Effect of low irrigation and use of phosphate solubilizing bio-fertilizer on yield and yield components of safflower (Carthamus tinctorius L.)

To investigate the effects of low irrigation and use of phosphate solubilizing bio-fertilizer and drought stress on yield and yield components of safflower, an experiment was conducted as a factorial experiment based on randomized complete block design with three replications in 2012 in Alborz Province (Mahdasht city). In this study, the low irrigation factor at four levels: control (optimum irrigation), low irrigation at flowering, low irrigation at fruiting and low irrigation during tow stages and phosphate solubilizing bio-fertilizer factor at four levels: control (no application), seed coated, foliar spray and combined application (seed coated and foliar spray )was considered. Based on the results of the analysis, each of the factors of low irrigation and bio-fertilizer except for harvest index had significant effect on all traits at the 1% level. The lowest traits amounts was observed in drought stress at flowering and fruiting and the highest traits amounts was obtained in no drought stress condition. Bio-fertilizer caused to increase of yield and yield components of safflower when the fertilizer applied in both foliar application and seed coated than the others.According to interaction effects not only application of bio fertilizer cause to increase yield and yield component but also cause to improve more traits under drought conditions.