马铃薯需钾特性及钾肥效应

THE CHARACTERISTICS OF POTASSIUM REQUIREMENTAND THE EFFECT OF POTASH IN POTATO

试验结果表明，钾对马铃薯营养生长有明显促进作用。团棵期施钾处理株高较对照平均增加３．２ｃｍ，鲜重增加１１．６ｇ；盛花期分别增加２．４ｃｍ和４９．１ｇ。植株含钾量随着植株生物量的增大而减小，前期植株中钾的含量３．８５％～４．６２％，后期钾的含量为１．６３％～４．１９％。植株吸钾量则随着生物量的增大而增加，前期０．６～０．８ｇ／盆，后期４．１２～５．８６ｇ／盆。施钾处理较对照平均增产６．８％，不施钾土壤速效钾和缓效钾均有下降，分别降低２７．７和５３．０ｍｇ／ｋｇ。

The result showed that potash had a significant effect on the vegetative growth of potato.In the early stage,the average plant height for the potash treatments was 32cm higher than that of control,and the fresh weight was increased by 116g over that of control.In the flower stage,the two indexes increased by 24cm and 491g,respectively.As the biomass increased,the total K content in the plant decreased.In the early stage, total K content in the plant was 385462%, whereas in the late stage, it was in the range of 163419%.The amount of potassium uptake by plant was increased as the biomass increased during the growth stages.In the early stage,it was 0608g/pot,while in the late stage,it was 412586g/pot.With potash application,the average yield increased by 68%.Without potash application,the available K and slowly released K content in the soil decreased by 277 and 530mg/kg,respectively.