Horticultural and Biochemical Variations Due to Seed Source and Production Methods in Three Echinacea spp.

Abstract

We evaluated 4 years of organically produced Echinacea angustifolia, E. purpurea, and E. pallida, comparing commercial organic seed source against public germplasm and open-field production against screened cages to prevent leafhopper transmission of aster yellows. Both seed sources produced excellent root yields, with fourth-year E. angustifolia yield, at 1,504 kg ha−1, greater in the open field than under screened cages. Yields were equivalent across E. purpurea treatments, averaging 4,845 kg ha−1. E. pallida yield, at 8,510 kg ha−1, was greater under screened cages. Open-field Echinacea plants experienced more disease than those under screened cages. Cichoric acid, chlorogenic acid, and echinacoside levels were acceptable across all treatments. Alkamides 8 + 9, associated with immune-modulating effects, increased over the years.