Intraspecific trait variability of a typical tree species of riverine forests in southern Brazil

Neste estudo foram caracterizados morfologicamente frutos, sementes e plântulas de espécies da Floresta com Araucária (Floresta Ombrófila Mista), visando entender as estratégias de estabelecimento de diferentes grupos ecológicos. Frutos de 18 espécies arbóreas foram coletados na região de Curitiba, Paraná. As sementes foram semeadas em vermiculita e mantidas em laboratório, até a fase de plântula. Nas espécies pioneiras predominam frutos secos, deiscentes, sementes exalbuminosas, pequenas, com estruturas que favorecem a dispersão anemocórica e plântulas com cotilédones finos, foliáceos com tricomas. Nas secundárias tardias os frutos são carnosos com dispersão zoocórica, as sementes são albuminosas e as plântulas possuem cotilédones crassos, foliáceos, e, em alguns casos, também com função de reserva. Nas secundárias iniciais, as características são variáveis. A caracterização morfológica realizada dá subsídio, no contexto da ecologia funcional, à interpretação das diferentes estratégias de estabelecimento das espécies.AbstractMorphology of diaspore and seedling of tree species of the Araucaria forest (Subtropical Ombrophilous Forest) in southern Brazil. This study characterized morphologically the fruits, seeds and seedlings of species of Araucaria Forest, aiming to understand the strategies of establishing different successional groups. Therefore, fruits of 18 tree species were collected in Curitiba, Paraná. Then the seeds were sown in vermiculite and remained in the laboratory until the seedling stage. The pioneer species have predominantly dehiscent dry fruits, unalbuminous seeds, small structures that favor anemochoric dispersal and seedlings with thin cotyledons, foliaceous with trichomes. In late secondary species the fruits are fleshy with zoochorous dispersal, seeds are albuminous and seedlings present fleshy cotyledons, foliaceous, and in some cases also reserve function. In the early secondary species, the characteristics are variable. Morphological characterization allows the interpretation of functional ecology, the different strategies of establishment of species.Keywords: Succession groups; establishment; functional morphology; Mixed Ombrophilous Forest.

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Diversity of parental environments increases phenotypic variation in Arabidopsis populations more than genetic diversity but similarly affects productivity

Annals of Botany ◽

10.1093/aob/mcaa100 ◽

2020 ◽

Cited By ~ 1

Author(s):

Javier Puy ◽

Carlos P Carmona ◽

Hana Dvořáková ◽

Vít Latzel ◽

Francesco de Bello

Keyword(s):

Genetic Diversity ◽

Environmental Conditions ◽

Phenotypic Variation ◽

Ecosystem Functioning ◽

Phenotypic Variability ◽

Population Type ◽

Diversity Effect ◽

Environmental Fluctuations ◽

Intraspecific Trait Variability ◽

Trait Variability

Abstract Background and Aims The observed positive diversity effect on ecosystem functioning has rarely been assessed in terms of intraspecific trait variability within populations. Intraspecific phenotypic variability could stem both from underlying genetic diversity and from plasticity in response to environmental cues. The latter might derive from modifications to a plant’s epigenome and potentially last multiple generations in response to previous environmental conditions. We experimentally disentangled the role of genetic diversity and diversity of parental environments on population productivity, resistance against environmental fluctuations and intraspecific phenotypic variation. Methods A glasshouse experiment was conducted in which different types of Arabidopsis thaliana populations were established: one population type with differing levels of genetic diversity and another type, genetically identical, but with varying diversity levels of the parental environments (parents grown in the same or different environments). The latter population type was further combined, or not, with experimental demethylation to reduce the potential epigenetic diversity produced by the diversity of parental environments. Furthermore, all populations were each grown under different environmental conditions (control, fertilization and waterlogging). Mortality, productivity and trait variability were measured in each population. Key Results Parental environments triggered phenotypic modifications in the offspring, which translated into more functionally diverse populations when offspring from parents grown under different conditions were brought together in mixtures. In general, neither the increase in genetic diversity nor the increase in diversity of parental environments had a remarkable effect on productivity or resistance to environmental fluctuations. However, when the epigenetic variation was reduced via demethylation, mixtures were less productive than monocultures (i.e. negative net diversity effect), caused by the reduction of phenotypic differences between different parental origins. Conclusions A diversity of environmental parental origins within a population could ameliorate the negative effect of competition between coexisting individuals by increasing intraspecific phenotypic variation. A diversity of parental environments could thus have comparable effects to genetic diversity. Disentangling the effect of genetic diversity and that of parental environments appears to be an important step in understanding the effect of intraspecific trait variability on coexistence and ecosystem functioning.

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