Effects of Sucrose and Other Additives on In Vitro Growth and Development of Purple Coneflower (Echinacea purpurea L.)

Echinacea purpurea (purple coneflower) is being used for the preparation of more than 240 extracts, salves, and tinctures to help cure diseases like rabies, cold, and upper respiratory infections. Hence, efforts were made to develop a culture medium for successful in vitro culturing of cornflower and to regenerate buds and induce roots to enable mass propagation of selected clones. Of the three levels of sucrose tested as a supplement to MS media (Murashige and Skoog’s medium, 1962) 3% showed better rooting of buds and appeared morphologically normal and identical as compared to those grown at higher and lower concentrations (2 and 4%). The additives hydrolyzed lactabumin (0.0, 100, 300, and 900？mgL？1), peptone (0.0, 100, 300, and 900？mgL？1), and yeast (0.0, 100, 300, and 900？mgL？1) to media containing 0.3？mgL？1 BA (6-benzyladenine) and 0.01？mgL？1 NAA (naphthaleneacetic acid-plant growth regulators) has negatively influenced proliferation of shoots. The higher concentrations of the above have delayed the development of plantlets. Shoot multiplication was enhanced by coconut water with 2% being the best among 4 and 8% tested. Shoot organogenesis was not influenced by copper sulphate (0, 1.5, 3, 6, and 12？mgL？1) and silver nitrate (0.0, 0.5, 2.5, and 12.5？mgL？1) supplements and at higher concentrations of the above inhibited plant growth. 1. Introduction Large-scale in vitro propagation medicinal plants have become vital to meet the increasing demand for high-quality pharmaceuticals and for the conservation of valuable elite stock plants [1–4]. Echinacea purpurea (purple coneflower) is known to contain carbohydrates, glycosides, alkaloids, alkylamides (alkamides), polyacetylenes, fatty acids, essential oil, and phytosterols and is being used for the preparation of more than 240 extracts, salves, and tinctures to help cure diseases like rabies, cold, upper respiratory infections, and so forth (http://www.bioalma.com/). Hence, efforts were made to develop a culture medium for successful in vitro culturing of cornflower and to regenerate buds and induce roots to enable mass propagation of selected clones. 2. Materials and Methods 2.1. Plant Source Seeds for the present study were harvested from the purple cornflower clone (source: Norton, MA, USA) maintained at the Chinese Medicinal Plant Garden, South China Agricultural University. 2.2. Establishment of Aseptic Seedlings Seeds were surface-sterilized by sequentially immersing in 70% ethanol for 1 minute, 0.1% mercuric chloride for 10 minutes, and 1% sodium hypochlorite (containing Tween 20, one drop per