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PREMISE: Long-distance dispersal has been important in explaining the present distributions of many plant species. Despite being infrequent, such dispersal events have considerable evolutionary consequences, because bottlenecks during colonization can result in reduced genetic diversity. We examined the phylogeographic history of Lycium carolinianum, a widespread taxon that ranges from southeastern North America to several Pacific islands, with intraspecific diversity in sexual and mating systems. METHODS: We used Bayesian, likelihood, and coalescent approaches with nuclear and plastid sequence data and genome-wide single nucleotide polymorphisms to reconstruct the dispersal history of this species. We also compared patterns of genetic variation in mainland and island populations using single nucleotide polymorphisms and allelic diversity at the S-RNase mating system gene. RESULTS: Lycium carolinianum is monophyletic and dispersed once from the North American mainland, colonizing the Pacific islands ca. 40,100 years ago. This dispersal was accompanied by a loss of genetic diversity in SNPs and the S-RNase locus due to a colonization bottleneck and the loss of self-incompatibility. Additionally, we documented at least two independent transitions to gynodioecy: once following the colonization of the Hawaiian Islands and loss of self-incompatibility, and a second time associated with polyploidy in the Yucatán region of Mexico. CONCLUSIONS: Long-distance dispersal via fleshy, bird dispersed fruits best explains the unusually widespread distribution of L. carolinianum. The collapse of diversity at the S-RNase locus in island populations suggests that self-fertilization may have facilitated the subsequent colonization of Pacific islands following a single dispersal from mainland North America.

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The aim of this study was to evaluate the cytotoxic and genotoxic potential of goji berry fruit-based pharmaceutical powders obtained from three pharmaceutical laboratories. The product A was tested at concentrations of 0.012; 0.025 and 0.05 g mL-1, and B and C at concentrations 0.02; 0.04 and 0.08 g mL-1. It was also evaluated the tea of the dried goji berry fruit (non-additives) in the concentrations 0.035; 0.07 and 0.14 g mL-1 for comparison to the results obtained with powdered goji berry. Tea concentrations in the two exposure times did not cause inhibition of cell division nor cellular alterations to meristem tissues. For the industrialized goji products, all concentrations analyzed caused significant antiproliferative effect to the tissues evaluated at the shortest time of analysis. There were no significant cellular changes in tissues exposed to industrialized goji. Therefore, under the conditions of analysis, goji berry powder, at the three concentrations evaluated, was cytotoxic to root meristems.(AU)

Objetivou-se na presente pesquisa avaliar, em células meristemáticas de raízes de A. cepa, nos tempos de exposição 24 e 48 horas, o potencial citotóxico e genotóxico de produtos farmacêuticos do fruto goji berry em pó, provenientes de três laboratórios farmacêuticos. O produto A foi avaliado nas concentrações 0,012; 0,025 e 0,05 g mL-1, e B e C nas concentrações 0,02; 0,04 e 0,08 g mL-1. Avaliou-se também o chá do fruto seco de goji (não aditivado), nas concentrações 0,035; 0,07 e 0,14 g mL-1, para comparação com os resultados obtidos do fruto em pó. Verificou-se que o chá nas concentrações avaliadas, nos dois tempos de exposição estabelecidos, não ocasionaram inibição da divisão celular e nem alterações celulares aos meristemas de raízes. Para os goji industrializados, todas as concentrações analisadas causaram efeito antiproliferativo significativo aos tecidos avaliados logo no menor tempo de análise considerado. Nenhum dos produtos industrializados causou número significativo de alterações aos meristemas analisados. Assim, os goji em pó foram citotóxicos ao bioensaio utilizado por terem acarretado relevante instabilidade genética aos meristemas de raízes.(AU)

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The aim of this study was to evaluate the cytotoxic and genotoxic potential of goji berry fruit-based pharmaceutical powders obtained from three pharmaceutical laboratories. The product A was tested at concentrations of 0.012; 0.025 and 0.05 g mL-1, and B and C at concentrations 0.02; 0.04 and 0.08 g mL-1. It was also evaluated the tea of the dried goji berry fruit (non-additives) in the concentrations 0.035; 0.07 and 0.14 g mL-1 for comparison to the results obtained with powdered goji berry. Tea concentrations in the two exposure times did not cause inhibition of cell division nor cellular alterations to meristem tissues. For the industrialized goji products, all concentrations analyzed caused significant antiproliferative effect to the tissues evaluated at the shortest time of analysis. There were no significant cellular changes in tissues exposed to industrialized goji. Therefore, under the conditions of analysis, goji berry powder, at the three concentrations evaluated, was cytotoxic to root meristems.

Objetivou-se na presente pesquisa avaliar, em células meristemáticas de raízes de A. cepa, nos tempos de exposição 24 e 48 horas, o potencial citotóxico e genotóxico de produtos farmacêuticos do fruto goji berry em pó, provenientes de três laboratórios farmacêuticos. O produto A foi avaliado nas concentrações 0,012; 0,025 e 0,05 g mL-1, e B e C nas concentrações 0,02; 0,04 e 0,08 g mL-1. Avaliou-se também o chá do fruto seco de goji (não aditivado), nas concentrações 0,035; 0,07 e 0,14 g mL-1, para comparação com os resultados obtidos do fruto em pó. Verificou-se que o chá nas concentrações avaliadas, nos dois tempos de exposição estabelecidos, não ocasionaram inibição da divisão celular e nem alterações celulares aos meristemas de raízes. Para os goji industrializados, todas as concentrações analisadas causaram efeito antiproliferativo significativo aos tecidos avaliados logo no menor tempo de análise considerado. Nenhum dos produtos industrializados causou número significativo de alterações aos meristemas analisados. Assim, os goji em pó foram citotóxicos ao bioensaio utilizado por terem acarretado relevante instabilidade genética aos meristemas de raízes.

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BACKGROUND AND AIMS: Polyploidy has important effects on reproductive systems in plants and has been implicated in the evolution of dimorphic sexual systems. In particular, higher ploidy is associated with gender dimorphism across Lycium species (Solanaceae) and across populations within the species Lycium californicum. Previous research on the association of cytotype and sexual system within L. californicum sampled a limited portion of the species range, and did not investigate evolutionary transitions between sexual systems. Lycium californicum occurs in arid regions on offshore islands and mainland regions in the south-western United States and Mexico, motivating a more comprehensive analysis of intraspecific variation in sexual system and cytotype across the full range of this species. METHODS: Sexual system (dimorphic vs. cosexual) was determined for 34 populations across the geographical range of L. californicum using field observations of pollen production, and was confirmed using morphological measurements and among-plant correlations of primary sexual traits. Ploidy was inferred using flow cytometry in 28 populations. DNA sequence data from four plastid and two nuclear regions were used to reconstruct relationships among populations and to map transitions in sexual system and ploidy. KEY RESULTS: Lycium californicum is monophyletic, ancestrally diploid and cosexual, and the association of gender dimorphism and polyploidy appears to have two evolutionary origins in this species. Compared with cosexual populations, dimorphic populations had bimodal anther size distributions, negative correlations between male and female floral traits, and larger coefficients of variation for primary sexual traits. Flow cytometry confirmed tetraploidy in dimorphic populations, whereas cosexual populations were diploid. CONCLUSIONS: Tetraploidy and gender dimorphism are perfectly correlated in L. californicum, and the distribution of tetraploid-dimorphic populations is restricted to populations in Arizona and the Baja California peninsula. The analysis suggests that tetraploidy and dimorphism likely established in Baja California and may have evolved multiple times.

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UNLABELLED: • PREMISE OF THE STUDY: An association between polyploidy and gender dimorphism has been noted in several plant lineages. Whereas the majority of Lycium species are diploid and have hermaphroditic flowers in cosexual populations, gender dimorphism (gynodioecy, dioecy) has been shown to be uniformly associated with polyploidy in previous studies. Preliminary field observations suggested that some populations of Lycium carolinianum were dimorphic, providing a test of this association.• METHODS: We assessed sexual systems and cytotype variation (to infer ploidy) across 17 populations of L. carolinianum. Comparison of flowers in cosexual and dimorphic populations were used to infer changes in reproductive morphology associated with the evolution of gynodioecy.• KEY RESULTS: The majority of populations were cosexual in gender expression, but dimorphism was present in the Yucatán and in some populations in Hawaii. Populations varied in ploidy and were either diploid or tetraploid. Floral sexual dimorphism was present in all gynodioecious populations, though the magnitude differed and was cryptic in some cases. Our results are consistent with the hypothesis that following the evolution of gynodioecy, flowers on hermaphrodites increased in size.• CONCLUSIONS: Dimorphic sexual systems have likely evolved convergently in L. carolinianum. In contrast to previous studies, dimorphism is not perfectly associated with polyploidy. Although our sample from the Yucatán was both tetraploid and dimorphic, all populations in Hawaii were diploid regardless of sexual system. Ongoing phylogeographic and mating system studies will contribute to our understanding of reproductive evolution in this widespread, polymorphic species.

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In North American Lycium (Solanaceae), the evolution of gender dimorphism has been proposed as a means of restoring outcrossing after polyploidization causes the loss of self-incompatibility. Previous studies of this process in Lycium focused on comparisons between species that differ in ploidy. We examined intraspecific variation in floral morphology and DNA content in populations of L. californicum to determine correlations between sexual system and cytotype. We also used nuclear ITS and GBSSI sequence data to determine whether diploid and polyploid forms represent the same phylogenetic species, and the phylogeographic relationships among populations and ploidy levels. Within populations, no variation in ploidy was found, although among populations there was a perfect correspondence between sexual system and cytotype. Diploid populations were all hermaphroditic, whereas tetraploid populations were all gender dimorphic. There was no clear geographic pattern to the occurrence of diploid and tetraploid forms. Phylogenetic analysis confirms that L. californicum, regardless of ploidy, forms a monophyletic group within the genus Lycium. Sequences from diploid and polyploid individuals did not form reciprocally monophyletic clades, indicating either multiple gains of polyploidy, ongoing gene flow between cytotypes, or lack of lineage sorting since the evolution of polyploidy. The correspondence between ploidy and sex expression is consistent with the hypothesis that polyploidization triggers the evolution of gender dimorphism in this and other Lycium species.

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Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber. Rooting percentage did not differ between origins, but higher values were encountered for medium without hormones. Subcultures increased significantly rooting percentage and reduced time to rooting. The leaves from micropropagated plants were thinner, did not exhibit hairs, and had poorly developed palisade parenchyma and less epicuticular waxes. In vitro leaves had lower stomatal density and their stomata were less functional when compared to acclimated leaves. A repopulation program of Lycium chilense based on microcutting culture, specialy using subcultures, is feasible. (AU)

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Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber. Rooting percentage did not differ between origins, but higher values were encountered for medium without hormones. Subcultures increased significantly rooting percentage and reduced time to rooting. The leaves from micropropagated plants were thinner, did not exhibit hairs, and had poorly developed palisade parenchyma and less epicuticular waxes. In vitro leaves had lower stomatal density and their stomata were less functional when compared to acclimated leaves. A repopulation program of Lycium chilense based on microcutting culture, specialy using subcultures, is feasible.

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Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber. Rooting percentage did not differ between origins, but higher values were encountered for medium without hormones. Subcultures increased significantly rooting percentage and reduced time to rooting. The leaves from micropropagated plants were thinner, did not exhibit hairs, and had poorly developed palisade parenchyma and less epicuticular waxes. In vitro leaves had lower stomatal density and their stomata were less functional when compared to acclimated leaves. A repopulation program of Lycium chilense based on microcutting culture, specially using subcultures, is feasible.

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