Effects of different potassium levels on nutrient absorption and utilization of N , P , K in sugarcane

Two sugarcane varieties were grown under hydroponic culture at different levels of potassium to evaluate their absorption and utilization of nitrogen, phosphorus and potassium. The result showed that with the increase in K level, the dry weight increased significantly, but the root/shoot ratio reduced. The root weight and root / shoot ratio of BC2-32 was higher than YT55 but the shoot dry weight was lower at different K levels. The growth rate of dry weight in BC2 -32 was high than YT55 with the increase of K concentration.. High K levels could promote the N, P content in different organs and total accumulation amount of N, P in sugarcane. The utilization efficiency of N, P was significantly increased with the raising of K level. The ratio of N, P accumulation amount between shoot and plant and N utilization efficiency of BC2-32 were lower than YT55 at different K levels. The P utilization efficiency of BC2-32 was lower than that of YT55 under the low K treatment, but was opposite under the high K treatment. With the increase of K level, the plant K accumulation amount was increased significantly, whereas the utilization efficiency of K was reduced. The utilization efficiency of K in BC2-32 was higher than YT55 at different K levels.