Planta Med 2008; 74 - P-5
DOI: 10.1055/s-2008-1075201

Shade, Irrigation and Fertility Effects on Biomass Production and Flavonoid Content in American skullcap

A Similien 1, DA Shannon 1, CW Wood 1, WG Foshee 2, BW Kemppainen 3, N Joshee 4, AM Rimando 5
  • 1Department of Agronomy and Soils, Auburn University,Auburn Alabama 36849, USA
  • 2Department of Horticulture, Auburn University, Auburn Alabama 36849, USA
  • 3Department of Anatomy, Physiology and Pharmacology, Auburn University, Auburn Alabama 36849, USA
  • 4Agricultural Research Station, Fort Valley State University, 1005 State University Dr. Fort Valley, GA 31030, USA
  • 5USDA Agriculture Research Service, Natural ProductsUtilization Research Unit University of Mississippi, USA

American skullcap (Scutellaria lateriflora), native to moist habitats in eastern North America, is valued for medicinal properties associated with the flavonoids, scutellarin, baicalein and baicalin. Information on how growing conditions affect the yield and concentration of these flavonoids is lacking. A 2 × 2 × 3 split plot factorial experiment was established in Shorter, Alabama to determine the effects of growing conditions on biomass yield and flavonoid content. Treatment factors were shade (40% shade vs. no shade), irrigation (applied at 30 kPa vs. no irrigation) and nutrients (no fertilizer vs. fertilizer (100 kg N, 68 kg P, 42 kg K ha −1) and chicken litter (100 kg N, 50 kg P and 123 kg K ha −1). The shade factor formed the main plot units while irrigation and nutrient factors were randomized within subplots. Seedlings were transplanted to field on April 30, 2007. Shoots were harvested at full bloom on June 29 and September 5 2007. At first harvest, shade did not affect yield, but increased height by 33% and decreased percent dry matter by 14.5%. Irrigation increased yield by 23.7%, height by 12.7% and decreased percent dry matter by 8.3%. Nutrient application increased yield by 45.7% and height by 9.9%. At second harvest, shade increased yield by 63.4%, height by 52.3% and decreased percent dry matter by 22.6%. Irrigation had no effect. Nutrient application increased yield by 10.4%, decrease height by 2.1% and percent dry matter by 5.5%. The effect of growing conditions on flavonoids concentration will also be presented.