彭李顺 杨本鹏 曹峥英 曾军 冯信平 蔡文伟 张树珍 甘仪梅

摘 要 以国内当前甘蔗主栽品种ROC22为材料，通过田间实验分析了甘蔗主要器官钾素含量、累积、分配和吸收的动态变化特征。结果表明：在相同生育期，上部茎和青叶鞘始终是钾素含量较高的器官，青叶和中、下部茎次之，根系、枯叶和枯叶鞘则始终相对较低。钾素主要累积于青叶（鞘）和蔗茎中。拔节前青叶（鞘）中的钾素占植株总累积量的95%以上，拔节后其钾素分配比例持续下降，而蔗茎中则持续上升，在工艺成熟期分配至蔗茎的钾素占整个植株的83.3%。甘蔗钾素阶段吸收量和吸收速率则呈现了先上升后下降的趋势，分蘖期至茎伸长4期为甘蔗主要钾素吸收积累阶段，占生育期总吸收的86.8%，其中分蘖期至拔节期的钾素阶段吸收量（4 791.3 mg/plant）和吸收速率（159.7 mg/plant·d）最高，为甘蔗钾素吸收的最大效率期。

关键词 甘蔗；钾素；吸收；累积；分配

中图分类号 S556.1 文献标识码 A

Abstract The aim of this study is to investigate the dynamic characteristics of potassium（K）content， accumulation， distribution and absorption in sugarcane variety ROC22 during the whole growth period under K fertilization. The results showed that K content was always higher in the green leaf sheaths and upper canes， followed in the green leaves， middle and lower canes， and in bone-dry leaves， bone-dry leaf sheaths and roots which was lower in the same growth stages. K nutrient mainly accumulated in green leaves （sheaths） and canes. Before jointing stage， more than 95% of K was distributed into the green leaves （sheaths）. K distribution ratio of green leaves（sheaths）continually decreased， and that of canes kept elevating. In technical maturity stage， most of K was gathered in canes， reached 83.3% of the whole plant. K absorption in the whole plant exhibited an obvious trend of first increase and then fall， and K absorption amount from tiller stage to cane elongation 4 stage accounted for 86.8% of total absorption amount during the entire growing period. The most efficient period for K utilization was tiller to jointing stage in sugarcane， K absorption amount and ratio during this period reached the peak value， 4 791.3 mg/plant and 159.7 mg/plant·d respectively.

Key words Sugarcane；Potassium；Absorption；Accumulation；Distribution

doi 10.3969/j.issn.1000-2561.2016.10.004

甘蔗是最为重要的糖料作物，其产糖量约占中国食糖产量的92%以上[1]，蔗糖产量对保障中国食糖安全具有重大战略意义。甘蔗属于高光效的C4类作物，具有生长周期长、生物产量高和养分需求量大的特点，因此保持充足的养分供给是实现甘蔗高产的关键。在众多植物必需的营养元素中，甘蔗对钾素的需求量最高，属于喜钾作物[2]。钾素能够促进甘蔗的光合作用，增强体内物质合成和运转，提高能量代谢，且对糖分的运输积累以及逆境胁迫抗性等也均有积极作用[3-8]。……