磷、钾营养对柑桔果实产量、品质和贮藏性的影响

Effects of phosphorus and potassium application on yield,quality,and storability of citurs fruits

采用田间试验以柑为材料研究了连续4年施用磷、钾肥后对柑桔果实的产量、品质和贮藏性的影响。结果表明,施用磷、钾肥,尤其磷、钾肥配施可显著提高柑桔果实的单果重和产量,以及采收时果实的可溶性固形物含量、可溶性糖含量、还原糖含量、糖/酸比和维生素C(Vc)含量,降低可滴定酸含量;并且可以有效地降低柑桔果实在贮藏过程中的失重率和烂果率,减缓糖分、酸度和Vc含量的下降。磷钾营养对于提高柑桔果实的耐贮性和维持贮藏过程中果实的风味和营养品质有一定的作用。

Phosphorus （P） and Potassium （K） are major important factors affecting citrus growth, yield and quality. Although the effects of P and K nutrition have well been documented for citrus trees in terms of fruit growth and yield, the influence of these two macronutrients on quality and storability of citrus fruits has not been fully elucidated. In the present study, a long-term field experiment was carried out for four years on Ponkan （ Citrus reticulata Blanco var. Ponkan） in order to determine the effects of P and K application on fruit yield, quality and storability of citrus grown in a red-soil orchard with low P and K concentrations. The experiment was set up in a incomplete factorial design with 7 treatments, with three yearly rates of P （P 0, 125 and 250 kg/ha） and K （K 0, 250 and 500 kg/ha） . The results showed that P or K, especially combined application of P and K greatly increased single fruit weight （62.93 to 114.11 g/fruit）, fruit yield （19923 to 48234 kg/ha）, content of soluble solids （12.2% to 13.3%） and soluble sugars （2.58% to 3.72%）, reducing sugar content （4.51% to 6.16 % ）, brix-acid ratio （2.84 to 5.15 ） and vitamin C content （37.52 to 44.91 mg/100g FW） of citrus fruits, and decreased titratable acidity （ 1.59% to 1.19% ） of citrus fruits. Furthermore, P and K supply effectively reduced weight loss of fruit, rate of fruit decay, and modified the decrease of sugar content, acidity and Vc of fruit during storage of citrus fruits. It suggests that applying P and K could increase yield and quality of citrus fruit and improve sensory and nutritive quality and storability of fruit during storage.