西瓜钾素吸收特征及钾肥施用优化机制  

Absorption character of potassium and optimization mechanism of potassic fertilization on watermelon

作　　者：董亚 王硕 吴萍 陆海燕 周世品 董彩霞 任丽轩 

机构地区：[1]南京农业大学资源与环境科学学院/农业部长江中下游植物营养与肥料重点实验室/江苏省有机固体废弃物资源化协同创新中心,江苏南京210095 [2]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,江苏南京210008

出　　处：《南京农业大学学报》2018年第1期98-104,共7页Journal of Nanjing Agricultural University

基　　金：国家重点研发计划项目(2016YFD0200106);江苏省自然科学基金项目(BK20151432);国家公益性行业(农业)科研专项(201203013);土壤与农业可持续发展国家重点实验室项目(Y412201438)

摘　　要：[目的]钾肥管理是西瓜生产的关键因素,对提高经济效益和维持生态环境可持续性具有重要意义,本文旨在研究西瓜的钾素吸收特征及钾肥优化施用的机制。[方法]采用田间试验方法,研究钾肥不同施用水平下西瓜各生育期的干物质量、钾素吸收量、钾素吸收速率以及西瓜的产量与品质。[结果]西瓜对钾素的吸收量与西瓜干物质量、产量和品质存在正相关关系。西瓜在不同生育期对钾肥水平的反应不同,幼苗期对钾肥最敏感,基肥施用量为90 kg·hm^(-2)K_2O时,西瓜根、茎、叶中的钾含量最高,施用量高于180 kg·hm^(-2)K_2O时,西瓜叶中的钾含量低于对照;在膨果期,钾肥追肥量为180 kg·hm^(-2)时西瓜钾素吸收速率最大,该时期的钾素吸收量占全生育期吸收量的67.9%;在成熟期,450 kg·hm^(-2)K_2O水平下西瓜叶片中钾含量最高,600 kg·hm^(-2)K_2O水平下果实皮和瓤中的钾含量最高。钾肥施用量为300 kg·hm^(-2)时,西瓜干物质积累量最大,钾素总吸收量最高,此时西瓜产量最高,且可溶性糖含量最高。[结论]西瓜钾肥施用的最佳方案为基肥施用90 kg·hm^(-2),坐果期追肥180 kg·hm^(-2),基肥和追肥的比例为1∶2。[ Objectives] Potassium fertilizer management is the key factor of watermelon production. It is significant on the improvement of agricultural economic efficiency and the development of sustainable ecological environment. [ Methods ] Field experiment was carried out to investigate dry matter, potassium absorption and absorbing rate, as well as the yield and quality on different levels of potassium fertilizer management on watermelon. [ Results ] Dry matter, yield and quality of watermelon were positively relative with potassium absorption. Watermelon growth responded to potassium fertilizer on each growing period. Dry matter and potassium content was sensitive to potassium fertilization at seedling stage. Potassium content in root, stem and leaf was the highest at 90 kg-hm-2 K20 fertilization. They were lower in leaf in more than 180 kg.hm-2 K20 treatments than that in control. In fruit expanding period,the potassium absorp- tion rate was the highest at 180 kg.hm-2 K20 level fertilization. The potassium absorption in this period was 67.9% in the plant growing period. In mature period,potassium content in leaf was the highest at 450 kg.hm 2 K2O level fertilization. The potassium content was the highest in both rind and flesh at 600 kg·hm-1 K2O level fertilization. Biomass of watermelon was the highest on 300 kg.hm-2 K2O among all levels of potassium fertilization, as well as potassium absorption, yield and soluble sugar content. [ Conclusions ] The character of watermelon potassium absorption was that the least absorption in seedling period and the fastest potassium absorption rate in fruit expanding period. Therefore,the optimum management of potassium fertilizer was 90 kg-hm-2 K2O basic fertilizer and 180 kg. hm-2 K2O top fertilizer in fruit forming period. The rate of basic fertilizer to top fertilizer of potassium management was 1：2.

关 键 词：西瓜 钾素吸收 吸收速率 产量 品质 

分 类 号：Q945.12[生物学—植物学]