钠替代部分钾对棉花生长和养分吸收的影响

The effects of partial replacement of potassium by sodium on cotton growth and nutrition absorption

钠替代部分钾的盆栽试验结果表明，在供试土壤速效钾和水溶性钠偏低的条件下，钠可以替代部分钾的作用。当Na施用浓度低于500mg／kg时，对棉花苗期的生长有明显的促进作用；施Na1000mg,／kg，棉种出苗率仅为60％，病苗死苗率达80％以上，生物量显著降低，可认为是Na对棉花苗期生长的临界值。将土壤速效钾水平调到K20120mg／kg、土壤水溶性钠水平调到Na80mg／kg，K20与Na之比为1：0．67时，棉花苗期、蕾期和花铃期单株干物质积累量和钾、钠吸收量明显增加，可获得最好的籽棉产量，增产8．96％～10．28％。

By this pot experiment, the Na was lower than 500 mg/kg, the cotton growth was promoted obviously. When Na level was 1000 mg/kg, the seeding rate of cotton was only 60%, the sickness seedling rate reaches above 80%. And the biomass remarkably reduced. That is the marginal value of employment Na in cotton seedling stage. Under the condition of the low water-soluble K strength in the test soil, when K level is 120 mg/kg, and the supply of Na level is 80 mg/kg, and the ratio of K20 to Na is 1：0.67, accumulation of single sapling dry matter for the period of cotton seedling, bud and fllower-boll were increased remarkably. And the absorption of Na and K are the same. The production increased 8.96% to 10.28 %. And the unginned cotton reached the most production.