, LUCIMÁRIO PEREIRA BASTOS 6 RESUMO -A rizogênese é considerada uma fase crítica na regeneração de plantas in vitro, pois determina a sobrevivência das mesmas durante a aclimatização. Dentre os fatores determinantes na indução e na formação de raízes in vitro, destacam-se o genótipo e as auxinas. O objetivo deste trabalho foi avaliar o efeito de diferentes concentrações do ácido 4-indol-3-butírico (AIB) no enraizamento in vitro de dois genótipos de jenipapeiro (Genipa americana L.) JRB59 e JRB69, bem como no processo de aclimatização das microplantas utilizando diferentes substratos. Para o enraizamento, brotos com aproximadamente 2,0 cm de comprimento, provenientes do cultivo em meio de cultura com 6-benzilaminopurina (BAP), nas concentrações de 2,22; 8,87; 17,74 e 26,76 μM mais a testemunha com ausência do BAP, foram introduzidos em meio de cultura MS, suplementados com 4,9; 9,8 e 14,7 μM de AIB mais a testemunha com ausência de AIB. Quanto ao processo de aclimatização, utilizaram-se como substratos areia lavada, Plantmax ® HT e Ecoterra ® . As variáveis analisadas foram: porcentagem de enraizamento, número de raízes adventícias, comprimento da maior raiz, porcentagem de sobrevivência e altura das plantas na fase de aclimatização. Os resultados mostraram que a auxina AIB, na concentração de 9,8 μM, foi mais eficiente para indução do enraizamento, com percentual acima de 70%, para o genótipo JRB69, e 43,3% para o genótipo JRB59. O substrato Ecoterra ® influenciou significativamente na qualidade do sistema radicial e qualidade da parte aérea. Termos para indexação: rizogênese, auxinas, cultivo in vitro. IN VITRO ROOTING AND ACCLIMATATION OF GENOTYPES OF JENIPAPEIRO (Genipa americana L.)ABSTRACT-The rhizogenesis is considered a critical stage, since it determines the plant survival during the acclimatization. Among the determinative factors in the induction and the formation of in vitro roots, is distinguished the genotype and the auxin. The objective of the work was to evaluate the effect of different concentrations of acid 4-indol-3-butírico (IBA) in the in vitro rooting in genotype of Genipa americana L; as well as the process of acclimatization of the plant using different substrate. For the in vitro rooting stage, shoots of 2.0 cm long, proceeding from the culture medium with 6-benzilaminopurina (BAP) in concentrations of 2,22; 8,87; 17,74 and 26,76 μM plus the witness with absence of the BAP, were inoculated in medium MS supplemented with IBA (4.9; 9.8 e 14.7 μM) plus the witness with IBA absence. To the acclimatization process it was used as supporting material washed sand, Plantmax® HT and Ecoterra®. The variables analyzed were: percentage of rooting, number of adventitious roots, and length of the largest root, percentage of survival and height of the plant in the acclimatization phase. The results showed that IBA at 9.8 μM induced greater rooting percentage. The substrate Ecoterra® influenced significantly in the quality of root system and quality of the aerial part.
Alcantarea nahoumii occurs exclusively in the state of Bahia, Brazil, and is classifi ed as vulnerable due to deforestation and frequent fi res in the region. Knowledge of fl oral and reproductive biology is fundamental to understanding ecological interactions, as well as the reproductive success of plant species. Th e objective of this study was to evaluate the fl oral and reproductive biology of A. nahoumii in an Atlantic Forest fragment with regard to phenology, pollen viability, stigma receptivity, pollination ecology and reproductive systems, all of which are important parameters for of the development of conservation strategies for the species. Anthesis is diurnal and heterogeneous, starting at 6:30 a.m. and lasting until 8:00 a.m. Highest germination percentages and greatest pollen tube lengths were obtained in BK culture medium. Histochemical tests revealed high pollen viability (89.71 %). Stigma receptivity occurred during anthesis and lasted for up to 24 hours after fl oral opening. Alcantarea nahoumii exhibited preferential allogamy and self-compatibility, and required a pollinator to production of viable seeds. Sixteen species of pollinators were observed visiting A. nahoumii, among which were fi ve hummingbird species. Even though its reproductive system is effi cient, this bromeliad remains threatened mainly due to habitat fragmentation caused by deforestation, burning and predatory extractivism.
The objective of this study was to characterize the spatial distribution pattern at different altitude gradients as well as to investigate the flora associated with A. nahoumii, considered to be endemic and vulnerable. The study was carried out in Serra da Jibóia, Santa Teresinha, Bahia, Brazil. An inventory was conducted of young and adult A. nahoumii specimens along with taxonomic identification and quantification of the associated species. The cover percentage of A. nahoumii, rock slope, organic matter percentage and exposed rock percentage were calculated, as well as the following phytosociological parameters: absolute density, relative density, absolute frequency, relative frequency, and dominance of A. nahoumii. For the spatial distribution, three indices were tested (Morisita, McGuinnes and Payandech). Canonical correspondence analysis was also applied to test the association of the environmental variables with the species in the community. A total of 1,660 individuals were encountered and classified according to taxonomy in 17 families, 25 genera and 28 species. The spatial distribution pattern of the A. nahoumii population is aggregate. The results demonstrate that the population structure of A. nahoumii is stable, but events such as fires and extractive exploitation make the species vulnerable, along with the other species that inhabit the area. Key words: Bromeliaceae, conservation, endemism, dispersion index, floristic survey, plant diversity. ResumoO objetivo deste trabalho foi caracterizar o padrão de distribuição espacial da A. nahoumii em diferentes gradientes de altitudes, bem como realizar o levantamento florístico da vegetação associada a A. nahoumii, considerada endêmica e "Vulnerável". O estudo foi realizado na Serra da Jibóia, Santa Teresinha, Bahia, Brasil. Foi realizado um inventário de plantas jovens e adultas da A. nahoumii, bem como a identificação taxonômica e quantificação das espécies associadas, percentagem de cobertura da vegetação, percentagem de cobertura da A. nahoumii, inclinação da rocha, percentagens de matéria orgânica e rocha exposta. Foram calculados os parâmetros fitossociológicos: densidade absoluta, densidade relativa, frequência absoluta, frequência relativa e dominância da A. nahoumii. Para a distribuição espacial foram testados três índices: Índice de Morisita, McGuinnes e Payandech. Também foi realizada uma Análise de Correspondência Canônica para as variáveis ambientais com as espécies da comunidade. Um total de 1.660 indivíduos foram encontrados e classificados taxonomicamente em 17 famílias, 25 gêneros e 28 espécies. O padrão de distribuição espacial da população de A. nahoumii é agregado. Os resultados demonstram que a estrutura populacional da A. nahoumii está estável, mas eventos como queimadas e exploração extrativista, as tornam vulnerável, juntamente com as demais espécies que habitam a área. Palavras-chave: Bromeliaceae, conservação, endemismo, índice de dispersão, inventário florístico, diversidade de plantas.Spatial distribution and associated f...
ABSTRACT-The jaboticaba tree (Plinia sp.) is a native fruit tree belonging to the Myrtaceae family, which occurs spontaneously throughout Brazil. The estimation of genetic divergence among genotypes of native populations can be useful for conservation and knowledge of available genetic resources, in the formation of gene banks and breeding species. In order to evaluate the genetic diversity of jaboticaba trees identified in the Bahia Reconcavo municipalities, 35 genotypes were characterized by ISSR primers (Inter Simple Sequence Repeats). The 18 primers generated a total of 463 amplicons, and the number of initiator fragments ranged from 14 to 36, with an average of 25.72% and 99.65% polymorphism. Polymorphic information content ranged from 0.13 to 0.33 with a mean of 0.22 and the marker resolution power from 4.34 to 15.77, with an average of 8.67. Multivariate analysis allowed the formation of five groups of genetic divergence, where the longest distance was 0.97 between JCA6 and JSF8 genotypes and the lower of JMT2 and JCA1 (0.11). From the use of ISSR markers it is possible to check the variability between genotypes on the evaluated jaboticaba trees. Index terms: genetic diversity, ISSR, Plinia sp. CARACTERIZAÇÃO MOLECULAR DE GENÓTIPOS DE
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