不同钾镁施用水平下甘蔗花叶病对甘蔗产量的影响

在甘蔗伸长盛期,SCMV—A侵染的蔗株叶片中蔗糖含量明显低于健株,还原糖含量则相反;不同钾、镁肥施用水平下,SCMV—A侵染的蔗株均比对照健株显著矮化,蔗茎和蔗糖含量均显著降低.而蔗茎锤度、蔗糖和还原糖含量则因钾、镁肥施用量的不同或高或低于其相应健株;适量施钾可增加健株的蔗茎及蔗糖产量,又可部分减少由SCMV—A年致的产量损失.施镁肥也有部分减少由SCMV—A引致产量损失的效果.

Influence of Sugarcane Mosaic on Yields of Sugarcane under Various Potassium and Magnesium Levels

The contents of sucrose in the leaves of the SCMV-A-infected sugarcane plants in the fastest growing season were lower than those of the healthy ones, whereas the contents of reducing sugars were contrary. The infection of SCMV-A significantly stunted the growth of sugarcane plants and decreased the yields of cane and sucrose in various potassium and magnesium levels. The brixs and the contents of sucrose and reducing sugars in the diseased plants were either higher or lower than those in the healthy ones and varied with potassium and magnesium levels. An appropriate supply of potassium fertilizer increased the yields of cane and sugar of the healthy plants and decreased the losses of cane and sugar by SCMV-A as well. The effect of magnesium supply on decreasing the losses of cane and sugar was also found. A way to decrease the losses of cane and sugar by SCMV-A by increasing potassium and magnesium fertilizer supply properly in the lower K~+ and Mg~(++) levels of sugarcane soils etc. was concluded and also discussed.