甜玉米钾素积累和分配的基因型差异

Genotypic Differences of Potassium Accumulation and Distribution in Sweet Maize Varieties

为挖掘甜玉米品种潜力,在同一肥力水平和栽培条件下研究了22个甜玉米品种钾素积累和分配的基因型差异。结果表明：不同生长阶段钾素积累量品种间有显著差异,出苗–拔节期、拔节–开花期、开花–鲜食期的积累量分别占总积累量的10.0%、73.6%和16.4%,变幅分别为5.6%-19.8%、48.0%-88.8%、0.9%-42.1%。拔节期钾素主要分配在叶片和叶鞘中,拔节后分配到茎杆中的钾比例开始升高,到开花期钾素分配到茎秆中的比例达到峰值,其分配量占钾素总积累量的39.9%左右,后期保持平衡。在鲜食期,茎秆中钾素含量比例为39.5%,叶片为22.0%,籽粒为10.4%。回归分析表明：高产（鲜果穗和鲜籽粒）品种其拔节至开花期具有较高的钾素积累量,且鲜食期苞叶中钾素分配率较低。在供试22个品种中,金师王等7个品种的鲜果穗和鲜籽粒产量、钾素积累量、鲜食期籽粒中钾素分配比例较高,综合表现较优。

In order to improve the genetic potentiality of potassium（K） uptake and utilization in sweet maize varieties, the genotypic differences of K accumulation and distribution of 22 sweet maize varieties were studied under same climate and soil with same fertilizer level. The results showed that K accumulation at different stages were different among different varieties. The mean of K accumulation percentage at the seedling-jointing stage, jointing-silking stage and silking-fresh stage was 10.0%, 73.6%, 16.4%, and with the range of 5.6%–19.8%, 48.0%–88.8%, 0.9%–42.1%, respectively. At the jointing stage, K was mainly in the leaf and sheath. After the jointing stage, the percentage of K in stem increased and reached maximum at the silking stage, viz. 39.9%, and kept stable in the following stage. At the fresh stage, the percentages of K in the stem, leaf and kernel were 39.5%, 22.0% and 10.4%, respectively. The varieties that had high fresh ear and grain yield had higher K accumulation amount at the jointing-silking stage and lower K distribution percentage in bract at the fresh stage. Among the 22 test varieties, 7 varieties（JSW etc.） had higher fresh ear and grain yield, higher K accumulation amount and higher distribution percentage in the grain at the fresh stage than those in the other 15 varieties.