奉节脐橙树体营养状况研究

为了解重庆三峡库区脐橙树体营养状况，以主产区奉节县为代表，2010-2013年期间对该县7个主产乡镇的191个脐橙园的当年生春梢营养枝叶片进行了营养元素含量分析。结果表明，树体营养元素失衡较严重，从叶片大中量营养元素看，叶片N含量充足且以过剩（偏高或过量，下同）为主，其过剩比例为58.11%；P含量以适宜和偏高为主，其比例分别为59.16%和31.94%；K含量以偏低为主，其含量不足（缺乏或者偏低，下同）的比例为56.03%。Ca含量以适宜和过剩为主，其比例分别为62.83%和30.89%;Mg和S含量不足的比例分别为31.94%和26.70%。从叶片的微量元素来看，叶片Fe元素含量最为丰富，其含量不足的比例仅5.76%;Mn和B处于适宜范围的果园比例也较高，分别为70.68%和62.07%；叶片Zn含量最为缺乏，含量不足的比例高达82.20%（缺乏比例达54.97%）；叶片Cu含量不足的果园也较高，占51.84%。奉节脐橙树体存在严重的Zn含量不足，生产上应该重视补充Zn肥，适量补充K、Mg和Cu肥，以满足柑桔营养平衡施肥。

Leaf Nutrient Status of Navel Orange in Fengjie, Chongqing

In order to investigate the leaf nutrient status of navel orange trees in the Three Gorge Reservoir Area in Chongqing, leaf samples collected from 191 navel orange orchards in 7 main producing towns in Fengjie county of Chongqing city were analyzed. Results showed that the tested orchards suffered leaf nutrient element imbalance. N content was rich and 58.11% samples were in surplus (high or excess) range. P content in 59.16% samples was optimum and in 31.94% samples was high. K content in 56.03% samples was shortage (below the optimum range). Ca content in 62.83% and 30.89% samples was optimum and surplus, respectively. 31.94% and 26.70% leaf samples showed Mg and S shortage, respectively. As to the leaf microelements, Fe content in most samples was rich and only 5.76% of them showed shortage. Mn content in 70.68% samples and B content in 62.07% samples were in optimum range. Most orchards (82.20% leaf samples) suffered Zn shortage and 54.97% of them were Zn deficiency, and 51.84% samples were Cu shortage. Navel orange orchards in Fengjie county should be attached importance to the application of balance nutrient elements such as K, Mg, Zn and Cu .