Nutrients are the second most important limiting factor after water in crop production. Nitrogen, phosphorus and potassium are the most required nutrients in crop production (Mengel and Kirkby, 2001). Therefore, enhancing efficiency and productivity of these nutrients can be regarded as an important management factor in crop production (Brussaard et al., 2007). Increasing nutrient efficiency, not only reduces environmental pollution but also improves economic incomes for farmers (Rathke et al., 2006). Capture efficiency is the ratio of nutrient uptake to the available nutrient (Cassman et al., 2002; Brussaard et al., 2007; Tittonell et al., 2007). Capture efficiency of nitrogen for cereals have been reported to be 33% worldwide, which is 42% for developed countries and 29% for developing countries (Raun and Johnson, 1999). Nutrient use efficiency is the ratio of seed yield to the amount of nutrient in the above ground parts of plant (Rathke et al., 2006). Tittonell et al. (2007) described nutrient use efficiency as dry matter produced (Kg) by each Kg of nutrient uptake. The minimum and maximum amount of nutrient use efficiency for corn has been reported to be 30-70 Kg per Kg nitrogen, 200-600 Kg per Kg phosphorus and 30-130 Kg per Kg potassium (Janssen, 1998). Nutrient productivity is the amount of biomass produced per unit of available nutrient (An et al., 2005). Rathke et al. (2006) calculated nitrogen productivity as seed yield per amount of nitrogen applied. Nutrient productivity is the product of capture efficiency and use efficiency (Cassman et al., 2002). Morris and Garrity (1993) reported in intercropping, average of phosphorous and potassium uptake increased 43 and 35 percent compared to sole cropping, in turn. Root system is extensive in intercropping and it is possible to uptake immobile nutrients like phosphorous and potassium from larger area. In Gunes et al. (2007) study, legume species increased phosphorus availability for wheat and it was shown by increasing in wheat yield and enhancing in phosphorus concentration in above ground part of wheat plant, too. Legumes in intercropping with grass, provide large amount of nitrogen needed for grass. In Ghosh et al. (2006) study, activity of Nitrate-reductase enzyme which is necessity for optimum use of soil nitrogen and also chlorophyll amount in sorghum in intercropping was more than that in sole cropping. With consideration to ecological and agronomic importance of intercropping systems, this experiment was conducted for examining of intercropping and sole cropping of three crops including rapeseed, bean and corn with a view to investigation of nutrient efficiency in terms of capture, use and also productivity for the main plant nutrients of nitrogen, phosphorus and potassium.

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