[Objective]The effects of high temperature stress on pepper yields were studied to provide a reference for pepper variety breeding and high-yield cultivation.[Method]Through outdoor long season cultivation,yields of different pepper cultivars in each temperature stage during the whole period were studied.[Result]The most appropriate time for pepper growth in the middle and lower reaches of the Yangtze River was short( Jun. 16- Jul. 15,Aug. 16- Sep. 15),the range of temperature was from 20. 70 ℃ to 30. 74 ℃....