‘马来西亚1号’菠萝蜜叶片氮磷钾动态的研究

Dynamics of Nitrogen,Phosphorus and Potassium Nutrients in the Leaves of‘Malaysia No.1’Jackfruit

通过对海南省文昌市南阳镇、琼海市大路镇、乐东县黄流镇3个地区‘马来西亚1号’菠萝蜜叶片氮、磷、钾3种营养元素的周年变化规律跟踪调查分析,结果表明:3个地区菠萝蜜叶片营养元素变化规律相似。元素年平均含量表现为氮>钾>磷。根据实际生产中的生育期调研分析,将菠萝蜜的生长周期大致划分为2个批次3个时期:第一批次养树期(11—12月)、花芽分化期(1—2月)、结果期(3—4月);第二批次养树期(5—6月)、花芽分化期(7—8月)、结果期(9—10月)。生长周期内,氮元素含量年变化呈现“N”字型变化趋势;磷含量在1—4月呈先上升后下降的趋势,随后呈缓慢上升趋势;钾含量变化趋势与氮含量变化相似,但钾元素含量变化没有氮元素变化明显。菠萝蜜叶片中大量元素含量的适宜范围为:全氮21.03~22.15 g/kg,全磷2.86~3.40 g/kg,全钾13.49~14.47 g/kg。在生长发育过程中,菠萝蜜需氮、钾元素较多,特别是在花芽分化期和结果期,应注意增施氮肥与钾肥,磷肥应于养树期施足。

The annual changes of nitrogen,phosphorus and potassium in the leaves of‘Malaysia No.1’jackfruit in three locations in Hainan were similar.The annual average content of elements was N>K>P.According to the investigation of the growth period in actual production,the growth cycle of jackfruit is roughly divided into two batches and three stages,the first batch of tree growing stage(November to December),the first batch of flower stage(January to February),the first batch of fruit stage(March to April),the second batch of tree growing stage(May to June),the second batch of flower stage(July to August),the second batch of fruit stage(September to October).During the growth cycle,the annual variation of nitrogen content showed a trend of“N”shape.From January to April,the phosphorus content increased first and then decreased,and then increased slowly.The variation trend of potassium content was similar to that of nitrogen content,but the variation trend of potassium content was not as obvious as that of nitrogen content.The optimum range of abundant elements in the leaves of jackfruit was N 21.03–22.15 g/kg,P 2.86–3.40 g/kg,K 13.49–14.47 g/kg,respectively.The growth and development of jackfruit require more nitrogen and potassium elements,especially in the flower and fruit stages,so attention should be paid to increasing the application of nitrogen and potassium fertilizer,and sufficient phosphate fertilizer should be applied at the tree growing stage.