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Abstract. One of the main barriers to restoration is the arrival of diaspores in degraded areas. However, this process can be hampered in open areas without trees in the landscape. For that, artificial perches are used to attract and provide a landing area for avian seed dispersers, to enhance seed rain. Our objective was to evaluate the effect of the distance of artificial perches in relation to a forest fragment on the diversity and composition of seed rain in an agricultural fallow area, including alien invasive plant species. We also aimed to record and characterize the bird species that potentially act as seed dispersers. Thus, we used artificial perches at three different distances from a forest fragment (5, 25, and 50 m). Four seed traps were arranged under the perches at each distance, and four control seed traps were interspersed with these and distanced at 7.5 m. Furthermore, we placed four seed traps inside the forest fragment at 5 m from the edge. We also carried out 80 h of focal observation of the avifauna that used artificial perches. A total of 24 655 seeds were sampled across all treatments. There was a significant difference in seed abundance and richness between artificial perches, control seed traps, and forest seed traps. Seed deposition increased with distance from the forest fragment (50, 25, and 5 m). An ordination procedure indicated the formation of three plant seed communities, with the forest community being most distinct. The invasive exotic species Pittosporum undulatum (Australian cheesewood) was the third most abundant in the seed rain. We observed 24 bird species from 12 families using artificial perches. The Tyrannidae family was the most represented. We showed that artificial perches are efficient structures for attracting birds, increasing the richness and abundance of seed species. Artificial perches at 25 and 50 m were more efficient possibly due to the provision of greater visibility for birds. Therefore, artificial perches are efficient in increasing seed rain in the fallow area but should be used with caution in landscapes with the presence of alien species. These findings contribute to increasing knowledge about overcoming the first barrier to ecological restoration, which is the arrival of diaspores in degraded areas, and showing the importance of birds in this process.

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We describe 4 new records of Habenaria dutrae Schltr., a threatened orchid species that is endemic of Rio Grande do Sul state, Brazil. The new record, from Pontal da Barra, increases the distribution of H. dutrae by approximately 180 km south and represents the southernmost known location for the species. We also re-evaluate the conservation status of the species including the new records, finding it to be Endangered under criteria B2ab(iii); D.

The main goals of this study were to verify the existence of integumentary seed dormancy in Erythrina crista-galli seeds from mature pods and evaluate the seedling emergence from newly collected seeds in two stages of physiological maturation. Methods of overcoming dormancy were tested by comparing seedling emergence rate, mean emergence time and emergence index, with treatments: TC -control; T1-sanded and soaked in water for 48 h; T2 -sanded and soaked in water for 24 h; T3 -soaked in water without heating at the initial temperature of 60 °C, until reaching room temperature; T4 -only sanded; T5 -immature seeds. The results indicate that: i) newly collected seeds from mature pods do not require treatment to overcome dormancy; ii) immature seeds have germination similar to newly collected mature seeds.Keywords: cockspur coral tree, Fabaceae, physical dormancy RESUMO -Efeito do estágio de maturação e tratamentos pré-germinativos na emergência de Erythrina crista-galli L. Os objetivos deste trabalho foram verificar a existência de dormência tegumentar em sementes maduras de Erythrina crista-galli e avaliar a emergência de plântulas de sementes recém-coletadas, em dois estágios de maturação fisiológica. Foram testados métodos de superação de dormência, comparando-se taxa de emergência, tempo médio de emergência e índice médio de emergência das sementes, sendo os tratamentos: TC -controle; T1 -lixadas e embebidas em água por 48 h; T2 -lixadas e embebidas em água por 24 h; T3 -embebidas em água, fora do aquecimento, à temperatura inicial de 60 °C até atingir temperatura ambiente; T4 -apenas lixadas e T5 -sementes coletadas de legumes imaturos. Os resultados indicam: i) sementes recém-coletadas de vagens maduras não necessitam de tratamento para superação de dormência; ii) sementes imaturas apresentam germinação similar as maduras recém coletadas.Palavras-chave: corticeira-do-banhado, dormência física, Fabaceae