ABSTRACT Among the methods used for the restoration of altered areas, the planting of native tree seedlings is one of the most traditional ones. The objective of this study was to evaluate the survival and initial growth of Casearia sylvestris Sw, Handroanthus heptaphyllus Vell. Mattos and Parapiptadenia rigida Benth. Brenan seedlings in altered areas, according to containers used in nursery seedlings production and use of mulching on planting, using morphological and physiological attributes. The experiment was conducted in a 2x2 factorial scheme. The type of containers used (plastic bag and tube) was considered, and the presence or absence of mulching around the seedlings. The three species presented similar survival averages at 24 months. The rates between the treatments were 72.5; 85.0 and 80.0%, respectively. The use of plastic bags had a positive impact on the height (IncH) and stem collar (IncDC), crown area (CA) and shoot dry mass (SDM) for C. sylvestris and H. heptaphyllus, while for P. rigida, the use of plastic bags favored the CA and the SDM. The presence of mulching favored the attributes IncH, IncDC, AC, and MSPA of H. heptaphyllus, as well as CA and SDM of C. sylvestris. Regarding the physiological parameters (relative levels of chlorophyll a and b and fluorescence of chlorophyll a), no difference was observed between the treatments tested. It is recommended that for the planting of seedlings of C. sylvestris, H. heptaphyllus, and P. rigida, in altered areas by anthropization, they be produced in a 1.5 L plastic bag, aiming at greater field growth. Also, in the planting of C. sylvestris and H. heptaphyllus the mulching should be used to favor their growth.
RESUMO Entre os métodos utilizados para a restauração de áreas alteradas, tem-se o plantio de mudas arbóreas nativas como um dos mais tradicionais. O objetivo desse estudo foi verificar a sobrevivência e o crescimento de mudas de Casearia sylvestris Sw, Handroanthus heptaphyllus Vell. Mattos e Parapiptadenia rigida Benth. Brenan, em área alterada, de acordo com o recipiente utilizado na produção das mudas em viveiro e do uso de mulching no plantio, por meio de atributos morfológicos e fisiológicos. O experimento foi conduzido em esquema fatorial 2x2, considerando tipos de recipientes na produção das mudas (saco plástico e tubete) e presença ou ausência de mulching no entorno das mudas no plantio. As três espécies apresentaram médias de sobrevivência semelhantes aos 24 meses. As taxas entre os tratamentos foram 72,5; 85,0 e 80,0%, respectivamente. Obteve-se efeito positivo do uso de saco plástico para incremento em altura (IncH) e em diâmetro coleto (IncDC), área da copa (AC) e massa seca da parte aérea (MSPA) para C. sylvestris e H. heptaphyllus, enquanto para P. rigida, o uso do saco plástico favoreceu à AC e MSPA. A presença de mulching favoreceu os atributos IncH, IncDC, AC e MSPA de H. heptaphyllus, bem como a AC e a MSPA de C. sylvestris. Quanto aos parâmetros fisiológicos (níveis relativos de clorofila a e b e fluorescência de clorofila a), não foi observada diferença entre os tratamentos testados. Indica-se que mudas de C. sylvestris, H. heptaphyllus e P. rigida, para plantio em área antropizada, sejam produzidas em recipiente saco plástico de 1,5 L visando maior crescimento a campo. Além disso, no plantio de C. sylvestris e H. heptaphyllus deve-se utilizar o mulching para favorecer seu crescimento.
SUMMARY: Light is an important environmental factor in the establishment of vegetation. The knowledge of the behavior of the species in response to light demand for survival and growth in the field becomes essential. Thus, the present study aimed at evaluating the survival and initial growth of Myrocarpus frondosus seedlings under different levels of shade in the field. The treatments used were: 0 % (full sun); 18 %; 50 % and 70 % shading in a randomized block design. The survival of seedlings was evaluated 30 and 540 days after planting (d.a.p.) and the morphological attributes height (H), stem diameter (DC) and H/DC ratio every 90 days. Leaf area, leaf dry matter, dry matter of stem and branches and dry matter of shoot were obtained 540 d.a.p. The analyses of the physiological attributes fluorescence of chlorophyll a and photosynthetic pigments were performed 180, 360 and 540 d.a.p. The use of shading in the planting of Myrocarpus frondosus influences the survival and the morphological and physiological attributes of the species. The morphological and physiological attributes of Myrocarpus frondosus plants show that the species requires shading of 50 to 70 % in its initial growth phase in the field (540 d.a.p.). It is recommended to use the species in sub-forest enrichment plantations and in consortium with other species more demanding in light.
RESUMEN: La luminosidad es un factor ambiental importante en el establecimiento de la vegetación, siendo imprescindible el conocimiento del comportamiento de las especies en respuesta a la demanda de luz para supervivencia y crecimiento en el campo. El presente estudio tuvo como objetivo evaluar la supervivencia y el crecimiento inicial de plantas de Myrocarpus frondosus bajo diferentes niveles de sombreamiento en el campo. Los tratamientos utilizados fueron 0 % (pleno sol), 18 %, 50 % y 70 % de sombreamiento en un diseño de bloques al azar. La supervivencia de las plantas fue evaluada a los 30 y 540 días después de la plantación (ddp) y los atributos morfológicos altura (H), diámetro del cuello (DAC) y relación H/DC cada 90 días. A los 540 ddp se obtuvo el área foliar, materia seca foliar, materia seca del tallo y ramas y la materia seca de la parte aérea. Los análisis de los atributos fisiológicos fluorescencia de la clorofila α y los pigmentos fotosintéticos fueron realizados a los 180, 360 y 540 ddp. La utilización de sombreamiento en la plantación de Myrocarpus frondosus evidencian que la especie necesita de 50 y 70 % de sombra en la fase inicial de crecimiento en el campo (540 ddp). Se recomienda el uso de la especie en plantaciones de enriquecimiento de sub bosque y en consorcio con otras especies más exigentes en luminosidad.
Abstract In forest nurseries, one of the factors that change the growth and quality of seedlings is water supply, which has a direct influence on metabolic processes such as stomatal conductance and photochemical efficiency of photosystem II. This study aims to identify the influence of different watering regimes as well as the use of a water-retaining polymer on the initial growth and metabolic processes of Enterolobium contortisiliquum seedlings. The experimental design was in random blocks with a factorial scheme. Morphological attributes, as well as physiological and biochemical attributes were investigated. We verified that the performance of E. contortisiliquum seedlings depends on the watering regime provided to the plants; furthermore, up to 60 days after the application of the treatments, both the height and diameter of the collection and the leaf water potential were similar in the water regimes of 8 mm day-1 and 12 mm day-1.
ABSTRACT The use of a forest seedling bank has been recommended as an alternative to increase species richness in forest nurseries, as well as to produce seedlings of species that are diffi cult to propagate, especially those that belong to the late secondary and climax successional groups, which are not as commercially available. However, little is known about the impact of this method on forest dynamics. Thus, the present study aimed to examine the resilience and dynamics of a seedling bank in a remnant of a subtropical seasonal forest belonging to the Atlantic Forest Biome when subjected to different intensities of seedling removal. The experiment was conducted in a random block design in a factorial scheme (5 × 4), with treatments composed of fi ve intensities of removal of individuals from the seedling bank and the four seasons. The treatments were distributed into 18 blocks and the experimental units were composed of 1 m × 2.5 m plots. The resilience of the seedling community was assessed by examining effects of the fi ve removal intensities. The dynamics between the evaluation periods within each treatment were verifi ed by comparing the number of species and seedlings present before the treatments with those in the other evaluation periods. After one year, we found that tree-shrub vegetation had a partial capacity for restoration after withdrawal of individuals from the seedling bank. Our results show that the impact on the regeneration community can absorb the effects of up to 25% seedling removal. The technique of seedling transplantation may be recommended for species that have abundant regeneration, such as Actinostemon concolor, Eugenia rostrifolia, Trichilia claussenii and Nectandra megapotamica.