Claudinéia Ferreira Nunes

Diferentes suplementos no cultivo in vitro de embriões de pinhão-manso

The objective of this work was to evaluate the influence of maturation stages of physic nut fruits on the development of their embryos cultivated in MS medium supplemented with sucrose, coconut water and activated carbon. Fruits were collected, and their embryos were extracted aseptically. They were submitted to two experimental conditions: embryos from fruits in three development stages (immature, mature and dry) were put into MS medium, supplemented with sucrose (0, 15, 30 and 60 g L-1); embryos derived from dry fruits were put into MS medium supplemented with sucrose 30 g L-1, activated carbon (0, 1, 2 and 3 g L-1), and coconut water (0, 50, 100, 150, 200 e 250 mL L-1). Explants were kept in a growth chamber under controlled conditions during 30 days. Only the zygotic embryos from immature fruits needed sucrose supplementation in the culture medium to sustain germination. Better embryos development occurs in MS medium supplemented with 60 g L-1 of sucrose. The association of activated carbon and coconut water provides better growth of seedlings derived from embryos extracted from seeds of dry fruits.

Características anatômicas de mudas de morangueiro micropropagadas com diferentes fontes de silício

O objetivo deste trabalho foi avaliar o efeito de diferentes fontes de silicio, utilizadas na micropropagacao, nas caracteristicas anatomicas de mudas de morangueiro (Fragaria x ananassa). Foram utilizados propagulos da cv. Oso Grande cultivados em meio Murashige e Skoog (MS), acrescido de 30 gL-1 de sacarose, 6 gL-1 de agar e 1 mgL-1 de 6-benzilaminopurina. Os tratamentos consistiram da adicao ao meio MS dos silicatos de calcio, de sodio e de potassio, na dosagem de 1 gL-1. O tratamento testemunha foi o meio MS sem fonte de silicio. Odelineamento experimental foi o inteiramente ao acaso, com dez repeticoes. Os propagulos foram mantidos por 45 dias em sala de crescimento, em condicoes controladas. Avaliaram-se caracteristicas fitotecnicas e anatomicas dos propagulos in vitro. Verificou-se que o aumento da massa de materia fresca e seca dos propagulos de morangueiro ocorreu na presenca de silicato de sodio. Asuplementacao do meio de cultura com silicio proporcionou maior teor de clorofila. Aadicao de silicato de sodio ao meio MS resultou em aumento da espessura dos tecidos do limbo foliar e da deposicao de cera epicuticular e na formacao de deposito de silicio nas celulas.

Morfologia externa de frutos, sementes e plântulas de pinhão-manso

O objetivo deste trabalho foi caracterizar aspectos morfologicos externos do fruto, semente, processo germinativo e plântula de Jatropha curcas. Em frutos e sementes foram avaliadas as caracteristicas: dimensoes, tipo, cor, textura, deiscencia e numero de sementes por fruto, presenca de caruncula, formato do embriao e presenca do endosperma. No estudo do desenvolvimento pos-seminal e diferenciacao das plântulas, as sementes foram colocadas para germinar em meio de cultura MS (Murashige & Skoog). O fruto de Jatropha curcas e seco deiscente, capsular, tricoca, geralmente com tres sementes e endocarpo lenhoso. A semente e ovalada, endospermica, com envoltorio liso e presenca de caruncula. O embriao possui um par de cotiledones e eixo hipocotilo-radicula cilindrico e reto. A germinacao e epigea.

Cytological characterization of Jatropha curcas callus in different periods of cultivation

The aimed was characterization and determining the time for Jatropha curcas callus subculture. The pattern of J. curcas callus development is sigmoidal with 5 distinct phases, and transplantation should be performed at the end of the deceleration phase (approximately day 28). During callus development, it was observed that at the onset of growth in the exponential phase the cells were internally disorganized; in the linear phase, respiratory metabolism was resumed through reorganization of the first mitochondria; and by the mid-deceleration phase, the cells were entirely active, and several organelles were detected. This organizational status was maintained throughout the stationary phase during which somatic pre-embryos were identified. At the end of the stationary phase, intracellular disruption began, and the cells entered senescence, which characterized the decline phase for the J. curcas calli growth curve.

Análise bioquímica de calos de pinhão-manso

The physic nut (Jatropha curcas L.) is gaining importance because of its potential as raw material for biodiesel. Studies aiming the adequacy of agronomic techniques and tissue culture contribute, indirectly, to this aspect, helping applied research as biotechnology, in situations that aim plant regeneration. Therefore, it is essential to evaluate, the behavior of primary metabolites during the callus growing season. The callus mass at the inoculation time showed no carbohydrates reserve. At the 42nd day the sucrose absorption started in the medium, while the accumulation in the explant occurred from the 98th day of cultivation. Amino acid content was high at the inoculations day and around the 98th day, both amino acids and protein levels decreased.