| 【Objective】This study was to explore the effects of partial substitution of chemical fertilizers with
different organic and inorganic fertilizers on fruit yield and quality of Citrus reticulata Tankan and soil nut rients, and to
provide practical ba sis for reducing chemical fertilizer and improving quality and efficiency of Tankan.【Method】A field
experiment was conducted, with chemical fertilizers as control（CK）, the substituting chemical fertilizer experiments with
organic-inorganic mixed fertilizers were set up in a total of five fertilization treatments, including two calcium-magnesia phosphate fertilizer groups（F1 and F2）and two groups without calcium-magnesia phosphate fertilizer（F3 and F4）, then
the responses of Tankan yield, fruit quality and soil nutrients to different fertilization treatments were compared.【Result】
Compared with conventional chemical fertilizer, the organic-inorganic mixed fertilizer substituting chemical fertilizer
（16.67%, 33.33%, 58.33% and 75%）could enhance soil pH value, organic matter and alkaline hydrolytic nitrogen contents,
increase the Tankan yield by 4.4%-12.1%, improve the contents of soluble solids, total sugar, vitamin C and the sugar-acid
ratio, and reduce the total acid content. When applying equal amount of organic-inorganic mixed fertilizer（equal amount of
chemical nitrogen）, the treatments of F3 and F4 without calcium-magnesia phosphate fertilizers significantly reduced soil
available phosphorus, calcium and magnesium contents, and the Tankan production declined but still with an increase by
9.0% and 4.4% compared to CK, while the groups of F3 and F4 could more effectively improve the soil pH, organic matter
and alkali solution nitrogen contents and the fruit quality indexes, and the effect of treatment F3 was better than that of F4.
【Conclusion】Organic-inorganic mixed fertilizer substituting chemical fertilizer is an effective measure to reduce the amount
of chemical fertilizer and increase the efficiency in Citrus reticulata Tankan orchard. Considering the yield, quality and cost, at
present, it is feasible to reduce the input of calcium-magnesia phosphate fertilizer in the test area, and 50% organic nutrients
substituting inorganic nutrients（including calcium and magnesium）is a proper replacement ratio for fertilization. |
