Background: Domestic cultivation under natural habitat may help to genetic diversity conservation and sustainable utilization of medicinal plant. Since alkaloids are nitrogenous compounds, the availability of nitrogen is expected to play an important role in the biosynthesis and accumulation of alkaloids in plants.

Objectives: The aim of this research was to study the effect of bio-fertilizer and chemical fertilizer on corm and colchicine yield in Colchicum kotschyi under natural habitat .

Methods: The experiment was performed in a randomized complete block design with eight treatments including of three levels of urea as nitrogen fertilizer (50, 100 and 150 kg ha^-1 ), three levels of Nitroxin (20, 40 and 60 L ha^-1 ), combined treatment (urea 100 kg ha^-1 + Nitroxin 40 L ha^-1 ) and no fertilizer as control with three replications at the natural habitat , during 2009 -2010.

Results: Results showed that the application of Nitroxin 40 L ha^-1 resulted in the highest corm dry yield (101.4 g), while the lowest corm dry yield was obtained in control (42.39 g). The yield of colchicin was higher in application of urea 100 kg ha^-1 (40.44 mg) or Nitroxin 40 L ha^-1 (37.58) than to other treatments, while the lowest colchicine yield was obtained in control (15.56 mg).