Abstract: Based on the theories, this paper expounds the logic mechanism of the impact of agricultural production services on grain yield and quantitatively estimates the impact of agricultural production services at different links on the grain yield per unit area by using the micro-survey data and the econometric method. Then it empirically tests the influencing mechanism. The results reveal that, firstly, fertilization service and agricultural machinery service can significantly increase the grain yield per unit area, and that the fertilization service mainly with technological substitution has a greater effect on grain yield per unit area. Fertilization service and pesticide service have significant promotive effect on the grain yield per unit area of large-scale operation farmers. Secondly, the fertilization and pesticide services can significantly promote farmers to adopt pro-environment fertilization technology and pest control technology. Thirdly, agricultural machinery service, fertilization service and pesticide service have obvious substitution effect on agricultural labor input, and can significantly promote the farmers with large-scale business to transfer farmland into their operation, but no evidence is found to prove that the agricultural machinery service and the fertilization service have significant influence on the farmland transfer of small farmers. The above conclusions imply that, in the future, China should vigorously promote the development of agricultural production service organizations, strengthen the policy support for the fertilization and pesticide links with lower standardization degree and higher probability of moral hazard, reduce the cost of service operation, and give better play to its role in promoting grain yield and farmers' adoption of the pro-environment agricultural technologies.

Key words: agricultural production services, the per unit area yield of grain, substitution effect, new agricultural technology, land transfer.