Excessive application of fertilizer not only cause low utilization ratio of fertilizer, brings the land surface source pollution, have failed to solve the problem elements missing crop. Balanced fertilization, micro elements fertilizer added, so as to improve the overall nutrient utilization rate has been imminent. This is the reporter held in Beijing last week at IFA (China) to obtain information on the chemical fertilizer sustainable development forum.

At present, trace elements in cultivated soils in China lack of very serious. The International Zinc Association expert Fan Mingxian pointed out, plant growth has 16 essential nutrients, except carbon, hydrogen, oxygen, a lot of other elements and trace elements must be extracted from the minerals. If there is a shortage of nutrients, so even if the other nutrient supply more, the crop yield by the lowest nutrient limitation is difficult to improve. This is the economics in the famous short board effect.

The experts said, in the balanced fertilization process, must consider the use of trace elements. Based on the application of nitrogen, phosphorus, potassium fertilizer, trace element supplement crop needs, so as to greatly improve the utilization ratio of fertilizer. In strengthening the nutrient management, we should consider not only the amount and time of application, but also to improve the rules of other nutrient elements.

The International Fertilizer Association (IFA) said the Secretary General Sherlock, nutrient management is in the correct proportions, at the right time, the right place with the right food resources (4R). According to the characteristics of soil and crop, balance fertilization, this is one of the important means to improve the utilization rate of fertilizer.

Director, Professor Ho Ping International Plant Nutrition Research Institute of China project of agricultural resources and regional planning Chinese Academy of Agricultural Sciences study further explained, the traditional nutrient management method based on soil testing and destructive soil environment, for China the complicated and changeable, the lack of flexibility. Based on the principle of expert system for crop nutrient nutrient management using 4R, can be carried out in accordance with the crop fertilization required, make full use of soil nutrient supply, including higher residual nutrient irrigation and rain brought nutrients, but also to maintain the balance of soil nutrients in addition to nitrogen, phosphorus, potassium, and also includes other trace elements and trace elements in, can greatly enhance the utilization rate of fertilizer.

In China the implementation of soil testing for 30 years, will continue to play an important role in nutrient management. Deputy director of Hubei Provincial Department of agriculture Xu Nenghai pointed out, now the soil testing and 30 years ago is not exactly the same, except for soil fertility and soil test detection, but also improved soil fertility, soil acidification problem solving. The future of formula fertilization by soil testing should also establish a complete technical system, the law of crop demand, supply capacity of soil nutrient combined in determining fertilization scheme.

However, director, International Food Policy Research Institute China project senior researcher Chen Zhigang said, there are still many problems to be solved, such as nutrient management in specific time and place, catch crops grown, although have the potential, but the high price; the majority of proposed method high nutrient use efficiency is still in the experimental or design stage, should be feasible technical support; fertilizer and fuel growing price to farmers to afford fertilizer.