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In mixed-ploidy populations, newly formed polyploids initially occur at low frequencies when compared to diploids. However, polyploidy may lead to morphological and phenological changes, which promote reproductive isolation and favor polyploid establishment and reproductive success. Additionally, previous studies have shown that polyploidy can confer some adaptive advantages to organisms in stressful environments. Here, we investigate variation in reproductive phenology, floral traits and reproductive success between diploid and autotetraploid trees of Libidibia ferrea (Mart. Ex Tul.) L.P. Queiroz (Leguminosae) in a mixed tropical urban population, a stressful environment. We assessed ploidy levels, flowering and fruiting phenology, flowering synchrony, floral and reproductive biology, pollination and fruit and seed set. We tested the hypothesis that autotetraploid individuals have a higher frequency of pollinators and higher fruit and seed set per inflorescence (as a proxy of reproductive success) than diploids in an urban green space. Libidibia ferrea is a good model to test our hypothesis because it is self-incompatible (i.e. relies on pollinators to set fruits). In the urban ecosystem studied, we found that diploids flowered for 6-7 months/year and autotetraploids for 3-5 months/year. Flowering synchrony was low between and within cytotypes and even though autotetraploids and diploids exhibited some overlap in flowering period, diploids flowered alone for 2-3 months. Autotetraploids had significantly more flowers per inflorescences, larger flowers and larger pollen grains (as expected for polyploids), but also a higher frequency of visits by legitimate pollinators including two exclusive ones, and higher fruit and seed set per inflorescence when compared to diploids, despite having a shorter flowering period. Our findings reveal some advantages for polyploids over their related diploids in a tropical urban green space. Also, our results highlight the need for more studies that seek to understand abiotic mechanisms affecting reproductive output of polyploids in urban ecosystems.

Purpose – To investigate how the stages of the organizational life cycle influence the probability of violation of financial covenants. Theoretical framework – Companies in different stages of the organizational life cycle present different incentives when assuming a position regarding profitability, investment, dividend distribution, the evolution of sales, indebtedness, strategic planning, information disclosure, and earnings quality, and these factors are directly related with the inclusion and violation of financial covenants in debt contracts. Methodology – We used 1,328 observations of 197 non-financial Brazilian companies listed on the B3 in the period from 2010 to 2018. The accounting data were collected from the Economatica database and the financial covenant information was obtained from analyzing more than 2,400 company footnotes. To analyze the results, we used logistic regressions with year-controlled data. Findings – The results highlight that companies in the maturity stage present a lower probability of violating some limit stipulated in the financial covenants in their debt contracts than companies in the other stages, that is, introduction, growth, turbulence, or decline. Practical & social implications of research – In regulatory terms, the results presented further reinforce the need to revise CPC 26 (R1), making it obligatory to disclose the limits of restrictive clauses in explanatory notes for corporations. Originality/value – These results extend the literature by presenting evidence that it is not only the turbulence and decline phases that cause operational risks that can culminate in an increased probability of violation of financial covenants, but also the initial introduction and growth phases of companies. Keywords – financial covenants; organizational life cycle stages; violation of covenants. Objetivo – Investigar como os estágios do ciclo de vida organizacional influenciam a probabilidade de violação dos covenants financeiros. Referencial teórico – Empresas em diferentes estágios do ciclo de vida organizacional têm diferentes incentivos para se posicionar em termos de lucratividade, investimento, distribuição de dividendos, crescimento de vendas, endividamento, planejamento estratégico, divulgação de informações e qualidade dos lucros, bem como aqueles fatores que estão diretamente relacionados à inclusão e violação de covenants financeiros nos contratos de dívida. Metodologia – Foram utilizadas 1.328 observações de 197 empresas brasileiras não financeiras listadas na B3 no período de 2010 a 2018. Os dados contábeis foram coletados do banco de dados Economatica e as informações sobre covenants financeiros foram obtidas por meio da análise de mais de 2.400 notas explicativas societárias. Regressões logísticas foram usadas para analisar os resultados com os dados organizados por ano. Resultados – Os resultados demonstram que as empresas maduras são menos propensas a violar um limite estipulado por um covenant financeiro em um contrato de dívida do que empresas em outros estágios, ou seja, os estágios de introdução, crescimento, turbulência ou declínio. Implicações práticas e sociais da pesquisa – Em termos regulatórios, os resultados apresentados reforçam a necessidade de revisão do CPC 26 (R1), tornando obrigatória a publicação dos limites de covenants nas notas explicativas societárias. Contribuições – Esses resultados complementam a literatura ao apresentar evidências de que não são apenas as fases de turbulência e declínio que apresentam riscos operacionais que podem culminar em aumento da probabilidade de violação de covenants financeiros, e que as fases inicial e de crescimento também apresentam riscos. Palavras-chave – Covenants financeiros, estágios do ciclo de vida organizacional, violação de covenants.

Urban ecosystems provide green landscapes that are important to global biodiversity conservation. In tropical urban ecosystems, exotic plants are widely used in landscaping and this can have several negative effects on the native plant and pollinator communities. Here, we aimed to investigate the origin (native or exotic to Brazil, and native or exotic to the phytogeographic dominium where the urban space is inserted), sexual and reproductive systems and fruiting of tree species occurring in 17 urban green spaces in the city of Recife, Pernambuco, located in the northeastern Brazilian Atlantic forest. A total of 114 tree species were registered in the urban green spaces, 78 out of them were observed for fruiting. Overall, 49.1 % of the species are native to Brazil and 50.9 % are exotic, while 86 % do not occur naturally in the northeastern Brazilian Atlantic forest. In terms of abundance of individuals, these values were 37 % native, 63 % exotic and 80.5 % not occurring in the northeastern Brazilian Atlantic forest. Most of the species, native or exotic, are hermaphrodite and self-incompatible (i.e. obligatory cross-pollinated). From the 78 species observed for fruiting, 77 set fruits, 43.7 % had sub-annual pattern; all exotic species (43 spp.) set fruits, even the 13 exotic species that are self-incompatible. Our results reveal that factors such as the high use of exotic species that successfully set fruits in tropical urban green spaces may indicate risks for plant-animal interactions (e.g. pollination; dispersion), threaten the reproductive success of native plant species, increase the risk of biological invasion, and consequently impair the maintenance of biodiversity. We suggest that decision makers pay attention and consider the impacts of using exotic plant species in the dynamic of tropical urban ecosystems.