Leaf nutrient concentration, yield, production efficency, juice quality and nutrimental indexes on Valencia orange grafted on citrus rootstocks

摘要

In Colima, Mexico, 50% of the citrus are grown on sandy loam and sandy soils. During 2001, sixteen citrus rootstocks were evaluated to determine the foliar nutrient concentration, yield, fruit quality and nutritional indexes of Valencia sweet orange (Citrus sinensis L.) trees at eight years from planting. Treatments (rootstocks) were lemons, citranges, mandarins, limes and trifoliate; the control treatment was sour orange (Citrus aurantium L.). Foliar concentrations of N, P, K, Ca, Mg, Fe, Mn and Cu were determined; Kenworthy indexes were calculated on the basis of tree vigor, yield, fruit quality and yield efficiency (kg m(-3) of foliage). Nutrient concentrations depended on the rootstock efficiency for the uptake of specific nutrients. Volkameriana (Citrus volkameriana Pasq.) accumulated less Mg, while sour orange was the least efficient in the absorption of P. Cleopatra (Citrus reshnixTan), Carrizo (Poncirus trifoliate (L.) Raf.xC. sinensis L.) and SunkixTrifoliate (SunkixP trifoliate) had the lowest K concentration. The ratio K(Ca+Mg) depended on the rootstock used: Macrofila (Citrus macrophylla Wester) had the highest value and Cleopatra the lowest. Amblicarpa (Citrus amblycarpa Ochsc) showed values of nutrimental sufficiency in spite of its great vigor (tree canopy). Fruit yield depended on tree vigor (canopy diameter). Kenworthy nutritional balance index was N=2.8%, P=0.33%, K=0.86%, Ca=3.18%, Mg=0.72%, Mn=3340 mg kg(-1) and Cu=40 mg kg(-1).