Abstract: Taking 19 regions of 7 provinces and municipalities in the middle and lower reaches of Yangtze River as the objects, this paper analyzed the temporal and spatial distribution patterns of their daily maximal temperature over 35 ℃ from the 15th day before rice booting to the 20th day after rice flowering in last 36 years (1970-2005). According to the climate transient scenarios of these regions in 2030 and 2050 generated by GISS GCM Transient B Runs, the temporal and spatial evolving tendency of the daily maximal temperature over 35℃ was further discussed. In last 36 years, the day number of high temperature at the booting and flowering stages of early rice in the middle and lower reaches of Yangtze River increased significantly, and under the future climate scenarios, the day number of high temperature would be the largest for single-cropping rice, followed by for early rice and late rice. For double-cropping rice production areas, the day number of high temperature in the middle reaches would be larger than that in the lower reaches of Yangtze River. The relationships between the regional quantity of rice climate yield and the stress-index occurrence pattern in the same regions suggested that the rice-spikelet abortion due to high temperature was the main cause for the decrease of rice yield. In the two climate transient scenarios in 2030 and 2050, the yield decrement in the middle reaches of Yangtze River would be larger than that in the lower reaches, and the largest yield decrement would be the late rice in the middle reaches of Yangtze River.

Key words: Soybean, Ultraviolet-B(UV-B), Cadmium(Cd), SOD, POD, Indole-3-acetic acid(IAA)oxidase