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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11847
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Item Distyly and variation in floral traits in natural populations of Psychotria ipecacuanha (Brot.) Stokes (Rubiaceae)(Brazilian Journal of Botany, 2005-04) Oliveira, Luiz Orlando de; Vieira, Milene F.; Rossi, Ana Aparecida B.Psychotria ipecacuanha is a perennial, medicinal herb that grows in clusters in the understory of humid, shady areas of the Atlantic Rain Forest of southeastern Brazil. The present study characterized the variation in floral traits among 35 clusters from three natural populations of this plant species. Field observations showed that the clusters are isomorphic, that is, a given cluster will either set long-styled or short-styled flowers. Stigmas and anthers are reciprocally placed in each morph, a dimorphism characteristic of distyly. The populations are isoplethic, that is, a given population exhibits an equilibrium 1:1 ratio of floral morphs. Morphometric analyses revealed that anther length, stigma length, corolla diameter, and pollen grain diameter were consistently greater in short-styled flowers, regardless of the population investigated. Significant differences for floral traits in the short-styled morph were found among populations. Floral traits in the long-styled morph also showed some significant differences among populations, but not for stigma height and corolla length. Controlled pollinations carried out in natural populations showed that fruit production was higher after inter-morph pollination. Nevertheless, observations of pollen tube growth in style, and also fruit production after spontaneous self-pollination and intra-morph pollination, indicated partial intramorph compatibility in this plant species.Item Reproductive studies in ipecac (Psychotria ipecacuanha (Brot.) stockes; Rubiaceae): pollen development and morphology(Brazilian Archives of Biology and Technology, 2008-09) Oliveira, Luiz Orlando de; Souza, Margarete Magalhães; Martins, Ernane Ronie; Pereira, Telma Nair SantanaThe aim of this work was to carry out the reproductive studies on Brazilian accessions of ipecac, Psychotria ipecacuanha. It presented heterostyly, with brevistylous and longistylous flowers. The pollen development was observed from the sections of the anthers embedded in resin. Anther development was normal as usually observed in dicotyledones, displaying four layers: outer epidermis, endothecium, middle layer and inner tapetum. The pollen was bicellular and filled with starch at the microspore stage. Pollen morphology was studied using SEM, which showed pollen polymorphism within and between the two floral morphs. Five types of pollen with reticulate or perforate exine were identified. The characteristics showed that the sexual process was as important as the vegetative propagation for the reproduction of this species.Item Teor e composição do óleo essencial de cinco acessos de mentrasto(Química Nova, 2004-01) Oliveira, Luiz Orlando de; Barbosa, Cláudio de Almeida; Ferreira, Francisco Affonso; Silva, Derly José Henriques da; Mosquim, Paulo Roberto; Nascimento, Evandro Afonso; Castro, Henrique Guilhon deThis study aimed to analyse the content and the composition of the essential oil of five accesses of mentrasto (Ageratum conyzoides). Five accesses of mentrasto with three repetitions were used. The accesses were obtained in Mariana-MG (AMA), Piranga-MG (API), Visconde do Rio Branco (ARB) and Viçosa-MG (AVB and AVP). The essential oil was obtained by hydrodistillation and the identification of the oil components by CG and GC/MS. The ARB access presented the higher essential oil content, that is 0.70% (P < 0.05). Eleven chemical compounds were identified. The precocene I was the main constituent in the access API, and the precocene II was the main constituent in the accesses AMA, ARB, AVB and AVP.Item Clonal diversity and conservation genetics of the medicinal plant Carapichea ipecacuanha (Rubiaceae)(Genetics and Molecular Biology, 2009-07-01) Oliveira, Luiz Orlando de; Venturini, Bruna Afonso; Rossi, Ana Aparecida Bandini; Hastenreiter, Saulo SantosThe roots of the understorey shrub Carapichea ipecacuanha (ipecac) have medicinal properties, and the uprooting of wild plants has supplied most of the world demand for this species. Although under severe population decline, C. ipecacuanha lacks legal protection. In the wild, the aerial stems of ipecac clump together to form clusters with well-defined borders. Cluster size may range from several to hundreds of aerial stems. To investigate the extent of clonality among aerial stems in ipecac clusters, we sampled 50 wild clusters (a total of 291 aerial stems) and screened them with 89 inter-simple sequence repeat (ISSR) markers. The 291 aerial stems were grouped into 42 putative clones. The clonal groups generally consisted of aerial stems from the same cluster, and there was little or no genetic differentiation among aerial stems at the cluster level. These findings suggest that strategies designed to conserve ipecac in situ should not rely upon census data, which are based on the number of aerial stems per cluster and the number of clusters per population, because such data greatly underestimate the species effective population size and genetic diversity. Our results also indicate that this species needs protection at a federal level.