Biomass allocation in three species of <i>Leiothrix</i> (Eriocaulaceae) from phosphorus poor soils of the tropical grasslands of <i>Campos Rupestres</i>

BACKGROUND AND AIMS: Plants of resource-limited environments face unique challenges in dry mass allocation and nutrient acquisition strategies. In this study, we investigated how body size influences dry mass allocation patterns and the role of phosphorus (P) availability in shaping these strategies in Leiothrix (Eriocaulaceae) species native to the campos rupestres ecosystem. METHODS: We sampled three Leiothrix species across distinct P soil contents, and analyzed dry mass allocation to roots, rhizomes, and leaves. Generalized linear models and standardized major axis estimation were employed to assess allometric patterns and the influence of soil P on biomass allocation. KEY RESULTS: All species showed allometric scaling in dry mass allocation with increasing ramet size, although patterns differed among organs and species. Soil phosphorus availability mediated trade-offs among vegetative organs, with the strongest responses observed in Leiothrix mucronata. CONCLUSIONS: Dry mass allocation in Leiothrix species reflects the combined influence of plant size and soil phosphorus availability, which together shape allocation relationships among vegetative organs. Our findings provide insights into the ecological strategies of plants in resource-limited environments, with potential implications for conservation and management practices in campos rupestres ecosystems.