RESUMO A técnica do estiolamento é muito utilizada na micropropagação de várias espécies de plantas. Este trabalho teve como objetivo avaliar o crescimento e desenvolvimento de brotos de Cattleya labiata in vitro em função de reguladores de crescimento e da presença e ausência de luz. Segmentos caulinares, com aproximadamente + 1,0 cm de altura, foram inoculados em tubos de ensaio contendo 15,0 mL de meio de cultura MS, acrescido de diferentes concentrações de BAP (0,0; 2,0 e 4,0 mg L-1), ANA (0,0; 1,0 e 2,0 mg L-1) e ambientes de cultivo (sala de crescimento no escuro e com fotoperíodo 16 horas) em delineamento inteiramente casualizado. Aos 150 dias, avaliou-se: a) número de brotos estiolados; b) número de nós por broto estiolado; c) comprimento do segmento caulinar (cm); d) número de raízes; e, e) massa seca total da plântula (g). As maiores médias foram obtidas com a utilização de 4,0 mg L-1 de BAP e 1,0 mg L-1 de ANA para número de brotos estiolados e de 2,0 mg L-1 de ANA para número de nós por broto estiolado, em ausência de luz. O comprimento do segmento caulinar foi superior em ambiente sob ausência de luz; em contraste, o número de raízes e a massa seca total da plântula foram superiores em ambiente luminoso, independente do regulador de crescimento adicionado ao meio de cultivo. O estiolamento de segmentos caulinares é uma técnica viável, visto que proporcionou características vantajosas para a fase de multiplicação in vitro da referida espécie.

ABSTRACT The technique of etiolation is widely used in the micropropagation of various plant species. The aim of this study was to evaluate growth and development in shoots of Cattleya labiata grown in vitro, as a function of growth regulators and the presence and absence of light. Stem segments, approximately ± 1.0 cm in height, were inoculated in test tubes containing 15.0 mL of MS culture medium supplemented with different concentrations of BAP (0.0, 2.0 and 4.0 mg L-1) and NAA (0.0, 1.0 and 2.0 mg L-1), and in different growth environments (growth room, darkness and a photoperiod of 16 hours) in a completely randomised design. At 150 days, the following were evaluated: a) number of etiolated shoots; b) number of nodes per etiolated shoot; c) length of stem segment (cm); d) number of roots; and e) total seedling dry weight (g). The highest mean values were achieved with the use of 4.0 mg L-1 BAP and 1.0 mg L-1 NAA for the number of etiolated shoots, and 2.0 mg L-1 NAA for the number of nodes per etiolated shoot in the absence of light. The length of stem segment was greater in the absence of light; in contrast, the number of roots and the total seedling dry weight were greater in a bright environment, irrespective of the growth regulator added to the culture medium. The etiolation of stem segments is a viable technique, as it provides features that are advantageous in the in vitro multiplication stage of the species.

ABSTRACT The aim of this study was to evaluate the development of Chinguensai (Brassica pekinensis L.) seedlings, under different formulations of substrates and sizes of containers, in Fortaleza, Ceará. For this, two studies were conducted in factorial design with randomized blocks and four replicates. The first study was conducted in a factorial (4 × 4) design. Four substrate formulations (powder-type coconut fiber; carbonized rice hull and earthworm casting) had the following proportions: S1 (1:1:1); S2 (0:1:1); S3 (1:0:1); and S4 (0:0:1) by volume basis (v/v) and four evaluation dates (22, 27, 34 and 41 days after sowing — DAS). The second study was conducted in a factorial (3 × 4) design with three types of containers with different cell volumes (31, 18 and 11 cm3) and four evaluation dates (22, 27, 34 and 41 DAS). The fresh and dry weight of the shoot and root systems was evaluated. Both studies showed no interaction between the variables, with differences noted for substrate factors, containers and times in all traits. In the first study, the earthworm compost resulted in the highest yield of fresh and dry seedling weight. In the second study, the container with 31 cm3 of cell volume showed the highest production of fresh and dry weights. The results showed that the substrate composed solely of earthworm humus and with the use of trays with 31 cm3 of cell volume provided seedlings of Chinguensai with the optimal production for transplanting 41 DAS.

RESUMO A bromélia Encholirium spectabile Martius ex Schultes f. é uma espécie endêmica da Caatinga. O objetivo deste trabalho foi avaliar a eficiência de soluções crioprotetoras em sementes de bromélia. Os tratamentos consistiram da imersão das sementes em soluções crioprotetoras e de vitrificação, antes da imersão em nitrogênio líquido (NL) (-196 ºC), conforme os tratamentos a seguir: T1 - controle: sem crioprotetores; T2 - glicerol 2M (20 min) + PVS2 (10 min); T3 - glicerol 2M (20 min) + PVS2 com floroglucinol a 1% (10 min); T4 - sacarose 0,4M (20 min) + PVS2 (10 min); T5 - sacarose 0,4M (20 min) + PVS2 com floroglucinol a 1% (10 min); T6 - glicerol 2M (20 min) + sacarose 0,4M (20 min) + PVS2 (10 min); T7 - glicerol 2M (20 min) + sacarose 0,4M (20 min) + PVS2 com 1% de floroglucinol (10 min). O delineamento experimental foi o inteiramente casualizado com sete tratamentos e cinco repetições. Os dados foram submetidos à análise de variância (ANOVA) e as médias comparadas pelo teste de Tukey a 5%. O grau de umidade das sementes no início do experimento foi de 8,4%. Não apresentaram diferença estatística significativa para as variáveis porcentagem de sementes germinadas e comprimento de plântula, porém, para a variável massa seca de plântula, o tratamento T3 apresentou valor estatisticamente superior aos tratamentos T1, T4, T5 e T6, mas não diferiu dos demais tratamentos. Para a criopreservação de sementes da bromélia Encholirium spectabile não é necessário a utilização de soluções crioprotetoras.

ABSTRACT The bromeliad Encholirium spectabile Martius ex Schultes f. is a endemic species of the Caatinga. The aim of this study was to evaluate the efficiencies of cryoprotectant in bromeliad seeds. The treatments consisted of immersing seeds in different cryoprotectant solutions and vitrification solutions before immersion in liquid nitrogen (NL) at -196 °C, as the following treatments: T1- Control: without cryoprotectants; T2- glycerol 2M (20 min) + PVS2 (10 min), T3- glycerol 2M (20 min) + PVS2 with phloroglucinol 1% (10 min), T4- sucrose 0.4M (20 min) + PVS2 (10 min); T5- sucrose 0.4M (20 min) + PVS2 with phloroglucinol 1% (10 min); T6- glycerol 2M (20 min) + sucrose 0.4M (20 min) + PVS2 (10 min), T7- glycerol 2M (20 min) + sucrose 0.4M (20 min) + PVS2 with phloroglucinol 1% (10 min). The experimental design was a completely randomized design with seven treatments and five replicates per treatment. Data were subjected to analysis of variance (ANOVA) and means were compared by the Tukey test at 5%. The seed moisture at the beginning of the experiment was 8.4%. There were statistically significant for the variables percentage of seeds germinated and seedling length, but for the variable seedling dry weight, T3 treatment was presented a value statistically high to T1, T4, T5 and T6, but did not differ from T2 and T7 treatments. It is concluded that for the cryopreservation of seeds of Encholirium spectabile is not necessary to use cryoprotectant solutions.

Objetivou-se neste trabalho estudar a influência de diferentes concentrações de sacarose no crescimento in vitro de Caularthron bicornutum (Hook.) Raf. O experimento foi conduzido no Departamento de Tecnologia da Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista - Unesp/FCAV, em Jaboticabal, São Paulo (SP), no período de janeiro a outubro de 2009. O delineamento experimental foi inteiramente casualizado. Foram seis tratamentos (cinco concentrações de sacarose: 10; 20; 30; 40 e 50g L-1 e ausência de sacarose no meio de cultura) e cinco repetições, totalizando 30 parcelas e 12 plântulas/parcela. A semeadura foi feita em meio de cultura MS e, após 90 dias, estas foram selecionadas e transferidas para frascos contendo meio de cultura com metade da concentração de macronutrientes (½ MS), com as diferentes concentrações de sacarose. Aos 150 dias após a semeadura, foi realizado o segundo subcultivo, cujos procedimentos foram semelhantes aos do primeiro, sendo as plântulas reinoculadas para renovação do meio. Após 210 dias da semeadura, foi realizada avaliação. Verificou-se que a sacarose não influenciou a porcentagem de enraizamento, porém foi efetiva no número e crescimento de raízes e da parte aérea de plântulas de Caularthron bicornutum, em concentrações que variaram de 13 a 29g L-1 de sacarose.

This research aimed to studied the influence of different sucrose concentrations in the in vitro growth of Caularthron bicornutum (Hook.) Raf.. The experiment was conducted at Department of Technology of Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista - Unesp/FCAV, Jaboticabal, São Paulo state, in the period of January to October of 2009. Were studied 6 treatments (5 sucrose concentrations: 10; 20; 30; 40 and 50g L-1 and sucrose absence in the middle of culture) and 5 replications with 12 seedlings per replication had been used in a completely randomized design. The seeds were placed in culture medium MS, and after 90 and 150 days they were selected and transferred for flasks containing culture medium ½MS, with the different sucrose concentrations. After 210 days evaluation was accomplished. It was verified that the sucrose in the concentrations from 13 to 29g L-1 provided the largest averages for the number of roots, length of roots and length of the aerial part; however it didn't influence in the rooting percentage of the plântlests of Caularthron bicornutum.