Growth and quality of Brazilian pine tree seedlings as affected by container type and volume

Abstract

Araucaria angustifolia (Bert.) O. Kuntze (Araucariaceae), commonly known as araucaria and Brazilian pine tree, can be grown for their edible pine nuts (pinhões), medicinal properties, and ornamental purposes. The aim was to assess the shoot and root growth and the overall quality of A. angustifolia seedlings grown in containers with different sizes, shapes and composition. Seeds were sowed in five containers: I – 126cm³ polypropylene cone-tainers (small cone-tainers); II – 290cm³ cone-tainers (large cone-tainers); III – 879cm³ polyethylene black bags; IV- 275 cm³ nonwoven fabric (TNT) containers (small TNT container) and; 493 cm³ nonwoven fabric (TNT) containers (large TNT container). Seedlings were evaluated 210 days after sowing, regarding the following variables: aboveground height (cm), root collar diameter (mm), shoot dry mass (g), roots dry mass (g), total dry mass (g), leaf area (cm²), roots area (cm²), roots volume (cm³), sturdiness quotient, root-shoot ratio and Dickson quality index. Height was superior for seedlings grown in the plastic bags (27.6 cm) and the large TNT containers (27.02 cm) when compared to the small and large cone-tainers (21.75 and 21.78 cm, respectively). Plastic bags also presented greater values of root-collar diameter, shoots, roots and total biomass and Dickson Quality index. Small and large TNT containers promoted lower root area and volume when compared to large polyethylene cone-tainers, but allowed for the same or better aboveground growth. Taking all results analyzed together, the polyethylene black bag promoted better growth and quality of Brazilian pine tree seedlings in comparison to the other containers.