Field experiment was conducted at the Teaching and Research Farm, Federal University of Agriculture, Abeokuta to evaluate the influence of fertilizer types/rates on attainment of budding size responses of Citrus reticulata var Cleopatra mandarin. Three months old Citrus seedlings were treated with Phosphorus at three rates of 0, 12.5 and 25kg/ha single super phosphate (SSP) and Nitrogen at seven rates of 0, 12.5, 25 and 50kg/ha NPK with additional N rates at 12.5kg/ha NPK + 12.5kg/ha urea, 25kg/ha NPK + 12.5kg/ha urea and 50kg/ha NPK + 12.5kg/ha urea arranged in a completely randomized design replicated three times. The results showed that there was no significant difference in Nitrogen application rates. However, with exception of no significant difference in leaf area at 2 8 weeks after transplanting (wap), significantly (p<0.05) higher response of Citrus was observed for P at 25kg/ha SSP but not different from unfertilized control (0kg/ha). The lower growth and nutrient uptake responses observed for P at 12.5kg/ha SSP could be due to the effect of nutrient antagonism. Interaction effects between P and N occurred only for plant height at 14 wap and stem girth at 10 and 14 wap. In summary, while P influenced growth better than N indicating that higher rates of N might be needed to improve seedling growth of Citrus in nursery, Citrus plants responded differently to fertilizer P and N application rates.
Citrus reticulate var Cleopatra mandarin, Fertilizer types, Fertilizer rates, Nutrient uptake, Seedlings, Growth