Abstract: A three-stage agricultural product supply chain competition and game model including farmers and agricultural cooperatives is developed which is dominated by the enterprise. Three kinds of farmer capacity selection strategies are proposed based on the horizontal Cournot competition and vertical Stackelberg game equilibrium solution, and the competition space of the downstream members participating in the game and the capacity of the supply chain are discussed. The results show that the strategy of optimal cooperatives profit is superior to the strategy of optimal social welfare, and the strategy of optimal total profit of supply chain is better than the strategy of optimal cooperatives profit in a certain range. The competition space of the downstream members participating in the game has an upper bound and a lower bound. The structure of the agricultural supply chain comes to equilibrium and the supply chain comes to the largest capacity under the upper bound. The strategy of optimal cooperatives profit gives the enterprises more competition space and the optimal social welfare strategy gives the cooperatives more competition space.

Key words: agricultural product supply chain, farmers capacity selection, competition space, equilibrium structure