Effect of Optimal Fertilization on the Growth and Fertilizer Utilization of Lactuca sativa in Shenzhen

Objective 2020 is the final year of zero growth in the use of chemical fertilizers. In order to consolidate the results of zero growth in chemical fertilizer use and verify the overall goal of more than 40% fertilizer utilization, an experiment on reducing fertilizer use and increasing efficiency was carried out combined with work tasks of our Center.Method Taking Lacfwca sa/zVa as tested crop, the experiment set up 6 treatments: no fertilizer, no nitrogen, no potassium, no phosphorus, formula fertilizer and conventional fertilization, to study the effects of different fertilization treatments on biomass of L. sativa, fertilizer contribution rate, fertilizer utilization rate and fertilization effectiveness based on soil testing and fertilizer recommendation technology.Result Fertilization could significantly increase the yield of L. sativa, and the yield increase ranges of different fertilization treatments varied from 81.89% to 410.63%. The variation ranges of fertilizer contribution rates of different fertilization treatments varied from 40.71% to 79.91%, and the variation ranges of agronomic utilization rates varied from 54.57 to 120.41 kg/kg. The utilization rates of N, P, and K of formula fertilizer treatment were 43.52%, 22.27% and 57.54%, respectively, while those of conventional fertilization treament were 39.04%, 7.47% and 51.85%. From the perspective of economic benefits, the incomes of different fertilization treatments were showed as: formula fertilizer > no phosphorus > conventional fertilization > no potassium > no nitrogen.

Conclusion Under the premise of ensuring crop yield, reducing the fertilizer application amount can increase the utilization rate of fertilizer and increase farmers' income by optimizing the application of fertilizer through soil testing and fertilizer recommendation technology.