锌和钾对甜菜生长中后期干物质积累的影响

Effect of Zinc and Potassium on Dry Matter Accumulation of Sugarbeet in Mid-Later GrowingSeason

单独施用锌肥和钾肥对提高甜菜生长中后期块根干物质积累的作用差异不明显，其效果低于这两种肥料共同施用。单独施锌有利于提高群体的叶面积指数，并具有延缓叶片衰老的功效，对提高块根含糖作用也较明显。单独施钾时，可以使生长中心转移提前。当两种肥料一同施用时，增加钾肥用量即可提高块根干物质，又可提高块根含糖量，而增加锌的用量效果不明显。

The effect of applying Single Zn and K_2O on increasing dry matter accumulation ofsugarbeet in mid-later growing periods were studied and the difference weren′t significant.The effect of mixing Zn and K_2O were better than single Zn or K_2O.Applying single K_2Owas good for increasing leaf area index of it′s population and sugar content of the root,andpostponing leaf′s senescence phase.When single K_2O was fertilized,the centre of beet′s growthwas put forward.When Zn and K_2O were mixed and applied,the dry matter and sugar con-tent of the root were raised as increasing amount of potassium,but the effectiveness was notsingnificant with increasing amount of Zinc.