Abstract Background and Aims: Environmental factors can interact with plant life history to determinate the reproductive strategies of adult plants and seedling recruitment. We expect that widely distributed tree species produce heavier seed and with greater variation in seed size than shrubs of restricted geographic distribution. We also predict that widely distributed tree species should be capable to germinate and develop under variable range of light conditions, while sun-adapted shrubs should germinate and develop better under high light intensity. We used as models two congeneric species of Fabaceae. Copaifera langsdorffii is a widely distributed arboreal species and C oblongifolia is a shrub with restricted distribution. Methods: Seeds were collected from two plant species in a Cerrado vegetation area, northern Minas Gerais, Brazil. The effects of light available on seed germination and seedling development was conducted in a germination chamber with controlled photoperiod, temperature and light intensity. Key results: The widely distributed tree (C. langsdorffii) had greater seed mass than the shrub (C. oblongifolia). Seeds of C. langsdorffii germinated faster under available high light, while the shrub C. oblongifolia seeds required less time to germinate under available low light and darkness. Under high light intensity, germination percentage of C. langsdorffii and C. oblongifolia seeds did not vary. However, seeds of the shrub showed a higher germination percentage under low light intensity and darkness. In general, seed mass showed a negative relationship with germination percentage, but this relationship varied in function of species and the availability of light. Copaifera langsdorffii seedlings had larger shoots and roots than C. oblongifolia. In contrast, the root:shoot ratio was higher in shrub than in tree species. Conclusions: Our results have important implications for understanding the patterns of distribution of two Copaifera species and explain the ability of C. oblongifolia to colonize disturbed areas.

Resumen Antecedentes y Objetivos: Los factores ambientales pueden interactuar con la historia de vida de las plantas determinando las estrategias reproductivas de individuos adultos y el reclutamiento de plántulas. Predecimos que las especies de árboles ampliamente distribuidas producen semillas más pesadas y con una mayor variación en el tamaño de las semillas que los arbustos de distribución geográfica restringida. Esperamos que las especies arbóreas ampliamente distribuidas deberían ser capaces de germinar y desarrollarse bajo un rango variable de condiciones de luz, mientras que los arbustos adaptados a condiciones de sol deberían germinar y desarrollarse mejor con una alta intensidad de luz. Usamos como modelo dos especies congenéricas de Fabaceae. Copaifera langsdorffii es una especie arbórea ampliamente distribuida y C. oblongifolia es un arbusto de distribución geográfica restringida. Métodos: Se colectaron semillas de estas especies de plantas en un área de vegetación de Cerrado, al norte del estado de Minas Gerais, Brasil. Los efectos de la disponibilidad de luz sobre la germinación de semillas y el desarrollo de plántulas se realizaron en una cámara de germinación con fotoperíodo controlado, temperatura e intensidad de luz. Resultados clave: El árbol de amplia distribución (C. langsdorffii) tuvo mayor masa de semillas que el arbusto (C. oblongifolia). Las semillas de C. langsdorffii germinaron más rápido bajo alta disponibilidad de luz, mientras que las semillas de C. oblongifolia requirieron menos tiempo para germinar bajo poca luz disponible y oscuridad. En alta intensidad de luz, las semillas de C. langsdorffii y de C. oblongifolia tuvieron similares porcentajes, mientras que las semillas de C. oblongifolia mostraron una mayor germinación en baja intensidad de luz y oscuridad. La masa de semillas mostró una relación negativa con el porcentaje de germinación, pero esta relación varió en función de las especies y de la disponibilidad de luz. Las plántulas de C. langsdorffii tuvieron mayor desarrollo de brotes y raíces que C. oblongifolia. En contraste, la relación raíz:brote fue mayor en arbustos que en árboles. Conclusiones: Nuestros resultados tienen implicaciones importantes para comprender los patrones de distribución de dos especies de Copaifera y poder explicar la capacidad de C. oblongifolia para colonizar áreas perturbadas.

Os insetos galhadores são herbívoros sedentários sofisticados que apresentam alto nível de especialização com sua planta hospedeira, mas sua performance pode ser afetada por fatores bióticos e abióticos. Neste estudo nós testamos duas hipóteses: a) plantas que possuem maior número de vizinhos coespecíficos apresentam maior riqueza e abundância de insetos galhadores, e b) a competição interespecífica é uma força capaz de molda a organização das comunidades de insetos herbívoros associados com uma planta super-hospedeira. O sistema Copaifera oblongifolia (Fabaceae)/ insetos galhadores associados foi usado para testar estas hipóteses. Os trabalhos de campo foram desenvolvidos em áreas de Cerrado do norte de Minas Gerais, Brasil. Para testar a primeira hipótese, nós avaliamos, com modelos lineares generalizados de efeitos mistos, os efeitos do número de vizinhos coespecíficos na riqueza e abundância de galhas associadas com 67 arbustos de C. oblongifolia pertencentes a duas populações. Para testar a segunda hipótese, nós usamos modelos nulos para avaliar se um arbusto de C. oblongifolia colonizado por uma espécie de inseto galhador é preferido ou evitado por uma outra espécie de inseto galhador. Um total de 2901 insetos galhadores pertencentes a 15 diferentes espécies foi coletado nos 67 arbustos de C. oblongifolia. Nós observamos uma relação negativa entre o número de vizinhos coespecíficos e a riqueza e a abundância de insetos galhadores associados com C. oblongifolia. Assim, nossos resultados não corroboraram a hipótese da concentração do recuro e nós usamos a teoria da diluição do recurso para explicar este resultado. Nossos resultados também mostraram que o padrão de co-ocorrência dos insetos galhadores na planta hospedeira não diferiu daquele esperado pelo acaso. Portanto, a estrutura da comunidade de insetos galhadores associada com C. oblongifolia não pode ser atribuída a eventos determinísticos com a competição interespecífica.

Gall-forming insects are sophisticated sedentary herbivores that present high level of specificity with host plant, but their performance can be affected by biotic and abiotic factors. In this study we have tested two predictions: a) plants that have a greater number of conspecific neighbors have greater richness and abundance of gall-forming insects, and b) interspecific competition is a force capable of shaping the organization of gall-forming insect communities in super-host plants. We used the Copaifera oblongifolia (Fabaceae)/galling insects' system to test these predictions. Fieldwork was carried out in areas of Cerrado (Brazilian Savanna) in northern Minas Gerais, Brazil. To test the first hypothesis, we evaluated with generalized linear mixed models, the effects of the number of conspecific neighbors on the richness and abundance of galls associated with 67 C. oblongifolia individual plants belonging to two populations. To test the second hypothesis, we used null models to evaluate whether a plant of C. oblongifolia colonized by a species of gall is preferred or avoided by another species of gall. A total of 2901 gall-forming insects belonging to 15 species were collected from the host plant C. oblongifolia. We observed negative relationships between the number of conspecific neighbors and the abundance and richness of gall-forming insects associated C. oblongifolia. Thus, our data did not support the resource concentration hypothesis. Instead, we used the resource dilution theory to explain the negative relation between resource concentration and frequency of attack by galling insects. Our results also showed that the co-occurrence pattern of gall-forming insects in the host plant did not differ from those expected by chance. Therefore, the structure of the gall-forming insect community associated to single C. oblongifolia plants cannot be attributed to deterministic factors such as interspecific competition.

ABSTRACT The timing of phenological events varies within and among populations, affecting the performance of individual plants differently. We evaluated the effects of relative variation in sprouting time on the display of reproductive events, vegetative growth and herbivory in Copaifera langsdorffii (Fabaceae). A total of 93 trees of C. langsdorffii was monitored daily to determine their sprouting time. We collected ten terminal branches of each plant to evaluate vegetative growth, production of defense compounds and insect herbivore damage. The sprouting time for the studied population lasted 67 days. Variation in sprouting time did not affect the probability of plants to enter the reproductive stage. Plants that entered the reproductive stage showed greater vegetative biomass. Variation in sprouting time had a negative relationship with branch growth and a positive relationship with the number of leaflets. Leaf phenol concentration did not vary in relation to sprouting time or plant phenology, but herbivory was higher in plants that sprouted later. The relationships among plant sprouting time, vegetative development and display of reproductive stage in C. langsdorffii are discussed. The results of this study also suggest that early sprouting prior to the rainy season is a strategy used by C. langsdorffii to escape herbivores attacks.