Study on Pyrethrin Content in Pyrethrum Flower Head at Different Stages of Development

Abstract

The "pyrethrin" content of Pyrethrum (Chysanthemum cinerariaefolium) flower heads at seven stages of development were measured. The results showed that pyrethrins content varied between 0.38-1.87 percent by weight. It reached the highest level at the fifth stage when 40-50% of florets or 3-4 rows of disc floret are open. Thereforn, picking flower only at the "correct" stage of maturity should be considered.