Which medium is specially designed for woody plants?
Woody Plant Medium WPM specially formulated by Lloyd and McCown in 1980 to meet nutritional demands of woody trees shrubs and hard to culture species which exhibit ammonium toxicity tip necrosis and vitrification on high salt MS medium. WPM lowers total nitrogen to roughly one quarter of MS, ammonium nitrate 400 mg per L versus 1650, calcium nitrate increased to improve lignification and middle lamella stability, potassium sulfate replaces potassium nitrate at lower level to reduce hyperhydricity, and microelements adjusted copper sulfate elevated for lignin biosynthesis polyphenol oxidase. It
Ref: Lloyd & McCown Int Plant Prop Soc 1980 WPM; NCBI woody plant medium formulation.
