*3.1. Problem Description*

A two-level agricultural supply chain consisting of a risk-neutral agri-foods producer and a risk-neutral agri-foods seller is studied in this paper. Prior to the marketing season, the seller orders *q* quantities of common produce from the produce producer at a price of *p*0. However, considering that market demand is influenced by both the quality level and retail price of agricultural produce, and more and more consumers prefer green and organic agrifoods, the "Agricultural Produce Quality and Safety Enhancement Initiative" is proposed for the agricultural supply chain. This initiative aims at encouraging agricultural producers to increase quality inputs to improve the quality of agri-foods. Thus, the agricultural produce is as follows:

(1) In order to respond to the quality and safety enhancement initiative, the agricultural producer needs to increase the quality inputs, such as upgrading production technology level, improving production managemen<sup>t</sup> methods, etc. Referring to the study of Jiang [30], the research and development inputs for producing green products have a quadratic relationship with the greenness of the products. Therefore, it is assumed that the relationship between quality inputs *u* and quality safety degree *g* in agricultural production is *u* = 1 2*zg*<sup>2</sup>*,* where *z* is the production influence factor.

