Relationships Between The Physiological And Biochemical Indexes And The Yield Characteristics Of Rice Under High Temperature Stress

The high temperature produces some effects on the normal physiological andmetabolic processes of the rice in different stages. However, at present there are fewrelevant reports about the effects in different periods of high temperature stress on ricedevelopment treatments on the seed setting rate and grain weight and the relationshipbetween the physiological and biochemical indexes on the yield characteristics of riceunder the high temperature stress in different developing stages. This article utilizedartificial greenhouse to offer high temperature stress to treat the high-temperatureresistance variety and high temperature sensitive variety at booting, heading andflowering stage and grain-filling and seed setting stages, and then contrast with thosegrew in the field which after high temperature treatment, taking down the two leavesin the last, what’s more, research on the corresponding relations of some physiologicalindices in rice leaves and yield traits designed to identify the best periods forresearching the high-temperature resistance variety and high temperature sensitivevariety.What’s more, manage rice with high temperature stress ladderlike time in theheading and flowering stage, and the main results are:1. The results of different time of high temperature stress in the heading andflowering stage showed that the content of Chlorophyll declined quickly on the thirdand forth day in the high temperature stress stage. With the extend of stress time, thecontent of Chlorophyll of fastness variety came back in some degree. But that of hotsensitive variety was last decreasing, and the content of Chlorophyll of thehigh-temperature resistance variety is higher than the high-temperature sensitivevariety all the time. In the progress of high temperature stress, the content of solublesugar in rice leaves decreased obviously especially in the third and forth day of thisstage, and with the extend of the time of high temperature stress; the content ofsoluble sugar was relatively steady.In the whole high temperature stress progress, thecontent of soluble sugar of the high-temperature resistance variety Lvyou1is morethan middle state variety Fengliangyou1and Tianxie1all the time. Content ofEndogenous polyamines of the high-temperature resistance variety Lvyou1is morethan Fengliangyou1and Tianxie1. Content of endogenous polyamine of thehigh-temperature sensitive variety Tianxie1was the lowest. Among these three polyamines which are put, spd and spm, the content of spd was the highest, and thecontent of spm was the lowest.2. Results of high temperature stress in different bearing era showed that therehappened high temperature stress in grain-filling and seed setting stage, and comparedto the booting stage and the heading and flowering stage, the differences on theChlorophyll content of the high-temperature resistance variety and thehigh-temperature sensitive variety were especially prominent. The high-temperatureresistance variety still maintain the higher level of the increase of soluble sugarcontent than the high-temperature sensitive variety.(when the increase of solublesugar content of the high-temperature resistance variety is64%, the increase ofsoluble sugar content of the high-temperature sensitive variety is32%). The increaseof soluble protein content of the high-temperature resistance variety is significant.(Which has increased41%).while it is reduced greatly of the high temperaturesensitive variety (Which has reduced16%).3. After high temperature stress, compared to the booting stage and the headingand flowering stage, the differences on the seed setting rate and seed weigh wereespecially prominent between the high-temperature resistance variety and thehigh-temperature sensitive variety on the grain-filling and seed setting stage, thehigh-temperature resistance variety still maintain the high level of seed setting rateand seed weigh, and the seed setting rate and seed weigh of the high temperaturesensitive variety are reduced greatly.And the same trend as changing of Physiologicaland biochemical indexes. The high temperature stress occurring on the grain-fillingand seed setting stages could distinguish the high-temperature resistance variety andhigh temperature sensitive variety, so the grain-filling and seed setting stages areprobably the best periods to research the high-temperature resistance variety and hightemperature sensitive variety.