How Shading and Container Type Influence Ilex paraguariensis A.St.-Hil. Seedling Production

This study aimed to evaluate the influence of containers and shading on Ilex paraguariensis A.St.-Hil (yerba mate) seedling growth. We used a completely randomized design with a 3 x 2 factorial arrangement (containers x shading). We used PlantPaper (R), Ellepot (R) (both biodegradable containers composed of cellulose fibers), and polypropylene tube containers and shaded (75% shading screen) and unshaded (without shading screen) greenhouse environments. We measured height and stem diameter every 30 days and shoot and root dry biomass 210 days after sowing. With these data, we calculated the total dry biomass, Dickson quality index, and height/diameter ratio. The unshaded environment increased yerba mate seedlings growth in height and stem diameter. In unshaded environments, seedlings produced in biodegradable containers had greater growth than those produced in polypropylene tubes. In the shaded environment, however, seedlings produced in polypropylene tubes had better growth. Despite the differences observed between treatments, all seedlings presented adequate growth during the nursery phase. We suggest the use of biodegradable containers to produce yerba mate seedlings in unshaded environments. Study Implications: The production of quality Ilex paraguariensis A.St.-Hil (yerba mate) seedlings results in better mature plants in the field. The use of biodegradable containers reduces residues in the field and improves seedling root formation by eliminating root damage related to seedling extraction from containers. The result is more vigorous plants that perform better in the field. The implementation of better techniques for producing seedlings can help farmers reduce costs and improve the final quality of seedlings.