Jackeline Schultz Soares

Cultivo in vitro de Dendrobium nobile com uso de água de coco no meio de cultura

A agua de coco e um dos componentes orgânicos de baixo custo mais utilizados nos meios de cultura para cultivo in vitro de plantas, mas poucas sao as informacoes sobre seus efeitos em orquideas, onde esse tipo de propagacao e utilizado. Assim, objetivou-se estudar as quantidades de agua de coco acrescidas ao meio de cultura quanto aos seus efeitos na germinacao e crescimento in vitro de Dendrobium nobile. Foi utilizado o delineamento experimental inteiramente casualizado, com tres repeticoes, e os tratamentos compostos de cinco volumes de agua de coco (0; 50; 100; 150 e 200 mL L-1), que foram adicionados ao meio de cultura. Foram utilizadas como material de estudo sementes de D. nobile produzidas mediante autopolinizacao manual. Apos a semeadura, as culturas permaneceram por seis meses em sala de crescimento com temperatura e fotoperiodo controlados (12 horas, 1000 lux; 23oC ± 2) quando as plântulas foram avaliadas. A adicao de 200 mL L-1 de agua de coco ao meio de cultura propiciou os melhores resultados para comprimento, diâmetro e numero dos pseudobulbos, numero de folhas, numero de raizes, comprimento de raizes e massa fresca de D. nobile, nao influenciando apenas a porcentagem de germinacao e o numero de plântulas produzidas.

Germinação assimbiótica e desenvolvimento de Dendrobium nobile Lindl. sob efeito de reguladores vegetais no tratamento pré-germinativo

O presente trabalho teve como objetivo estudar a influencia dos reguladores vegetais BAP e GA3 como tratamentos pre-germinativos no processo de germinacao e desenvolvimento inicial de plântulas de Dendrobium nobile, especie importante pelas propriedades farmacologicas como anti-oxidante, vasodilatadora e ate mesmo anti-cancerigena, alem do valor ornamental. Os tratamentos pre-germinativos consistiram de BAP e GA3, separadamente, nas concentracoes de 0,0; 1,0; 2,0 e 5,0 mg L-1. Apos seis meses da semeadura in vitro e manutencao em câmara de germinacao e de crescimento com temperatura e foto-periodo controlados (12 horas e 23oC ± 2), foram avaliados os parâmetros numero de sementes germinadas, porcentagem de germinacao, massa fresca e altura das plântulas, diâmetro e numero de pseudobulbos, numero de folhas, numero de raizes, e o comprimento da maior raiz. O delineamento experimental foi inteiramente casualizado. Todas as variaveis foram submetidas a analise de variância e de regressao, quando significativas. As sementes de D. nobile germinaram melhor na ausencia de reguladores vegetais e os tratamentos com BAP ou GA3 na embebicao das sementes pouco beneficiaram o desenvolvimento in vitro de D. nobile.

Luminosidade e imersão em água na aclimatização intermediária de Dendrobium phalaenopsis

Dendrobium phalaenopsis is an ornamental orchid that presents good germination and development in asymbiotic culture medium. However its ex vitro adaptation still requires studies, since the dehydration of seedlings may delay its growth and development. This study aimed to investigate the effects of the water immersion and two luminosity conditions in the intermediate acclimatization of D. phalaenopsis. Plants were divided into sets of 40, and immersed in distilled water during 0, 12, 24, 36, 48, 60, 72 or 84 hours. After each immersion period the plants were transferred to containers and allocated inside a growth room for intermediate acclimatization during 30 days. A set of 20 plants from each period of immersion and from the control remained under white fluorescent light (18.9 µmol/m2/s) and the other 20 plants remained under white fluorescent light + red fluorescent light (14.85 µmol/m2/s). Plants were acclimatized in a greenhouse (162.0 µmol/m2/s) for 10 months. As immersion time increased, a decrease in fresh weight and length of pseudobulbs relation occurred, as well as in the number of roots of the plants grown under white light + red light. On the other hand, plants grown under white light did not respond to immersion time. Immersion in distilled water, regardless of light conditions, is not recommended for D. phalaenopsis.

APLICAÇÃO FOLIAR DE GA3 NO CRESCIMENTO E DESENVOLVIMENTO DE Passiflora edulis Sims f. flavicarpa Degener

With the knowledge that the exogenous application of gibberellins can alter physiological processes modifying the growth and development of plants as they function asregulator of cell division and elongation, the aim of this study was to evaluate the growth and development of Passiflora edulis Sims f. flavicarpa Degener grown under light of 650 µmol m-2 s-1 for nine months andsubjected to weekly sprays with GA3. The experimental design was completely randomized with five treatments (0.0, 1.5, 3.0, 15.0 and 30.0 mg L-1 GA3) and ten repetitions. The substrate used was composed of a mixture (1:1:1 by volume) of washed coarse sand, chaff of washed coal and dystroferric red latosol organized in pots with a capacity of 5L. The concentrations of GA3 influenced (p<0.05) most of the variables except the length of the main stem to the insertion of the first lateral stem, the number of lateral stems, the number of nodes of the main stem to the insertion of the first stem side, the number of nodes of the main stem to the insertion of the first tendril and the first three-lobed leaf, at the beginning of flowering, the number of lateral stems issued by the plant at the beginning of flowering and the number of nodes from the base of the main stem up the insertion of the first flower buds. Concentration of around 15 mg L-1 caused higher plant length, greater length, greater number of nodes of the plant, and higher fresh and dry weight of plants. The use of 30 mg L-1 GA3 anticipated the issuance of the first tendril and the first three-lobed leaf and produced a greater number of flower buds. Exogenous use of GA3 at concentrations of 30 mg L-1 was more effective in inducing floral that the evocation of Passiflora edulis Sims f. flavicarpa Degener.

Cultivation period, lighting conditions and BAP concentrations on in vitro induction shoots of Dendrobium phalaenopsis Deang Suree.

The technique of in vitro micropropagation allows the production of large amounts of plants. However, some aspects of the orchid’s in vitro micropropagation are still poorly studied. This study analyzed the lighting conditions, time of cultivation and BAP concentrations on in vitro budburst of Dendrobium phalaenopsis Deang Suree. Therefore, a quantitative analysis of biometric parameters of plants grown during 90 and 180 days on ½ MS medium under different lighting conditions (18.90 mol m-2 s-1, 14.85 mol m-2 s-1, 9.45 mol m-2 s-1) and concentrations of BAP (0; 0.5; 1; 1.5; 2; 2.5 e 3 mg L-1). The best results of budburst were obtained during 180 days, under white fluorescent light (18.90 mol m-2 s-1) and using 1.5±0.1 mg L-1 of BAP.

Growth and development of Hemerocallis fulva subjected to doses of nitrogen and phosphorus

The objective was to evaluate the effect of different doses of nitrogen and phosphorus on growth and development of Hemerocallis fulva variety Flore Full, herbaceous perennial widely used in landscaping. The experimental design was randomized blocks with 25 treatments, arranged in a factorial 5 x 5 (0; 75; 150; 225 and 300 kg ha-1 N and 0, 100, 200, 300 and 400 kg ha-1 P), with 4 replicates. The phosphorus fertilization was carried out 15 days after planting (DAP) and nitrogen was applied in coverage divided in three equal applications at 15, 120 and 240 DAP. There were evaluated the plant height, number of tillers per plant, soil coverage area, the fresh mass of plant, root system and shoot; and the dry mass of plant, root system and aerial part, and calculated the ratio of root dry mass and plant dry mass. It was also obtained the nutrient content of the leaf tissue and root system. The highest tillering was gained with the use of 150 kg ha-1 N combined with 400 kg ha-1 of P. Intermediate doses of N (75-170 kg ha-1 of N) showed higher production of plant fresh and dry mass and root dry mass. Doses of N and P influenced the N and P content in plant tissues of roots and leaves of Hemerocallis. Plants fertilized with 300 kg ha-1 of N and 273 kg ha -1 of P lead to the highest levels of N in the leaves and doses of 80 kg ha-1 of N and 68 kg ha-1 P, the highest content of P in the leaves of H. fulva. Already, in the roots, the highest N content was obtained with application of 300 kg ha-1 N in the presence of P and doses of 225 kg N ha-1 combined with 300 ha-1 P provided the highest P content in the roots

Aclimatização de Brassavola tuberculata com a utilização de ANA em diferentes substratos

One of the most limiting factors of orchid in vitro culture is the acclimatization. Thus the aim of this study was to evaluate the survival and initial growth of the Brassavola tuberculata (Orchidaceae) using naphthalene acetic acid (NAA), and different substrates during acclimatization. Plants were obtained from in vitro culture, previously immersed for 10 seconds in NAA solutions (0.0; 0.5; 1.0; 1.5; 2.0; 2.5; 3.0; 4.0 or 4.5 mg/L), and planted in plastic containers containing as substrate sphagnum, coconut fiber or a mix of sphagnum + coconut fiber 1:1 (v:v). The experiment was carried out in a completely randomized design, and the treatments were arranged in factorial 3x10, three substrates and 10 NAA concentrations, with 10 replications of one plant. After staying for 210 days in the greenhouse (83 µmol/m2/s) the plants were evaluated according to their survival, number of leaves, roots and offshoots, the length of the longest leaf and the longest root, fresh and dry mass of shoot and root. Increments of these variables in relation to the observed values during planting were also calculated. The substrates were evaluated according to their porosity, maximum water retention, substrate density, real density, electric conductivity and pH. The highest survival (67.7%) was obtained using the calculated concentration of 1.8 mg/L NAA which promotes the formation of efficient root system for the development of the species. The sphagnum is the most suitable substrate for the survival and early growth of B. tuberculata, in acclimatization phase.

LUMINOSITY AND WATER IMMERSION IN THE INTERMEDIATE ACCLIMATIZATION FOR Dendrobium phalaenopsis Deang Suree

Dendrobium phalaenopsis Deang Suree has good germination and development in asymbiotic culture medium, however his ex vitro adaptation still requires studies, because it causes dehydration of plants, delay their growth and development. The objective of this work was to study the combined effect of the immersion time in distilled water plant and two luminosity conditions in the treatment of intermediate acclimatization to D. phalaenopsis . Plants were divided into sets of 40, being subjected to immersion for 0, 12, 24, 36, 48, 60, 72 or 84 hours. After each immersion period the plants were transferred for containers containing the substrate planting and later allocated in growth room for intermediate acclimatization for 30 days. A set of 20 plants from each period of immersion and from the control remained under white fluorescent light (18.9 µmol m -2 s -1 ) and the other 20 plants remained under white fluorescent light + red fluorescent light (14.85 µmol m -2 s -1 ). After this period, the plants were subjected to acclimatization in greenhouse for 10 months. While immersion time increased the increments of fresh weight, pseudobulbs number and the roots number of plants grown under white light + red light decreased, while plants grown under white light did not show response with respect to immersion time. Absence of immersion in distilled water independently of luminosity condition is beneficial to plants of D. phalaenopsis Deang Suree.