平和县琯溪蜜柚主产区果园营养状况及调控建议

从福建省平和县小溪、南胜、五寨、坂仔4个乡镇的琯溪蜜柚主产区果园采集30份柚子（以琯溪蜜柚白肉品种为主）果实及相应的土壤、叶片样品,测定分析了果实的品质及土壤、叶片养分含量指标。结果表明：超过半数果园土壤呈强酸性,pH<4.50;有机质含量处于适宜范围,速效磷含量过高,最大值为155.7 mg/kg;中微量元素（钙、镁、铜、锌、硼）含量普遍偏低,尤其是钙、镁,其含量均未达到丰富水平。果树叶片中全磷、铁、铜、硼含量偏高,其中磷和铁含量在30个调查果园中均高于适宜范围;钾、镁、锌含量则相反,最高含量分别为1.32%、0.22%、8.37 mg/kg,均属于缺乏状态。果实单果重范围为0.675~1.850 kg（除了2份葡萄柚样品）,且与土壤pH呈现正相关关系。可食率的差值为27.83个百分点,主要范围集中在75%~85%。固酸比差异较大,差值为12.35。Vc含量最大值为28.63 mg/100 g。综合该研究结果,建议当地果园减少磷肥及铜剂农药施用量,适当提高钾肥及钙、镁肥用量,提高土壤pH,促进肥料吸收利用,在保障果实品质的条件下减少环境污染。

Investigation on Nutrition Status of Guanxi Pomelo Orchards in Pinghe and Fertilization Suggestions

30 samples of grapefruit (mainly white variety of Guanxi pomelo), and corresponding samples of soil and leaves were collected from the representative fruit orchards of Xiaoxi, Nansheng, Wuzhai and Banzai in Pinghe, Fujian, and the quality of fruit and the nutrient contents of soil, leaf and fruit were analyzed. The results showed that more than half of the orchard soil samples were strongly acidic, pH < 4.50; the organic matter content was in a suitable range, but the available phosphorus content was too high, the maximum value was 155.7 mg/kg. The contents of medium and trace elements, especially calcium and magnesium, did not reach the rich level. The contents of total phosphorus, iron, copper and boron in the leaves were high, and the contents of phosphorus and iron in 30 orchards were higher than the suitable range. The contents of potassium, magnesium and zinc were the opposite. The highest contents were 1.32%, 0.22% and 8.37 mg/kg, respectively, which belonged to the state of deficiency. The single fruit weight ranged from 0.675 to 1.850 kg (except 2 grapefruit samples), and showed a positive correlation with soil pH. The difference of edible rate was 27.83%, and the main range was concentrated between 75% and 85%. The solid-acid ratio was quite different, with a difference of 12.35. The maximum Vc content was 28.63 mg/100 g. In general, it is suggested that local orchards should reduce the application of phosphorus fertilizer and copper pesticide, increase the application of potassium, calcium and magnesium fertilizer, to increase soil pH, promote the absorption and utilization of fertilizers, and reduce environmental pollution while ensuring fruit quality.