关键词: 甜橙, 三峡库区, 叶片, 营养元素, 丰缺状况

Key words: Knowing leaves nutrient status is a basis to formulate a suitable fertilization strategy. Orange leaf samples aged four to six months collected from 200 orange orchards in 5 main producing counties were analyzed to learn the leaves nutrient status of the Three Gorges area in Chongqing. The results showed that the tested leaves suffered sharp nutrients imbalance. N and Fe content were very high, P, Zn, and Mo content were appropriate, K, Ca, Mg, Cu and Mn content were respectively low and B content was at a serious shortage. N, P, K, Ca, Mg, Fe, Cu, Mn, Zn, B and Mo were respectively in the average content of（27.34 ± 5.92）, （1.40 ± 0.21）, （11.00 ± 3.04）, （25.27 ± 8.53）, （3.34 ± 0.89） g · kg^-1, （125.00 ± 40.55）, （5.38 ± 2.59）, （33.69 ± 6.33）, （34.30 ± 17.91）, （23.68 ± 14.24）, and（0.79 ± 0.49）mg · kg^-1. N and Fe content in and above high volume were at the rate of 39.5% and 53.0%, P, Zn, and Mo content in appropriate range were at the rate of 75.5%, 83.5% and 70.5%, K, Mn and Mg content in low volume were 50.3%, 37.5% and 20.0%. B, Ca, K, Cu in and below low volume were at the rate of 76.5%, 64.0%, 57.3% and 51.0%. In the view of nutrients dificiency, the orange production in this area required considerable increased B, and Ca and K fertilization is needed for the orchards with low leaf Ca and K content, to balance the orange nutrients.