. Arbuscular Mycorrhizal fungi and precursor feeding improve protein and trypthopan decarboxylase enzyme content in Cathaaranthus roseus L. Samaneh Rahmatzadeh1*, Jalil Khara1 and Seyed Kamal Kazemitabar2. Iranian Journal of Plant Physiology. 2012;2(3):455-459. 10.30495/ijpp.2012.540780