Francyane Tavares Braga

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.

Luz natural e concentrações de sacarose no cultivo in vitro de Cattleya walkeriana

Cattleya walkeriana e uma das mais apreciadas orquideas do mundo, possuindo grande valor ornamental. A micropropagacao e uma importante ferramenta para reproducao dessa especie. Pelos altos custos de producao atraves da micropropagacao convencional, relacionados a perdas durante aclimatizacao e alto consumo de energia em salas de crescimento, objetivou-se com este trabalho avaliar estrategias alternativas no cultivo in vitro. Foram testados dois diferentes fatores, sendo eles luz (em sala de crescimento convencional, casa de vegetacao com sombreamento de 50%, e casa de vegetacao sem sombreamento) e concentracoes de sacarose (0, 15 e 30 g.L-1). O material se constitui de plântulas previamente germinadas in vitro, em meio MS e cultivadas em sala de crescimento por 90 dias. Luz natural em casa de vegetacao, resultou em aumento no numero de brotos, na espessura foliar e na frequencia e diâmetro dos estomatos, e ocasionou diminuicao do comprimento das plântulas e dos teores de clorofila. Um menor numero de raizes e brotacoes foram formados na concentracao de 15 g.L-1 de sacarose. A ausencia de sacarose resultou em menores teores de clorofila. Pela analise dos resultados, foi possivel concluir que o ambiente de cultivo altera as respostas de plântulas cultivadas in vitro e pode-se recomendar o uso da luz natural e reducao nas concentracoes de sacarose pela metade para a micropropagacao de Cattleya walkeriana, observando-se a fase da propagacao e os objetivos da mesma.

Qualidade de luz no cultivo in vitro de Dendranthema grandiflorum cv. Rage: características morfofisiológicas

In micropropagation, the maintenance of the growth rooms is labor-consuming and expensive, which increases the necessity of studies involving the manipulation and control of the culture conditions to optimize the in vitro growth. The quality of light may modify the morphogenesis of the plants through many processes mediated by receivers, which absorb the light in the blue and red region of the spectrum, being therefore, a viable way to increase the quality of the micropopagated plants. This work aimed at evaluating the effect of the spectral alteration under conditions of natural light on the morphophysiology of micropropagated chrysanthemum [Dendranthema grandiflorum (Ramat.) Kitam] plants. Nodal segments with one bud cultivated in vitro were used as explants. The medium used was MS with half of its salts concentration supplemented with 15g.L-1 sucrose. The incubation conditions were growth room (GR), this being the control treatment, greenhouse (GH) without shadow protection and greenhouse with 50% shadow in the colors black, blue, and red. The evaluation was done 60 days after the implantation of the assay. For the leaf number, GR showed to be the most effective incubation form, with a higher number of leafs. The same occurred with the number of roots and shoots and the average length of roots. For the aerial part length, GR and GH with shadow protection in all three colors were more efficient. Considering the anatomical aspects for stomatal density, a greater number of stomatal/mm2 was observed in GH without shadow protection and in GH with red shadow protection. For the polar and equatorial diameters of the stomata, GR without shadow protection, followed by GR with shadow protection in the colors blue and red, presented a bigger stomatal diameter. With the presented results, it is possible to recommend the use of natural light for the in vitro cultivation of chrysanthemum, however, the manipulation of the spectral quality is not recommended.

Características morfofisiológicas de abacaxizeiro 'gomo de mel' enraizado in vitro sob luz natural e substrato vermiculita

ABSTRACT – This study aimed to evaluate the effect of vermiculite, agar, artificial light and natural light in the in vitro rooting of pineapple shoots ‘Gomo de Mel’ propagules, as well as, to characterize these plants anatomically. The study was performed at the Plant Tissue Culture Laboratory of the Department of Agriculture - UFLA, Lavras-MG. It was used shoots with 2 cm of length cultivated in MS medium added with 30g.L -1 of sucrose. Two physical supports were tested: 6g.L -1 of agar and 15 g.L -1 of vermiculite for the shoot rooting in two environments: growth room 25±1 oC, 45 W.m -2 .s -1 during 16 hours and greenhouse with radiation of 115,08 W.m -2 .s -1 and 33 oC (natural light). After 60 days, it was evaluated the aerial part length, fresh and dry mass of aerial part and roots, the thicknesses of foliar limb tissues, besides the number, polar and equatorial diameter of the stomata. The experiment was installed in a completely randomized design. The results showed significance in the interaction between physical supports and environment for all analyzed variables. The use of the vermiculite substrate in artificial light presented better results in all variables, ex-cept for number of stomata. For the anatomical characteristics, bigger thicknesses of the foliar limb tissues was verified when it was used vermiculite and natural light, being that, for the agar use, it also increased the thicknesses only when the environment of natural light was used. Regarding the number of stomata/mm

Viabilidade e germinação de embriões de oliveira submetidos a diferentes condições de armazenamento de frutos

The objective of this work was to evaluate the effect of different storage conditions on the preservation of the viability and germination of olive zygotic embryos. A completely randomized block design was used, in a 4x2 factorial arrangement. Fruits of the cultivar Santa Catalina were subjected to different storage conditions - plastic bag in refrigerator at 4-5oC and 15% relative humidity (RH), dissector in refrigerator at 4-5oC and 12% RH, plastic bag at laboratory room at 27±1oC and 55% RH, dissector in laboratory room at 27±1oC and 30% RH -, and to storage periods of 30 and 120 days. In vitro germination and viability were evaluated by the tetrazolium test at 30 and 120 days of storage. The highest germination rate (91.66%) and viability (33.33%) were observed at 4-5oC and 12% RH at 30 days. This storage condition preserves olive fruits for longer time.

Outcrossing rate in olive assessed by microsatellite and inter simple sequence repeat (ISSR) markers

Olive is known to be an allogamous species. The aim of this study was to estimate the magnitude of cross-pollination rate using microsatellite simple sequence repeats (SSR) and inter simple sequence repeats (ISSR) molecular markers in olive genotypes. The DNA from maternal plants and 23 progenies of two different accessions, Ascolano USA and MGS GRAP541 were extracted and screened with two microsatellite and ten ISSR markers. The outcrossing rate and other related parameters were analyzed using the MLTR application. The set of estimates, individually and collectively, support the hypothesis of frequent allogamy in both olive genotypes evaluated, with high rates of outcrossing in both markers. Keywords: Olea europaea L., outcrossing rate, zygotic embryos, mating system, molecular markers

Effect of coconut water on growth of olive embryos cultured in vitro

The experiment was carried out to determine the appropriate dose of coconut water as supplement for in vitro cultivation of zygotic embryos from 19 olive genotypes. The isolated embryos of the olive seeds were immersed on culture medium containing 0 (control), 25, 50, and 100mL L-1 of fresh and sterile coconut water and kept for 45 days under controlled environment. The percentage of germination, shoot length, number of roots, number of leaves and number of internodes were measured for all 19 olive genotypes. The ANOVA of the parameters evaluated showed significant genotypes x doses of coconut water interaction for shoot length, number of leaves and number of internodes and the dose of 100mL L-1 produced the best results overall as indicated by the means of measured parameters. However, the study showed the importance of determining the appropriate dose of coconut water for each genotype under consideration as shown by significant genotype x dose of coconut water interaction effect.

In vitro Plantlets Regeneration from Nodal Segments of Murici (Byrsonima gardneriana)

This study aimed to develop efficient protocols for the in vitro micropropagation of Byrsonima gardneriana . Nodal segments were obtained from seedlings germinated in vitro with 60 days of life. These were inoculated in MS/2 supplemented with 87.64 µM of sucrose and solidified with 0.7% of agar, supplemented with different concentrations of cytokinin 6-benzylaminopurine (0.0; 2.0; 4.0 and 8.0 µM) associated with different concentrations of auxin, indole acetic acid (0.0; 0.5 and 1.0 µM) and naphthaleneacetic acid (0.0; 0.5 and 1.0 µM). The sprouting were individualized and transferred to MS/2 cultures with different concentrations of indole butyric acid (0.0; 1.0; 2.0 and 3.0 µM), and presence and absence of activated charcoal (1.0 g L -1 ). The use of concentrations from 2.0 to 4.0 µM 6-benzylaminopurine was efficient in the multiplication of B. gardneriana , given that, using concentrations above these, a decrease in this efficiency occurs. The use of auxin interfered negatively with the results. In vitro rooting occurs even in medium free of auxin. The activated charcoal was insufficient for rooting. The use of growth regulators 6-benzylaminopurine and indole butyric acid are efficient in micropropagation of B. gardneriana , however, further studies should be performed to optimize this protocol.

Pre-germination Treatments, Quality of Light and Temperature on Syagrus coronata (Mart.) Becc. Seeds Germination

Studies show that most species of palm trees present seed dormancy. This characteristic hinders the production of seedlings, due to the long period for germination and the unevenness of the seedlings. The specie Syagrus coronata , despite being widely used as food and economic resources, presents also seed dormancy, which hinders its propagation. Thus, this work aimed at evaluating the germination of S. coronata seeds using different methods of dormancy breaking and also, under different qualities of light and temperature. To do so, the seed endocarps were scarified by friction, puncture and complete removal of the endocarp, and the pre-soaking of seeds at different concentrations (50, 100, 200 and 400 mg L -1 ) of gibberellic acid (GA 3 ) and indolebutyric acid (IBA). We also evaluated the effect of germination in seeds exposed to different conditions of light (white, red, far red, blue and dark) and to different temperatures (25, 30, 35 and 20-30 °C). The data show that the act of rubbing the endocarp optimizes the seed germination process. Solutions containing growth regulators in the pre-soaking of seeds have a negative impact on germination. And the absence of light and the constant temperature of 25 °C are the most suitable for germination. The results indicate that S. coronata seeds have physical dormancy, and, despite obtaining greater germination in the dark, they are neutral photoblastic.

Morfofisiologia e anatomia foliar de mudas micropropagadas e aclimatizadas de abacaxizeiro cv. Smooth Cayenne em diferentes substratos

Morphophysiology and leaf anatomy of plantlets of pineapple cv. Smoth Cayenne acclimatized in different substrates This study aimed to determine the optimal substrate and ideal time for acclimatization in plants of the ‘Smooth Cayenne’ pineapple and compare anatomically plantlets cultivated in vitro with acclimatized plants. Shoots were inoculated on MS with BAP (6.66 µM). After three subcultures, the buds were transferred to MS medium for 30 days. The media were solidified with 0.7% agar, and the pH adjusted to 5.8 before autoclaving (120oC for 20 minutes). Cultures were kept in a growth room (25±1oC, irradiance of 35 i mol m- 2 s- 1 and 16 hours photoperiod). The shoots obtained in vitro were transplanted into plastic pots in a greenhouse, containing the following substrates: T1- Plantmax® + humus (P + H), T2-Plantmax ® + vermiculite (P + V) and T3-Plantmax ® (P). Anatomical cuts were made on leaves of plants maintained in vitro and plants with 20, 40 and 60 days of acclimatization on different substrates. The use of Plantmax® + humus substrate provided greater development in the acclimatization of plants. From 40 days of acclimatization, the plants showed anatomical features that may facilitate the adaptation to field conditions.