Does Carbon-Based Material Influence Tropical Grasses Under Water Deficit?

Carbon-based materials (CM) have been investigated for their potential to improve plant responses to abiotic stresses, including water deficit, but their effects on tropical forage grasses remain poorly understood. The objective of this study was to assess whether CM affects the productivity of tropical grasses under water deficit. Two experiments were conducted, each with cultivars that are hybrids of Urochloa spp.: Sabiá grass and Cayana grass. The study was carried out in a greenhouse using four treatments arranged in a 2 × 2 factorial design. Treatments consisted of two water availability conditions (with and without water deficit) and two strategies (with and without application of CM). Evaluations were performed over two growth cycles. For Cayana grass, forage production was not affected by water deficit, and CM did not increase forage production. In contrast, water deficit impaired the development of Sabiá grass, and CM application increased forage mass regardless of water availability and maintained a lower phyllochron under water deficit. Carbon-based material increased forage production in Sabiá grass but not in Cayana grass, indicating that their effects may depend on the grass genotype and the conditions under which water deficit occurs.