Studies and Demonstration on Environmentally Sound Fertilization Technology for Vegetables and Banana

Vegetables and banana are major crops in Fujian Province, and these crops need much more fertilizer than grain crops. Therefore, these two crops have a great impact on local fertilization efficiency, economics and the environment. To increase banana and vegetables yields and fertilization efficiency, the Soil and Fertilizer Institute of Fujian Academy of Agricultural Science carried out 11 field fertilization trials for banana and vegetables in nine counties, including a long-term site-specific field experiment with vegetable-rice rotation in 2013. Six treatments were used in the experiment, viz., OPT (optimum fertilization), OPT-N, OPT-P, OPT-K, FP (farmer practice) and CK (no fertilization). The N, P and K fertilizer application rates for different vegetable species and banana varied greatly.

Results showed that average nitrate-N concentration in the top soil layer of the vegetable fields was 47 mg/kg and the Olsen-P concentration was 62 mg/kg. The optimum N-P₂O₅-K₂O application rates were determined as 180-90-135 kg/ha for cucumber (yield 53.3 t/ha) and 315-180-180 kg/ha for courgette (zucchini; yield 44.7 t/ha) with significant economic benefit over FP. Double Speed Turning Point model were used to estimate N and P leaching potential in the vegetable soils. According to the 121 leaf sample analysis, the recommend nutrient diagnosis indices of banana leaf for local diagnoses were 3.15 to 3.30% for N, 0.23 to 0.35% for P, 3.85 to 4.0% for K, 0.5 to 1.2% for Ca, 0.28 to 0.40% for Mg, 0.23 to 0.27% for S, and 10.0 to 21.0 mg/kg for B. The optimum rate of N-P₂O₅-K₂O fertilization was 675-90-1,050 for banana for a yield 59.7 t/ha. This optimum rate increased banana yield by 7 to 14% and net income by 6 to 14% over FP.