梁平柚果实膨大期叶片矿质营养诊断研究

【目的】对重庆地区梁平柚核心产区柚园进行营养诊断,为梁平柚的平衡施肥提供参考依据。【方法】以梁平柚核心产区18个代表性柚园为研究对象,通过测定果实膨大期叶片中氮(N)、磷(P)、钾(K)、钙(Ca)、镁(Mg)、锌(Zn)、铁(Fe)、铜(Cu)、锰(Mn)元素的含量,运用诊断综合施肥法(DRIS)对叶片营养状况进行研究。【结果】依据高产园叶片矿质营养元素含量范围确定梁平柚叶片矿质营养元素的适宜值为N(22.12±2.53)g/kg、P(0.77±0.20)g/kg、K(16.50±4.67)g/kg、Ca(29.13±6.12)g/kg、Mg(3.92±0.89)g/kg、Zn(18.45±3.07)mg/kg、Fe(128.26±34.00)mg/kg、Cu(20.66±5.68)mg/kg、Mn(20.98±9.70)mg/kg。不同供试柚园的养分需求顺序不同,高产园柚树相对缺乏元素有K、Mg、Fe、Mn、Cu,低产园柚树相对缺乏的元素有K、Mg、Fe、Mn。【结论】梁平柚园普遍存在缺K、Mg、Fe问题,尤其低产园柚树缺K、Mg问题较为突出,建议在生产上进行适当补充,以充分发挥果园的增产潜力。

Diagnostic study on mineral nutrition in leaves of Liangping pomelo during fruit expansion period

【Objective】This study aimed to provide a reference for nutrient diagnosis and balanced fertilization of Liangping pomelo orchards.【Method】The nutritional status of pomelo leaves of 18 representative orchards in the Liangping pomelo core production area was studied using diagnosis and recommendation integrated system(DRIS);the N,P,K,Ca,Mg,Zn,Fe,Cu,and Mn contents of pomelo leaves were determined during fruit expansion period,and the diagnosis standard of leaf nutrition was put forward.【Result】The average content of P,K,Mg,Cu in the leaves of high-yielding orchards was higher than that of low yield garden,and N,Ca,Zn,Fe,Mn were lower than that of low yield garden.According to the range of mineral nutrient content in leaves from high-yielding pomelo orchards,the appropriate values of mineral nutrient elements in Liangping pomelo leaves during fruit expansion period were as follows:N,(22.12±2.53)g/kg;P,(0.77±0.20)g/kg;K,(16.50±4.67)g/kg;Ca,(29.13±6.12)g/kg;Mg,(3.92±0.89)g/kg;Zn,(18.45±3.07)mg/kg;Fe,(128.26±34.00)mg/kg;Cu,(20.66±5.68)mg/kg;and Mn,(20.98±9.70)mg/kg.The order of nutrient requirement was different in different orchards;high-yielding pomelo orchards were relatively deficient in K,Mg,Fe,Mn,and Cu,whereas low-yielding pomelo orchards were relatively deficient in K,Mg,Fe,and Mn.The imbalanced index of nutrition in low-yielding pomelo orchards was higher than that in high-yielding pomelo orchards,which indicated that the imbalance of nutrition proportion was more serious in low yield pomelo garden,which was one of the reasons for the low yield of pomelo tree in low yield garden.【Conclusion】K,Mg,and Fe deficiencies are common in Liangping pomelo orchards,especially in low-yielding pomelo orchards.The results suggest that pomelo orchards should be appropriately supplemented with K,Fe,and Mg trace element fertilizer to improve their production potential.