BACKGROUND: Fertilizer management is one of the most important factors in successful cultivation of crops affecting yield quality and quantity. Growth analysis is still the most simple and precise method to evaluate the contribution of different physiological processes in plant development. OBJECTIVES: Current research was conducted to evaluate effect of different level of Phosphorous biofertilizer and micro elements (Boron and Manganese) on physiological parameters of Alfalfa. METHODS: This research was carried out in three farm (One-year, three-year and five-year hay fields) according combined analysis factorial split plot experiment based on randomized complete blocks design during two year (2012-2013) with three replications. This experiment was performed on alfalfa planted at different years (one year, three years and five years). The main factor included phosphorous biofertilizers (p < sub>0: control, p < sub>1: Adding the bacteria at the rate of 100 g per 400 liters of water and the sub factor consisted Manganese fertilizer (Mn0: control, Mn1: Foliar application of chelate at the rate of 1 L.ha-1, Mn2: soil application in source of manganese sulfate at the rate of 10 kg.ha-1) and Boron fertilizer (B0: control, B1: Foliar application at the rate of 1 L.ha-1, B2: soil application at the rate of 10 kg.ha-1). RESULT: Compare different level of treatments revealed the highest amount of physiological parameters belonged to TR14: p < sub>1B1Mn1 and TR15: p < sub>1B1Mn2 and the lowest one were for TR1: p < sub>0B0Mn0 treatment in three farms (One-year, three-year and five-year hay fields). CONCLUSION: Finally according result of current research revealed applying studied elements significantly increases crop production and can be suggested as the best nutritional recommendation for alfalfa so consume phosphorus biofertilizer, Foliar application of boron with soil application and foliar application of manganese had highest amount of physiological parameters such as LAI, CGR, NAR and RGR. Manuscript profile