Farhad Azarmi-Atajan - Department of Soil Science and Engineering, Faculty of Agriculture, University of Birjand, Birjand, Iran.
Mohammad Hassan Sayyari-Zohan - Department of Soil Science and Engineering, Faculty of Agriculture, University of Birjand, Birjand, Iran.

Purpose: Considering the role of nutrient supply in plant growth, the effect of single and simultaneous application of triple superphosphate (TSP) and phosphate solubilizing bacteria (PSB) on the growth and phosphorus uptake of pistachio seedlings were investigated. Research method: A study was conducted as a factorial experiment based on a completely randomized design with three replications under greenhouse conditions. The treatments include three levels of PSB [Control (PSB۰), Pseudomonsa sp. (PSB۱) and Pseudomonas fluoresens (PSB۲)] and three levels of P [Control (P۰), ۱۵ mg P kg-۱ soil (P۱) and ۳۰ mg P kg-۱ soil (P۲) as triple superphosphate]. Findings: the results indicated that application of TSP and PSB increased dry weight, plant height, total chlorophyll and carotenoids content and uptake of P in pistachio seedlings. Inoculation with PSB increased shoot dry weight (۳۶%), root dry weight (۴۴%), total chlorophyll (۳۱%), carotenoids (۳۰%), shoot P uptake (۶۲%) and root P uptake (۸۴%) in pistachio seedlings. Research limitations: By measuring other traits such as nutrient concentration, the response of pistachio seedlings to microbial inoculation can be more clearly interpreted. Originality/Value: Using of new insecticides with new and widespread mode of action can be recommended against postharvest pest in the practical entomology.

Calcareous soil, Nutrient status, Phosphorus sources, Photosynthesis, Rhizobacteria