| Rice is the world's most important grain crops, more than 50 percent of the population one with rice.. The rice planting areas is particularly widespread, But its characters, output and quality are easily infected by environmental condition. Especially the temperature and water of the time in the milk is the biggest factor to decide its quality. According to the research the difference of paddy rice quality caused by seedtime adjustment, height above sea level, region characteristics, and so on. It has direct relation with which caused by the temperature and water change.The rice H5 sample grows rice seedlings with conventional method. Treating the experimental materials to the booting stage, then select the materials whose growth advancement and trend in the basic consistent situation. And moved into the earthen bowl, each has three, continue to raise for several days. In the day of rice growing to the consistent degree, transfers to climate box. Then take the sample (function leaf) every seven days. The refrig will freeze the preserved sample, after treating the rice mature, the unification will carry on the related test analysis.the research of photosynthetic characters and physiological indices were measured during grain-filling period with high temperature and drought stress. The experimental result is below.1 The flag leaf of different drought processing,photosynthetic rate(Pr), transpiration rate (Tr), stomatal conductance(Cs) and intercellular CO2 content was decreased tendencies under High temperatures. One important indicator of photosynthetic system is the photosynthetic., High-temperature flooded processing fell to 61.64%, high-temperature moderate drought processing fell to69.31%,high-temperature highly drought fell to76.36%. The impact of high temperatures and drought, physical activities all slow, but slow different degree, including highly drought in the most serious slowdown degree, followed by moderate drought, flood slow down the slowest degree.2 Under High temperatures and different drought, the flag leaf rice conductivity average increase. High-temperature flooded processing increased by 44.92%,high-temperature moderate drought processing increased by 86.63%,high-temperature highly drought increased by 96.48%,reflecting the high temperature and drought rice cell membrane permeability to a certain extent of the injury which is to increase the permeability of cell membranes under high temperature and drought stress.3 Membrane lipid peroxidation named MDA has a marked increase under High temperatures and different drought,, High-temperature flooded processing increased by30.09%,high-temperature moderate drought processing increased by42.28%.high-temperature highly drought increased by 53.85%.In the first seven days Three different drought in three processing period differences reached significant levels4 Under High temperatures and different drought, the flag leaf rice proline content all increase. High-temperature flooded processing increased by 44.92%,high-temperature moderate drought processing increased by 86.63%.high-temperature highly drought increased by 96.48. Adversity conditions the content of the more serious, proline content more5 Under High temperatures and different drought,.the SOD,POD and other antioxidant enzyme activity is all decreased significantly. The hydrogen peroxide, superoxide as the oxygen of the indicators of activity have increased significantly. Between the two types of indicators is a negative correlation. It indicated that under the high temperature and drought treatment rice leaves reactive oxygen species in the accumulation of reactive oxygen species due to removal of the main activity of the suppression of active oxygen content increased. That is high temperatures damaged the plants to maintain active oxygen production and remove the dynamic balance, so that timely removal of plants in the accumulation of reactive oxygen species decline.6 chlorophyll amount, chlorophyll a t, chlorophyll b content and Chl a/Chl b is decreased significantly under High temperatures and different drought,and The photosynthetic related index is down. The correlation analysis showed that chlorophyll content and membrane between photosynthetic was a certain correlation. The results indicated that Chlorophyll amount, chlorophyll-a,chlorophyll b and chlorophyll a/chlorophyll b values are decreased obviously, directly affecting photosynthesis.The results indicated that the plants infiltration of regulation is decreased, the antioxidant activity is also decreased. Through reducing the cell's ability to eliminate active oxygen, it caused hazards to the cells after the high temperature and drought treatment.
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