The effect of plant growth regulator 6-BA and GA, which were sprayed during the filling stage of rice on senescence in the later stage was studied.The results showed that 6-BA and GA can slow down the falling of the chlorophyll and protein in the flag leaves, restrain the decrease of the POD activity and the accumulation of MDA.To a certain extend, 6-BA and GA can retard the senescence of functional leaves, which benefit the filling of rice, and improve the yield and quality. Key words:
The effects of temperature and light on the content of soluble protein and soluble sugar in rice leaves and grains were discussed. High temperature promotes the translocation of soluble protein and soluble sugar from leaves to grains, resulting in the high content of them in grains, and at the same time, it accelerates the senescence of leaves, resulting in a high remains of them in leaves and low grain-weight. At identical high temperature, the senescence of leaves in weak light is slower than that in strong light. Moderate temperature makes the translocation of soluble protein and soluble sugar from leaves to grains steady and transduction of sugar to starch to a greater degree, resulting in full grain filling. At the same low temperature, the strong photosynthesis in strong light can make up for the fast senescence. Among the four combinations, low-temperature and strong-light are most advantageous to milk filling, and the high-temperature and weak-light are the worst.