study the role of some macroelements on corm yield and colchicine content in colchicum kotschyi boiss. (colchicaceae) under soilless culture conditions

abstract colchicum kotschyi boiss (colchicaceae) is one of the sixteen iranian native colchicum species, containing considerable amount of colchicine. to study the effect of different nutrient levels on corm yield and colchicine content of colchicum kotschyi boiss under open field soilless culture, an experiment was performed in a randomized complete design at the horticultural research station of horticultural department of ferdowsi university of mashhad, during the 2008-2009. treatments were three nutrient solutions (included; ι: 100, 60, 150, 105, ιι: 150, 67, 200, 158 and ιιι: 200, 75, 260, 250 ppm for n, p, k and ca respectively) with three replications (5 samples per replication). the uniform corms were collected from the wild in august and planted in pots, containing 50% cocopit + 50% perlite, in open field in september and fed by different nutrient solutions. the highest and the lowest fresh and dry yield of corm observed in plants treated by nutrient solutions ιιι and ι, respectively. maximum and minimum of corm dry matter percent, amount of colchicine in per gram of dry matter and total yield of colchicine observed in ιι and ι nutrient treatments, respectively, were found to be 28.4%, 0.533 mg/g dry matter, 7.04 mg and 23%, 0.264 mg/g dry matter and 2.407 mg, respectively. the results indicated that the best yield of colchicine resulted from the solution of ιι including 150, 67, 200, 158 ppm for n, p, k and ca, respectively comparing to other treatments.