| Price fluctuation and quality safety of vegetables is a growing problem in China. In this dissertation, I develop historical, qualitative and quantitative distinctions between four typical supply chains of vegetable by tracing back to how power of discourse was formed, changed, and what effects it brought to excavate the social roots which caused price fluctuation and quality safety problems. I argue that the vegetable supply chain is actually a chain of power transmission in which power of discourse was formed when discourse was used by subjects of discourse to impress, control and dominate objects of discourse. Moreover, resistance of objects drove the transmission and changing of power of power, while government and social media promoted the historical change of power of discourse in the supply chain.It is proved in the study that distribution of power of discourse was adjusted continuously to shorten supply chain, reduce operating cost and stabilize price and supply of vegetable when vegetable supply chain changed from ’wholesale market as the core’,’leading enterprises as the core’ to’farming-supermarket docking’. However, in essence, distribution of power of discourse wasn’t changed at root if through an integral view, because power of discourse was still controlled by wholesalers, leading enterprises and supermarkets that held power of price negotiation and gained maximized benefits in their cooperation. Power of discourse on quality safety was also ’kidnapped’by their interest to be "vacuous", that is, no efficiency or low efficiency. Vegetable farmers and consumers were all excluded from benefit group and their power of discourse and power of price negotiation were missing.’Those who grow vegetable cant make money’ and ’those who buy vegetable cant save money’ described the situation of distribution of power of discourse. They are oppressed to take the risk and loss in market, or use low price agricultural capital as ’weapons of the weak’, which causes’bad money drives out good’. In ’farming-consumer docking’ model, farmers, consumers and cooperatives could gain equal power of discourse and price negotiation. Nevertheless, it can’t become the main model of popular vegetable supply chain yet. Therefore, structure optimization of vegetable supply chain itself can’t automatically break the puzzle where price fluctuation and quality safety frequently occurred. Beside, inadequate government initiatives on stabilizing price brought farmers benefit lost on the contrary.At last, this paper argued four hot issues in vegetable supply, including:vegetable market competitive situation has been formed, but market only got malfunction in farmer’s and consumer’s discourse power; present vegetable supply policy breeded entities with monopoly power in the vegetable market who controlled discourse power; vegetable quality and safety issues simply attributed to farmers, depriving of farmer’s discourse power and the government was not the single deparment to manage and guarantee vegetable quality and safety. |