Nutrient Management and Balanced Fertilization on Major Crops in Jilin Province

This long-term fixed field experiment has been conducted in Liufangzi County of Jilin Province since 1993. In this experiment, N and P₂O₅ rates were consistently applied at 225 kg/ha and 113 kg/ha, respectively, while K₂O rate was varied between 0, 113, and 225 kg/ha.

Results showed that 113 kg K₂O/ha increased yield by 1,637 kg/ha, or 17% above the 0 K check. Net income reached USD 307/ha at the intermediate K rate. When K was applied at 225 kg/ha, yield (net income) were only increased by 1,060 kg/ha (USD 91/ha) over the 0 K check. From 1993 to 1994, K application did not have a significant effect on maize yields, but from 1995 to 2010, K fertilizer had a significant impact on crop productivity. The absolute yield of maize increased between 538 to 2,223 kg/ha. Among the 16 years under study, the 113 kg/ha rate proved superior to 225 kg/ha in five years and there was no difference between the two rates in 10 out of 16 years. Thus, in only one year (2000) did the 225 kg/ha rate out-perform the 113 kg/ha rate. While not evaluated in this study, lower K rates may have met the crop K requirements at an even higher economic benefit. Jilin-NMBF