Preliminary Evaluation of Four Legume and Grass Species to Compose Roadside Revegetation in Piauí, Brazil

A trial was conducted to investigate the growth and production characteristics of four plant species, marking the initiation of research on roadside revegetation processes in the southern region of Piauí state, Brazil. The trial was conducted in greenhouse conditions to evaluate the response of the species—two native legumes (Arachis pintoi and Stylosanthes macrocephala) and two grasses (Brachiaria humidicula—non-native and Paspalum notatum—native)—under different fertilization and irrigation treatments. Data were collected in two harvest operations, measuring the following variables: total plant height, population density per pot, number of live leaves, plant moisture content, total forage biomass, and root biomass. The results suggested that fertilization and irrigation caused no significant effect on the major species development characteristics that allay with the highway agency interests. Arachis pintoi showed the best results with the lowest height (24.1 cm in Experiment 1 and 19.2 cm in Experiment 2) and the greatest total forage biomass yield (6.4 g plant−1 in Experiment 1 and 4.1 g plant−1 in Experiment 2). Thus, we recommend that the results found in this study should be extended to field experiments and long-term research. Because our study did not explore mixed-species designs, adopting such evaluation could offer advantages in achieving more comprehensive and resilient revegetation outcomes and help decision-making regarding target species to compose the roadside revegetation operations.