Response Of Rice To Climate Change And Adaptive Strategies In Shenyang Area

Currently,the global surface temperature rising,and climate events occrued frequently,the world was experiencing a warming as the main feature,which had an important impact on China's agricultural system and the natural environment.Rice was the most widely planted in China,and Northeast China was the highest of rice production area..Rice was very sensitive to temperature changes,the temperature too high or too low would cut the yield of rice.At present,the study of climate change on agricultural production mainly concentrated in 2 method:observation and model simulation.In our study,the impact of climate change on rice in Shenyang used two methods,experiment and the simulation model,and uesd the crop model to discuss the effective measures to adapt climate change,having a certain significance to ensure food safety and efficient production.the experiment was conducted in climate chamber to explore the effects of different intensities of low temperature on stomatal conductance of rice with different maturity at booting and blooming stages in Shenyang region,two temperature treatments were stetted for 5 days,which were 3?(D3)and 5?(D5)lower than outside temperature,CO2 and light response curves of second leaf from top were measured for treatment and control plants(grown under natural conditions as control,mark CK)by using LI-6400 photosynthesis analyzer.With using latest climate data of CMIP5 combined with CERES-Rice model,analysied the influence of future climate change on rice growth in Shenyang area,and explored measures adapt to climate change by changing the varieties,adjusting the sowing time,cultivation of new varieties,draw the following conclusions:(1)Effects of low temperature on stomatal conductance of rice at different maturity stages.during CO2 response,the leaf stomatal conductance of D3 and D5 treatment plants showed a significant decrease compared with that of CK plants for 9035(middle)and 9036(late)maturity varieties,while decrease for 9023(early)maturity variety only in D5 treatment.During light response,the leaf stomatal conductance of treatment plants showed a significant decrease compared with that of CK plants for 9035(middle)and 9036(late)varieties,but increase for 9023(early)maturity variety in D3 and D5 treatment(P<0.01).(2)Effects of low temperature on Photosynthesis of rice at different maturity stages.During CO2 response and light response,the leaf photosynthetic rate of D3 and D5 treatment plants showed a significant decrease compared with CK for 9035(middle)and 9036(late)maturity variety,but a slight effect on 9023 early maturity.Stomatal limitation mechanism is the main mechanism that leads to decrease of photosynthetic induced by low temperature for 9035(middle)variety.Whereas,the decline in photosynthetic rate are mainly due to non-stomatal limitation for 9023(early)and 9036(late)maturity varieties.(3)Adaptability of CERES-Rice in Shenyang area.The simulation ability of CERES-Rice model was verified by flowering stage,maturity stage,yield.The simulation results of the model were satisfactory,and the model was suitable for the simulation application in Shenyang area.(4)Effects of future climate change on growth and yield of rice.Growth period of rice was ahead during 2020-2050 and 2050-2080 two time periods in Shenyang,and for variation range of different maturity varieties,late>middle>early maturity.The trend of 2050-2080 was more obvious during the period 2020-2050.rice yield showed a decrease during 2020-2050 and 2050-2080 in two periods in Shenyang,and for variation range of different maturity variety,middle>early>late maturity.Compared with yield of 2020-2050 period,2050-2080 period's reducing reduced trend was more obvious.(5)Adaptive measures.Introduction from warmer areas or sowing early and late varieties,early sowing time,increasing the single grain weight G2 and potential grain number system G1,the high temperature coefficient G4 can effectively increase the yield of rice.