摘要 : A survey of plantation-grown Cyclopia subternata showed that average concentrations of nitrogen, phosphorus, potassium, calcium and magnesium in the new top growth of mature seedlings and cuttings were 1.59, 0.09, 0.62, 0.32, and ... 展开 A survey of plantation-grown Cyclopia subternata showed that average concentrations of nitrogen, phosphorus, potassium, calcium and magnesium in the new top growth of mature seedlings and cuttings were 1.59, 0.09, 0.62, 0.32, and 0.17%, respectively. Respective removal rates of these elements at each harvest averaged 13.1, 0.7, 5.1, 2.6, and 1.4 g plant-1. These quantities were equivalent to. 28% to 45% of the total element in the plant. Concentrations in the top growth of sodium, manganese, iron, copper, zinc and boron averaged, respectively, 1459, 34, 143, 7, 9, and 30 mg kg-1. Old top growth dry mass and root dry mass increased with time. Peak new top growth yields from C. subternata plants derived from seedlings and cuttings differed by only 2.2%. At peak production, new growth constituted 15% of total seedling dry mass and 21% of total cutting dry mass. 收起