The study of drought stress and Bio fertilizer of nitrogen on some biochemical traits of Marigold medicinal plant (Calendula officinalis L.)

To determine the effects of drought stress and nitrogen bio-fertilizer on yield and biochemical indices of medicinal plant of Calendula (Calendula officinalis L.)، an experiment was carry out at research farm of Agriculture in Shahed University. This study was conducted using split plot design based on (RCBD) with three replications in2010-2011. The experiment factors including of different levels of drought stress at forth leaflet stages as main factor (applying soil water potential of 0. 5atm as Control((FC) field capacity)،soil water potential of 3. 5atm as moderate stress، soil water potential of 6. 5atm as highly severe stress،and applying soil water potential of 10atm as severe stress)and levels of nitrogen bio-fertilizer as sub factor were consist of (Control(no applying nitrogen bio fertilizer)، incorporation of 2Liter/ha nitrogen bio fertilizer with water irrigation and inoculation of 2Liter/ha nitrogen bio-fertilizer with seed treatment)، were considered in sub plots. The results showed that drought stress،nitrogen bio-fertilizer and its interaction had significant effect on all characters except for plant height and root weight (P<0. 01). In which with rising of drought stress، length roots (16%)، anthocyanins content (23%)، carotenoids content (71%)، and soluble sugars (36%)، proline content (47%) and photosynthetic pigments content (63%) increased. In that the greatest of flower yield and extract obtained in field capacity irrigation،and so under severe stress flower yield and the extract amount decrease to20%and50%respectively. The most of plant height،flower yield،photosynthesis pigments content،proline content and yield of flower extract were obtained when nitrogen of bio-fertilizer was used in case of seeding. Correlation coefficients showed that between flower yield with biochemical indices there were a meaningful negative correlations (P<0. 01). Overall results showed that Calendula can endure relatively high level of drought with applying 2liter of bio-fertilizer.