‘红美人’柑橘结果树的营养需求特征研究

Nutrition demand characteristic of fruit-bearing tree of‘Hongmeiren’citrus

通过对柑橘品种‘红美人’果树叶片、果实养分含量及产量进行分析,明确柑橘结果树养分吸收特征。结果表明:开花期和果实膨大期是‘红美人’柑橘对氮、磷、钾养分需求的关键时期,叶片中氮、磷含量在开花期最高,而钾在果实膨大期含量最高;叶片中钙、硼含量呈现先升高后降低的趋势,分别在成熟期和幼果期达到最大值;而镁的含量变化不大,仅在花芽分化前期略有增加然后减少。根据柑橘果实产量、养分含量和肥料利用率等指标,估算出其产量在23 250 kg∕hm^(2)时合理施肥量为:N 324.2—405.3 kg∕hm^(2)、P2O5230.3—345.4 kg∕hm^(2)、K2O 343.3—457.7 kg∕hm^(2)。

The trend of nutrient concentration in leaves,the yield and nutrient concentration of fruit were determined and analyzed in this research so as to make a clear understanding of the‘Hongmeiren’citrus nutrient uptake.Results indicated that flowering and fruit swelling stages were the key periods of nutrient uptake for‘Hongmeiren’citrus.The highest concentrations in leaves for N and P occurred in the flowering stage respectively,and the fruit swelling stage had the highest concentration for K.The concentrations of Ca and B in leaves increased first and then decreased,and peaked in the mature and the young fruit stages respectively.The concentration of Mg in leaves did not change much from flowering to mature stage,but increased and then decreased at flower bud undifferentiation stage.The annual suitable nutrient input for N,P and K at the yield level of 23250 kg∕hm^(2) were 324.2—405.3 kg N∕hm^(2),230.3—345.4 kg P2O5∕hm^(2),343.3—457.7 kg K2O∕hm^(2),