Aparecida Gomes de Araujo

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.

Acclimatization and leaf anatomy of micropropagated fig plantlets

The survival of micropropagated plants during and after acclimatization is a limiting process to plant establishment. There is little information on how the anatomy of vegetative organs of Ficus carica can be affected by culture conditions and acclimatization. The present research aimed to study the effects of time on culture medium and substrates during the acclimatization of fig tree plantlets produced in vitro, characterizing some leaf anatomy aspects of plantlets cultured in vitro and of fig trees produced in field. Plantlets previously multiplied in vitro were separated and transferred into Wood Plant Medium (WPM) where they were kept for 0, 15, 30, 45 and 60 days. Different substrates were tested and studies on leaf anatomy were performed in order to compare among plantlets grown in vitro, plantlets under 20, 40 and 60 days of acclimatization, and field grown plants. Keeping plantlets for 30 days in WPM allowed better development in Plantmax during acclimatization. Field grown plants presented higher number of stomata, greater epicuticular wax thickness and greater leaf tissue production compared to in vitro ones. The leaf tissues of in vitro plantlets show little differentiation and have great stomata number compared with acclimatized plants, which reduce the number of stomata during the acclimatization process.

Fontes de silício na micropropagação de orquídea do grupo Cattleya

The purpose of this study was to determine the silicon source that provides better growth of Cattleya loddigesii orchid plants. Seedlings from seeds germinated in vitro with approximately 1.0 cm in length were inoculated in tubes containing 15 mL of modified Knudson C culture medium, added with sodium silicate (0, 5, 10 and 20 mg L -1 ) and potassium silicate (0, 5, 10 and 20 mL L -1 ), in all possible combinations. The culture medium had its pH adjusted to 5.8 ± 0.1 and solidified with 5 g L -1 of agar before the sterilization process at 121°C and 1 atm for 20 minutes. The cultures were maintained in a growth room with irradiance around 35 µmol m -2 s -1 , temperature of 25±1oC and photoperiod of 16 hours. The experimental design was completely randomized in a factorial scheme with 5 replications and 20 seedlings per treatment. Seedlings of C. loddigesii presented better growth (number of roots, length of the aerial part and of roots) in the modified Knudson C culture medium added with 5 mL L -1 of potassium silicate and 20 mg L -1 of sodium silicate. A larger number of shoots is observed with the addition of 5 mL L -1 potassium silicate in culture medium, in the absence of sodium silicate.

Concentrações de sais do meio Knudson C e de ácido giberélico no crescimento in vitro de plântulas de orquídea

The aim of this research was to test different concentrations of culture medium Knudson C and gibberellic acid in the in vitro growth of Hadrolaelia lobatta x Hadrolaelia purpurata Aco and Cattleya loddigesii plantlets. Seedlings deriving from in vitro germinated seeds with approximately 1,0cm length, were inoculated in bottles of 250cm3 containing 60mL of Knudson C culture medium at salts concentrations of 0; 50; 100 e 200%, and supplemented with 0; 2.5; 5; 7.5; 10mg L-1 of GA3. The cultures were maintained in growth room with a 35µmolm-2s-1 irradiance, 16 hours photoperiod and 25±1°C of temperature. After 90 days, it is observed that the culture medium Knudson C 200% for Cattleya loddigesii promote better in vitro growth. The addition of GA3 (2.5mg L-1) is efficient in the number of leaves increment. Better in vitro multiplication is registered in Knudson C medium in the original concentration (100%). For Hadrolaelia lobatta x Hadrolaelia purpurata Aco, the concentration of Knudson C culture medium influences the number of leaves (salts 200%) and sprouts (salts 50%), but does not have effect in the growth and biomass. No effect of the GA3 in number of sprouts, length of aerial part and fresh mass for the two genotypes was verified.

Fontes de nitrogênio, polpa de banana e ágar no desenvolvimento in vitro de plântulas de orquídea

Foram realizados dois experimentos com o objetivo de estudar os efeitos de fontes de nitrogenio, polpa de banana e agar no desenvolvimento in vitro de orquidea Cattleya loddigesii. O primeiro experimento constituiu-se de NH4NO3 (0; 25; 50; 75 e 100% da formulacao de 330 mg L-1) e KNO3 (0; 25; 50 e 100% da formulacao de 380 mg L-1) acrescidas ao meio MS. No segundo experimento, os tratamentos consistiram de concentracoes de agar (0; 2; 4; 6 e 8 g L-1), no meio de cultura Knudson C, acrescido de polpa de banana nanica (0; 50; 100; 150 e 200 g L-1) em todas as combinacoes possiveis. Apos a inoculacao as culturas foram mantidas em sala de crescimento com irradiância em torno de 35 μmol m-2 s-1, temperatura de 25±1oC e fotoperiodo de 16 horas, por 90 dias. Com base no peso da materia fresca das plântulas, numero de raizes, comprimento da parte aerea e comprimento da maior raiz, a adicao de 17,5 a 41,16% da formulacao original de NH4NO3 ao meio MS proporcionou melhor desenvolvimento in vitro em plântulas de Cattleya loddigesii. Maior numero de folhas foi obtido com a adicao ao meio MS de 100% da formulacao original de NH4NO3 e 50% de KNO3. A multiplicacao in vitro de plântulas de orquidea Cattleya loddigesii e viavel em meio Knudson C liquido com a utilizacao de 128,42 g L-1 de polpa de banana nanica.

Silicon sources in the micropropagation of the Cattleya group orchid

The purpose of this study was to determine the silicon source that provides better growth of Cattleya loddigesii orchid plants. Seedlings from seeds germinated in vitro with approximately 1.0 cm in length were inoculated in tubes containing 15 mL of modified Knudson C culture medium, added with sodium silicate (0, 5, 10 and 20 mg L -1 ) and potassium silicate (0, 5, 10 and 20 mL L -1 ), in all possible combinations. The culture medium had its pH adjusted to 5.8 ± 0.1 and solidified with 5 g L -1 of agar before the sterilization process at 121°C and 1 atm for 20 minutes. The cultures were maintained in a growth room with irradiance around 35 µmol m -2 s -1 , temperature of 25±1oC and photoperiod of 16 hours. The experimental design was completely randomized in a factorial scheme with 5 replications and 20 seedlings per treatment. Seedlings of C. loddigesii presented better growth (number of roots, length of the aerial part and of roots) in the modified Knudson C culture medium added with 5 mL L -1 of potassium silicate and 20 mg L -1 of sodium silicate. A larger number of shoots is observed with the addition of 5 mL L -1 potassium silicate in culture medium, in the absence of sodium silicate.

Propagação in vitro de orquídea: iodeto de potássio e cloreto de cobalto em meio de cultura Knudson C

Objetivou-se determinar modificacoes ao meio de cultura Knudson C, acrescendo-o de iodeto de potassio e cloreto de cobalto, para que proporcione maior crescimento em plântulas de Cattleya loddigesii. Plântulas de orquidea, oriundas de sementes germinadas in vitro, com, aproximadamente, 1,0 cm de comprimento, foram inoculadas em tubos de ensaio contendo 15 mL de meio de cultura Knudson C modificado, acrescido de iodeto de potassio (0; 0,45; 0,9 e 1,35 mg.L-1) e cloreto de cobalto (0; 0,015; 0,030 e 0,045 mg.L-1), em todas as combinacoes possiveis. O meio de cultura teve seu pH ajustado para 5,8 ± 0,1 e foi solidificado com 5 g.L-1 de agar antes da autoclavagem a 121oC e 1 atm por 20 minutos. Apos a inoculacao os tratamentos foram mantidos em sala de crescimento com irradiância de 35 µmol.m-2.s-1, temperatura de 25 ± 1oC e fotoperiodo de 16 horas. Ao final de 120 dias, foram avaliados numero de raizes, comprimento medio de raizes e da parte aerea e massa de materia fresca de plântulas. O cloreto de cobalto, em sua maior concentracao (0,045 mg L-1), adicionado ao meio Knudson C modificado, sem a suplementacao de iodeto de potassio, proporciona melhores resultados quanto ao crescimento in vitro das plântulas de Cattleya loddigesii.

Fontes de silício na micropropagação de orquídea do grupo Cattleya - doi: 10.4025/actasciagron.v33i3.6281

The purpose of this study was to determine the silicon source that provides better growth of Cattleya loddigesii orchid plants. Seedlings from seeds germinated in vitro with approximately 1.0 cm in length were inoculated in tubes containing 15 mL of modified Knudson C culture medium, added with sodium silicate (0, 5, 10 and 20 mg L -1 ) and potassium silicate (0, 5, 10 and 20 mL L -1 ), in all possible combinations. The culture medium had its pH adjusted to 5.8 ± 0.1 and solidified with 5 g L -1 of agar before the sterilization process at 121°C and 1 atm for 20 minutes. The cultures were maintained in a growth room with irradiance around 35 µmol m -2 s -1 , temperature of 25±1oC and photoperiod of 16 hours. The experimental design was completely randomized in a factorial scheme with 5 replications and 20 seedlings per treatment. Seedlings of C. loddigesii presented better growth (number of roots, length of the aerial part and of roots) in the modified Knudson C culture medium added with 5 mL L -1 of potassium silicate and 20 mg L -1 of sodium silicate. A larger number of shoots is observed with the addition of 5 mL L -1 potassium silicate in culture medium, in the absence of sodium silicate.