The experiment was conducted to evaluate the nutrient utilization ability of sweet orange (Citrus sinensis L. Osbeck) budded on five rootstocks (viz., Sathgudi, Rangpur lime, Cleopatra mandarin, Troyer citrange, and Trifoliate orange) in Alfisols at the experimental farm of the Citrus Improvement Project, S. V. Agricultural College Farm, Tirupati, Andhra Pradesh, India. Results of the study revealed that all the five rootstocks showed differential behaviors in terms of nutrient absorption from the soil. Rootstocks exhibited significant variation in the leaf content of potassium (K), copper (Cu), manganese (Mn), and boron (B) at all the three stages of sampling. Concentrations of the following key nutrient elements significantly varied: phosphorus (P), calcium (Ca), magnesium (Mg), zinc (Zn), and Cu at stage 1; K, Ca, Mg, Zn, iron (Fe), and Mn at stage 2; and nitrogen (N), P, Zn, Fe, and B at stage 3. The performances of rootstocks in terms of relative nutrient accumulation indices (RNAIs) were in the order of Sathgudi (1.00) > Rangpur lime (0.98) > Cleopatra mandarin (0.96) > Trifoliate orange (0.76) > Troyer citrange (0.69). The present study clearly demonstrated that citrus rootstocks employed had differential nutritional behavior and different abilities to utilize plant nutrient elements. Thus, the findings of the present study and the methodology adopted can help the horticultural breeders and nutritionists choose the best rootstock/scion combination having the desirable traits of nutrient utilization ability and also to plan effective fertilizer schedule programs for achieving greater yields.
