Nutrients uptake and removal characteristics by high-yielding sugarcane grown in Guangxi, China

摘要

Fertilization starts from the information of nutrition uptake, but the uptake character of high-yielding sugarcane is still not clear. The objective of our research was to define the nutrition uptake and removal of high-yielding sugarcane. Thirty-one fields of sugarcane (ROC 22) with cane yield 50 above of average were selected from main producing area in Guangxi, south-west of China, to determine the n, P, k, Ca, Mg, s, b, Zn, Fe, Mn and Cu concentration in dry leaves, green tops, cane and stubble after harvest. The uptake amounts of nutrient above per unit plant parts were also computed. The results showed that 60 and 18.2-27.8 of the total uptake n, P and k accumulated mainly in cane and green tops, respectively. Ca, Mg, s, Mn and b accumulated mainly in cane. More than 50 of the total uptake Cu and Zn were in cane. Fe accumulated mainly both in stubble and cane, where each accounted for approximate 40 of the total uptake. The mean nutrient uptakes per tonne sugarcane produced were : n 1.81 kg, P_20_5 0.36 kg, k_20 2.11 kg, CaO 0.91 kg, MgO 0.42 kg, s 0.50 kg, Fe 37.5 g, Mn 15.5 g, Zn 6.2 g, Cu 2.2 g and b 0.74 g. The uptake ratio of n : P_2O_5: k_20 was 1: 0.20 : 1.16. Mean nutrient removal per tonne sugarcane was : ni. 67 kg, P_20_5 0.32 kg, k_20 1.85 kg, CaO 0.58 kg, MgO 0.32 kg, s 0.47 kg, Fe 19.2 g, Mnii. 3 g, Zn 5.0 g, Cu 1.8 g and b 0.51 g.