, 63, 84 e 120 days) being the leaf anatomy of the plants evaluated by transversal and paradermal sections. A completely randomized design was used. The largest anatomical alterations it were verified after 42 days of the transplantation to ex vitro conditions, with pronounced thickness of chlorophyllian parenchyma and leaf blade, as well, as the differentiation of the majority of foliar tissues. The stomata were distributed on both sides of the leaves, with higher number on the undersurface and on leaves formed from in vitro foliar primordia.

Características físicas e nutricionais da matriz de encapsulamento na produção de sementes sintéticas de pimenta-longa (Piper hispidinervum C. DC.)

RESUMO – A pimenta-longa (Piper hispidinervum C. DC.) e um arbusto da familia Piperaceae, nativa da regiao amazonica, que vem despertando o interesse das industrias de cosmeticos e bioinseticidas pelo alto teor de safrol, oleo essencial extraido das folhas e talos. O objetivo do trabalho foi avaliar a influencia de caracteristicas fisicas e nutricionais da matriz de encapsulamento durante a producao de sementes sinteticas de pimenta-longa. Sementes germinadas de pimenta-longa foram utilizadas como material de encapsulamento. Em ambos os experimentos, a influencia da constituicao (agua ou meio Murashige e Skoog) e consistencia da capsula (alginato de sodio 1% ou 2%) e do tempo de complexacao (10, 20 e 30 min) em CaCl 2 , na abertura das capsulas, foi avaliada. Depois de encapsulados, os materiais foram transferidos para frascos com meio de MS e mantidos em sala de crescimento, onde, quinzenalmente, foi avaliada a taxa de emergencia e crescimento das plântulas encapsuladas. Verificou-se que o emprego de um endosperma artificial composto por 1% de alginato de sodio em meio de MS foi o tratamento que promoveu os melhores resultados para a emergencia e posterior crescimento de plântulas oriundas de sementes sinteticas aos 30 dias da semeadura em meio MS solido, independentemente do tempo de complexacao utilizado.

Somatic Embryogenesis in Açaí Palm (Euterpe oleracea Mart.)

The acai palm (Euterpe oleracea Mart.) is a species that belongs to the family Arecaceae and supplies one of the most popular “superfruits” of the Amazon rainforest, commonly known as “acai-do-para”. Due to the many health benefits, continuously elucidated by the scientific community, this species has become the target of several consumer markets around the globe. Due to the aforementioned benefits, the demand for products derived from E. oleracea, in Brazil and internationally, has increased over the last years, which requires a transition from an extractive production system to a system based on large commercially farmed areas. The acai palm (E. oleracea) can be propagated via seeds and via tillering. However, due to the low rates of production and survival of the plants obtained by tillers, commercial-scale production of plantlets is limited to sexual propagation, which presents drawbacks such as the slowness and unevenness of the germination process, aside from the resulting genetic heterogeneity. In this setting, in vitro cultivation techniques—especially somatic embryogenesis—are seen as a promising alternative to clonal propagation of E. oleracea. In the Euterpe genus, relatively few studies of somatic embryogenesis have been developed, limited to E. edulis and E. oleracea, the vast majority using zygotic embryos as initial explants. Immature inflorescences have also been studied as potential explants for palm trees, due to the high embryogenic capacity of the calli originating therefrom. In addition to the explants mentioned above, immature leaves are also seen as possible explants to be used in the initiation of the technique in E. oleracea. This chapter presents and discusses the principles, strategies and limitations of using somatic embryogenesis for the propagation of E. oleracea.

Anatomia foliar de cultivares de bananeira, influenciada por mudanças no ambiente de cultivo na fase de enraizamento/alongamento in vitro

Objetivou-se estudar a anatomia foliar de plantas de bananeira submetidas a alteracoes no ambiente de cultivo na fase de enraizamento in vitro .