Plant nutrition, growth and polygodial production of Tasmannia lanceolata

Rapid growth of some native Australian plant species can be achieved by targeted applications of selected nutrients. The aim of this study was to examine the influence of nutrient levels on early establishment of Tasmannia lanceolata (Winteraceae) for potential plantation production of polygodial extract from leaves. Treatments of a comprehensive fertiliser on a single clone of T. lanceolata were imposed in a pot trial with a factorial design. Measurements of plant height, leaf number and stem diameter were made over a 40-week period to evaluate plant growth performance. Leaf mineral nutrient composition and plant extract quantity and quality were measured. Greatest change in plant height of 553.1 mm was achieved at the highest fertiliser rate of 12 g pot^-1 but not greatest leaf number or stem width. The lowest fertiliser rate produced a significantly higher extract yield on a dry matter basis than higher fertiliser treatments, but significantly lower plant growth. Polygodial yield as a proportion of oil yield was unaffected by fertiliser rate. The outcomes of this trial will inform field nutrition requirements to optimise the balance between gross production and polygodial concentration.