Nitrogen,Phosphor and Potassium Fertilization Index for Kale Cabbage in Fujian

Based on the results of 59 field experiments of kale cabbage response to N,P and K fertilization in recent years,NPK fertilization indices for head cabbage in Fujian Province were developed.The results showed that there were linear positive correlation between the yield applying balanced fertilization and the yield in blank.The average contribution rate of soil nutrients to yield of head cabbage was 51.0%,the average increased yield of N,P and K applications was 40.4%,11.6% and 15.0% respectively.The critical indices of alkali-hydrolyzable nitrogen,Olsen-P and available K for high yield of head cabbage was 207 mg/kg,71 mg/kg and 157 mg/kg respectively.In general,the economic application rates was N 238 kg/hm2,P2O5 70 kg/hm2 and K2O 192 kg/hm2,and their proportion was 1 ∶ 0.29 ∶ 0.81.Relationship between soil testing value and their fertilization recommendation met with exponent regression equation.The model may be used for fertilization recommendation according to soil testing value and played the role of different application rate in different soil fertility levels.