effect of biofertilizers application on some morphological characteristics and yield of dragonhead (dracocephalum moldavica l.)

abstract in order to evaluate the effects of biofertilizers on yield and morphological characters in dragonhead, an experiment based on randomized complete block design with four replications was conducted in 2008. treatments were nitroxin, biological phosphorus, biosulfur, nitroxin+biological phosphorus, biological phosphorus+ biosulfur, nitroxin+ biosulfur, nitroxin+biological phosphorus+ biosulfur, chemical origin of nitrogen+ phosphorus+ potassium and control. the results showed the effects of treatments on stem diameter, the number of flowers, the number of branches and leaves, plant dry weight and biological yield of dragonhead were significant. the highest number of branches (10) observed in nitroxin+biological phosphorus treatment. the greatest number of flowers (43) and leaves (2475), stem diameter (0.76), dry weight (28.8 gr), and biological yield (6150 kg/ha) were obtained from chemical fertilizer, althought there was no significant difference between nitroxin and chemical fertilizer. it seems that application of nitroxin could result an optimum yield of dragonhead compared to npk, without harmful effects assigned to chemical fertilizers due to environmental and health issues.