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The objective of this work was to carry out the in vitro establishment of Echynochloa polystachya aiming at obtaining a micropropagation protocol for works involving the selection of superior genotypes and the cultivation of the species. E. polystachya stems were collected in the municipality of Manaus-AM. Made available in DSpace on 2022-09-14T16:05:19Z (GMT). No. of bitstreams: 1 Articlee38075-ID60508.pdf: 747409 bytes, checksum: eab6003ac1f5d0b7529cb78eaca3f8e7 (MD5) Previous issue date: 2022

Banana is a crop with outstanding economic and social expression throughout the world, therefore, it is important to use appropriate methods of propagation. The micropropagation is an appropriate method because it is disease-free, unlike traditional methods that spread pests and diseases. The objective of this study was to evaluate the effect of silicon on foliar anatomy and chlorophyll content of banana plants culturedin vitro using temporary immersion bioreactor technology. Explants of ?Dwarf Cavendish? banana established in vitro were inoculated in bioreactors containing MS liquid medium. Treatments included silicon concentration (0 and 1 mLL-1) and frequency of immersions (every 4, 6, and 8 hours) lasting 1 minute per immersion. Cultures were maintained in a growth room at 27 ± 2 °C under LED light (50 μmol m-² s-¹) with a 16 h of photoperiod for 36 days. After that period, anatomical characteristics and chlorophyll content were evaluated. Higher values were observed for some characteristics validated in plants cultivated with silicon when compared to control. Silicon addition resulted in increased thickness of the leaf?s limb tissues, resulting in a larger mesophyll (563.122μm) which is the set of measurements of all leaf?s limb tissues, it also provided greater adaxial and abaxial stomatal density (0.108817μm and 0.305085μm) respectively, greater adaxial and abaxial polar diameter/equatorial diameter ratio (1.982 and 2.069) respectively, and increased chlorophyll a content (0.000134 mg·g-1 fresh weight) and a/b ratio (1.710425) of plants of banana ?Dwarf Cavendish? cultured in bioreactors. Made available in DSpace on 2022-02-10T18:00:55Z (GMT). No. of bitstreams: 1 AGRIS-Banana-Biorreactors-2021.pdf: 439742 bytes, checksum: 7be61f067486a2a989ef5869b39588b6 (MD5) Previous issue date: 2021

Myrciaria dubia (camu-camu) is an Amazon tree that produces a tart fruit with high vitamin C content. It is probably the fruit with the highest vitamin C content among all Brazilian fruit crops and it can be used to supplement daily vitamin C dose. This property has attracted the attention of consumers and, consequently, encouraged fruit farmers to produce it. In order to identify and select potential accessions for commercial exploitation and breeding programs, M. dubia has received considerable research attention. The identification and characterization of genetic diversity, as well as identification of the population structure of accessions preserved in germplasm banks are fundamental for the success of any breeding program. The objective of this study was to evaluate the genetic variability of 10 M. dubia populations obtained from the shores of Reis Lake, located in the municipality of Caracaraí, Roraima, Brazil. Fourteen polymorphic inter simple sequence repeat (ISSR) markers were used to study the population genetic diversity, which resulted in 108 identified alleles. Among the 14 primers, GCV, UBC810, and UBC827 produced the highest number of alleles. The study illustrated the suitability and efficiency of ISSR markers to study the genetic diversity of M. dubia accessions. We also revealed the existence of high genetic variability among both accessions and populations that can be exploited in future breeding programs and conservation activities of this species. Made available in DSpace on 2018-01-26T23:50:34Z (GMT). No. of bitstreams: 1 gmr1601gmr.16019409.pdf: 783649 bytes, checksum: d583e09256abc4dd7fc75d655ce38349 (MD5) Previous issue date: 2018-01-26

Made available in DSpace on 2019-12-13T00:43:53Z (GMT). No. of bitstreams: 1 ArtigoDiversityNutCBABv17p3823892017.pdf: 782391 bytes, checksum: d6af4a38d28c6ce3b14a6c5192ca18d3 (MD5) Previous issue date: 2017

Este trabalho teve como objetivo a avaliação das características anatômicas e fisiológicas de aguapé (Eichhornia crassipes) em resposta ao estresse por arsênio. As plantas de aguapé foram cultivadas em solução nutritiva hidropônica de Hoagland em casa de vegetação sob cinco concentrações de arsênio: 0,0; 0,25; 0,5; 1,0; e 2,0 mg L-1 por período de 20 dias. As plantas demonstraram aumento na taxa fotossintética, na condutância estomática, na transpiração e na relação Ci/Ca, bem como na atividade de todas as enzimas do sistema antioxidante, com maior atividade nas folhas em relação às raízes nos tratamentos contendo arsênio. As características anatômicas das folhas das plantas sob as maiores concentrações de arsênio mostraram aumento na densidade estomática, no índice estomático e na espessura do parênquima esponjoso. A anatomia radicular não evidenciou alterações decorrentes da intoxicação por arsênio e modificações nas características do xilema e floema, porém não houve prejuízos à sua estrutura e função. Dessa forma, o estresse por intoxicação pelo arsênio, nas concentrações testadas, não é evidente nas plantas de E. crassipes, e os mecanismos de tolerância são relacionados com modificações na anatomia e fisiologia das plantas. This work aimed to evaluate the anatomical and physiological characteristics of Eichhornia crassipes in response to arsenic stress. Plants of E. crassipes were grown in Hoagland hydroponic nutritive solution under greenhouse conditions at five arsenic levels: 0.0, 0.25, 0.50, 1.0 and 2.0 mg L-1 during 20 days. The plants showed an increase in photosynthetic rate, stomatal conductance, transpiration and Ci/Ca rate, as well as in the activity of all the enzymes in the antioxidant system, with higher activity in the leaves than in the roots, in all the treatments with arsenic. The anatomical characteristics observed on the leaves of the plants under higher arsenic levels showed an increase in stomatal density, stomatal index and spongy parenchyma thickness. Root anatomy showed no toxic evidences at any arsenic level; changes in the xylem and phloem characteristics were exhibited by the roots in the arsenic treatments, but no damage was caused to its structure and function. Thus, stress caused by arsenic intoxication at the levels tested, is not evident on E. crassipes plants, and the mechanisms of tolerance of E. crassipes are associated to anatomical and physiological changes.

Three experiments were carried out with the objective of achieving high effectiveness in calli induction from high heterozygosis leaf explants of Coffea arabica through indirect somatic embryogenesis. A randomized-block design in a 2x5 factorial arrangement made up of two media [BOXTEL & BERTHOULY (1996) and TEIXEIRA et al. (2004)] and five C. arabica genotypes were used in the first experiment. In the second experiment the embryogenic calli production potential was evaluated in ten genotypes. Each of them was considered as a treatment. In the third experiment the variations in both 2.4-D (2.5 e 20μM) and 2-iP (2.5 e 20μM) concentrations in TEIXEIRA et al. (2004) medium and secondary media were evaluated. Crops were kept in a growth room under darkness, at 25±2oC. The medium described by TEIXEIRA et al (2004) was found to be superior when compared to that described by BOXTEL & BERTHOULY (1996) in the 2.2 and 7.2 genotypes. An opposite behavior was noticed in 4.2 genotype, that is, BOXTEL & BERTHOULY (1996) had medium superiority. Both 3.0 and 5.0 genotypes had the same behavior in both media studied, which shows that the somatic embryo production depends on the genotype. Calli induction depends on the 2-iP and 2.4 D ratio. The 20.0μM of 2.4-D and 20.0μM of 2-iP combination caused the highest embryogenic calli induction rate.

Made available in DSpace on 2022-09-23T15:05:20Z (GMT). No. of bitstreams: 1 document.pdf: 131622 bytes, checksum: e2538f2b30fb9e5b92f1f2cca2cfa097 (MD5) Previous issue date: 2008

O alumínio é o metal mais abundante e o terceiro elemento mais comum na crosta terrestre, compreendendo aproximadamente 7% da sua massa total, e em solos ácidos, sua toxidez é o fator limitante de maior importância para a produtividade das culturas no mundo. Neste sentido, este trabalho busca determinar um método de avaliação do comportamento de porta-enxertos de videira, Paulsen 1103 e Gravesac, em condições estressantes de alumínio in vitro. As plantas matrizes foram mantidas em casa de vegetação, em condições controladas contra patógenos, e submetidas a fertirrigação com solução nutritiva para videira. Para seleção dos explantes, desinfestação, introdução e manutenção in vitro foram utilizadas metodologias de cultura de tecidos para a videira. Após a desinfestação, os explantes foram inoculados em tubos de ensaio contendo 15 mL de meio de cultura DSD1. As culturas in vitro foram transferidas para salas de crescimento e mantidas sob condições de temperatura de 25°C, fotoperíodo de 16 horas e intensidade luminosa de 40-45 μmol.m-2.s-1. A sustentação dos explantes no meio líquido foi obtida por intermédio de discos de cortiça previamente preparados e esterilizados. Os experimentos foram conduzidos com pH da solução igual a 4,0 e concentrações de Al, adicionadas na forma de AlCl3, variando de 0 a 1,375 mM. Após a autoclavagem do meio de cultivo, as doses de alumínio foram adicionadas ao meio de cultura em câmara de fluxo laminar e os valores de pH corrigidos para 4,0. Foram implantados dois experimentos. No primeiro, os explantes das duas variedades de porta-enxertos foram colocados diretamente no meio de cultura DSD1 líquido com diferentes concentrações de Al, onde ficaram por um período de 60 dias até a avaliação. No segundo experimento, os explantes foram introduzidos em mesmo meio, na ausência de alumínio. Após 30 dias em crescimento, as plantas in vitro foram selecionadas por tamanho e submetidas aos diversos tratamentos até a avaliação. O método para a avaliação dos efeitos fitotóxicos do alumínio sobre a cultura da videira em condições in vitro foi elaborado com base em estudos que tratam da toxidez por alumínio em solução nutritiva e da seleção de videiras in vitro. Avaliaram-se os efeitos dos tratamentos sobre o sistema radicular (número de raízes e massa seca), matéria fresca e seca total e matéria seca das folhas. O delineamento experimental utilizado foi inteiramente casualizado composto por seis vidros, contendo três plantas cada um, num total de sete tratamentos. Os porta-enxertos de videira Gravesac e Paulsen 1103, apresentam mecanismos de exclusão do alumínio via elevação do pH do meio de cultura. A variedade Gravesac apresentou respostas de variação de pH mais rápidas que a variedade Paulsen 1103. Ocorreu variabilidade nas respostas de crescimento de plantas in vitro em condições estressantes de H+ e Al+3. O desenvolvimento in vitro do porta-enxerto Paulsen 1103 foi superior ao do Gravesac para número de folhas, comprimento das raízes, área foliar, peso seco total. The aluminum is the most abundant metal and the third more common element in the terrestrial crust, with approximately 7% of your total mass and in acid soils, your toxicity is the limiting factor of larger importance for the productivity of cultures in the world. In this sense, this work search to determine a method of evaluation of the behavior of rootstock grapevine ‘Paulsen 1103’ and ‘Gravesac’, in stress conditions of aluminum in vitro. The plants were maintained in a greenhouse, in controlled conditions against diseases, and submitted the irrigation with nutritious solution for grapevine. For selection of the explants, disinfestations, introduction and in vitro maintenance were used methodologies of tissue culture for the grapevine. After the disinfestations, the explants were inoculated in tubes containing 15 mL of culture medium DSD1. The cultures in vitro were transferred for growth rooms and maintained under temperature conditions of 25°C, photoperiod of 16 hours and luminous intensity of 40-45 mol.m-2.s-1. The sustentation of the explants in the liquid culture medium was previously obtained through cork disks prepared and sterilized. The experiments were maintained with pH of the solution same to 4.0 and concentrations of Al, added in the AlCl³ form, varying from 0 to 1.375 mM. After the sterilization of the culture medium, the concentrations of aluminum were added to the culture medium in a laminar camera and the pH values corrected for 4.0. Two experiments were implanted. In the first, the explants of the two varieties of grapevine rootstock were placed directly in the liquid culture medium DSD1 with different concentrations of Al, where were maintained per 60 days until the evaluation. In the second experiment, the explants were introduced in the same culture medium, in the absence of aluminum. After 30 days in growth, the plants in vitro were selected by size and submitted to the several treatments until the evaluation. The method for the evaluation of aluminum fitotoxicity effects on the grapevine culture in vitro was elaborated with base in studies about the toxicity for aluminum in nutrition solution and the selection in vitro of grapevine. The effects of the treatments were evaluated on the radicular system (number of roots and sec mass), fresh mass and sec mass of leaves. The experimental delineate used was randomized composed by six glasses, containing three plants each one, in a total of seven treatments. The rootstock grapevine ‘Gravesac’ and ‘Paulsen 1103’, present mechanisms of aluminum exclusion through elevation of pH in the culture medium. The cv. ‘Gravesac’ presented answers variation of faster pH than ‘Paulsen 1103’. Its happened variability in the answers growth of plants in vitro in stress conditions of H+ and Al+3. The development in vitro of rootstock grapevine Paulsen 1103 was superior to Gravesac for number of leaves, length of roots, foliar area and total dry weight.

O objetivo desse trabalho foi avaliar o efeito do tipo de recipiente e da aplicação de ácido indolbutírico (AIB) no enraizamento de estacas de pitaya do cerrado (saborosa). Made available in DSpace on 2011-04-09T20:50:02Z (GMT). No. of bitstreams: 1 OPB1634.pdf: 52585 bytes, checksum: 5ba08c1b2b1b6693b43ec13322cc711b (MD5) Previous issue date: 2008-02-25 Suplemento. Edição dos Resumos do XI Congresso Brasileiro de Fisiologia Vegetal, Gramado, set. 2007.

Nota científica.

Este trabalho objetivou comparar plantas diplóides (2n=2x=38) e tetraplóides induzidos (2n=4x=76) de Dendrobium nobile Lindl., mediante análises estomática e morfométrica das folhas. Para a análise estomática, foram coletadas folhas completamente expandidas do terceiro nó, que foram submetidas aos procedimentos usuais em microtécnica vegetal para microscopia de luz e eletrônica de varredura. Foram avaliados a freqüência estomática, a freqüência das outras células epidérmicas, o índice estomático, os diâmetros polar e equatorial dos estômatos e a relação entre o diâmetro polar e o diâmetro equatorial. Para a análise morfométrica das folhas utilizadas nas análises estomáticas, foram avaliados a altura e o diâmetro do pseudobulbo e a largura e o comprimento das folhas. D. nobile apresentou estômatos elípticos, com laterais gradualmente inclinadas, sendo o tamanho dos estômatos inversamente proporcional ao nível de ploidia. As plantas poliplóides apresentaram menor crescimento quando comparadas com as diplóides. Portanto, foi possível distinguir plantas de D. nobile diplóides das plantas tetraplóides utilizando as análises estomática e morfométrica.

A micropropagação da amoreira-preta pode gerar plantas livres de vírus e em curto espaço de tempo. Com o objetivo de aprimorar técnicas de micropropagação de amoreira-preta cultivar Brazos (Rubus idaeus L.), segmentos nodais, oriundos de plântulas preestabelecidas in vitro foram excisados e inoculados em meio WPM (0, 50, 100, 150 e 200%), suplementado com diferentes concentrações de BAP (0; 0,5; 1,0; 2,0 e 4,0 mg L-1). Após a inoculação, os explantes foram transferidos para sala de crescimento a 27±1ºC, irradiância de 35 mmol m 2 s 1 e fotoperíodo de 16 horas, onde permaneceram por 60 dias. O delineamento experimental utilizado foi inteiramente casualizado, utilizando-se de quatro repetições com quatro explantes cada. Maior número de brotos foi proporcionado com 1,0 mg L-1 de BAP associado a 100% de meio WPM e maior comprimento médio dos brotos após 60 dias foi verificado em 1,0 mg L-1 de BAP associado a 200% de meio WPM. Maior peso de matéria seca da parte aérea foi obtido em meio WPM 200% acrescido de 0,5 mg L-1 de BAP.

The aim of this work was to evaluate the effect of Ponkan mandarin (C. reticulata) x Pêra sweet orange (C. sinensis) immature fruits storage and sucrose concentrations on embryos in vitro culture. Fruits with 3 to 4 cm in diameter were harvested and placed inside black polyethylene bags with lateral openings and stored at 5±1ºC during 135 days. Every 15 days a sample was removed, its embryos were excised and individually inoculated in test tubes containing 15 mL of MS medium (MURASHIGE & SKOOG, 1962) with sucrose (0, 1.5, 3, 6, 12, 18 and 24 g L-1) and 0.3 mg L-1 GA3 and 1 g L-1 activated charcoal. Those treatments rested 48 hours in the dark and later in a growth room at 27 ± 1ºC with a 16-h photoperiod and 32 ?mol m-2 s-1 light intensity. Immature fruits can be stored for posterior excision and embryos culture. Fruits with 120 days after the pollination can be stored for at most 135 days without damaging the embryos viability. It was observed a better development of the aerial part and root system of plantlets from Ponkan mandarin x Pêra sweet orange embryos inMS medium with 12-18 g L-1 sucrose.

Com o objetivo de avaliar o período de vemalização sobre a incidência do índice de pseudoperfilhamento em plantas de alho (Allium sativum L.) cultivadas in vitro, visando maior multiplicação, foi conduzido este experimento em laboratório da UFLA (MG). Made available in DSpace on 2018-07-14T01:01:55Z (GMT). No. of bitstreams: 1 HorticulturaBrasileirav.22n.3p.5855882004.pdf: 3338688 bytes, checksum: 5cfb226baf7986057456a8d738e562b6 (MD5) Previous issue date: 2005-01-29

Com o objetivo de avaliar o tempo de vernalização para obtenção do pseudoperfilhamento de plantas de alho (Allium sativum L.) in vitro por meio da técnica de cultura de tecidos. Suplemento. Edição de Resumos expandidos e palestras do 43. Congresso Brasileiro de Olericultura, Recife, jul. 2003.

Com o objetivo de avaliar o tempo de vernalização para obtenção do pseudoperfilhamento de plantas de alho (Allium sativum L.) in vitro por meio da técnica de cultura de tecidos, foi conduzido experimento no Laboratório de Cultura de Tecidos da Universidade Federal de Lavras (MG). Made available in DSpace on 2015-11-11T04:12:36Z (GMT). No. of bitstreams: 1 27405.pdf: 31986 bytes, checksum: b81480ac41e62c90e82b966582dfe31a (MD5) Previous issue date: 2003-10-24 Suplemento. Edição de Resumos expandidos e palestras do 43. Congresso Brasileiro de Olericultura, Recife, jul. 2003.