Availability of fertilizer recommendation based on yield response andagronomic efficiency of Chinese cabbage

Objectives The currently used fertilizer recommendation methods often need soil and plant analysis, uneasy to be extended in practical vegetable production. We attempted the fertilizer recommendation method based on yield response and agronomic efficiency, in order to verify the availability of the method.

Methods In the autumn of 2018, two cabbage field experiments were arranged in Weishanzhuang and Zhangziying towns, Daxing District, Beijing. In each experiment, farmers' practice fertilization (FP) was taken as control; optimized fertilization was setup based on yield response and agronomic efficiency (OPT); based on OPT, four other treatments were setup, including organic fertilizer replacing 30% of N (OPT+OM), N omission (OPT-N), P omission (OPT-P) and K omission (OPT-K). The yield, nutrient uptake, fertilizer utilization and net income of Chinese cabbage were investigated.

Results Compared with FP treatment, the yields of Chinese cabbage in OPT treatments in Weishanzhuang and Zhangziying were significantly increased by 13.3% and 18.0%, respectively; the uptake of N, P and K were significantly increased by 35.1, 24.1 and 165.1 kg/hm² in Weishanzhuang, and 92.7, 29.6 and 123.3 kg/hm² in Zhangziying, respectively. The yield of Chinese cabbage in OPT+OM treatment in Weishanzhuang was 9.8% higher than that in FP treatment, and slightly lower than that in OPT treatment; the yield in OPT+OM treatment in Zhangziying was significantly decreased by 22.3 t/hm², compared with that of OPT, and increased by 1.8% compared with that of FP treatment. The net income of OPT treatment was 12.7%–58.5% higher than those in FP and OPT+OM treatment in the two experimental sites. Compared with FP treatment, the partial productivity, recovery use efficiency and agronomic efficiency of N and P in OPT and OPT+OM treatments in the two sites were improved, while the agronomic efficiency of K in FP treatment was significantly higher than that in OPT and OPT+OM treatments due to the low potassium application rate. Except the significantly higher partial productivity of K in OPT+OM treatment in Zhangziying town, the N, P and K use efficiency indexes of OPT+OM treatment in the two experimental sites were equivalent to or significantly lower than those of OPT treatment.

Conclusions Both the experiments have proved the significant effect of the recommended fertilization based on yield response and agronomic efficiency in improving the yield, production benefit and fertilizer use efficiencies of Chinese cabbage. So we could conclude that the method is easy and available for fertilizer recommendation in different yield and field fertility levels, although further study still needed for the recommendation of the partially replacement of chemical nitrogen with organic fertilizers.