Effect Of Simulated Temperature Increase On Soybean Growth In Saline-Alkali Land Of The Yellow River Irrigation Area In Ningxia

The "Statement of the Global Climate in 2019" pointed out that as of the end of 2019,the global average temperature has risen by 1.1 degrees Celsius than before industrialization.A series of ecological problems caused by climate changc have caused widespread concern in the community.Due to climate warming,The impact of global climate change on all human beings,and the impact of climate warming on agricultural production has become a hot spot for scholars at home and abroad.In order to study the impact of climate change on the growth and development of soybean(Glycine max)in Ningxia Yellow River Irrigation Area,to explore the relationship between the growth and development,nutrient absorption and utilization of soybeans in saline-alkali land under climate warming,and the improvement of saline-alkali land in Ningxia University in Pingluo County in 2019 In the experimental station,using the method of open infrared temperature increase test,the effect of simulated temperature increase on the growth and development of soybeans in saline-alkali land in the Yellow River Irrigation Area of Ningxia was studied,and the effects of large temperature rise of 0.5℃,1.0℃,1.5℃ and 2.0℃ on soybeans were discussed.Growth period and its influence on morphology,physiology,nutrient utilization and grain quality in each development period,the results show that:1.Increased temperature is beneficial to the growth and development of soybeans.Increasing the temperature by 0.5～2.0℃ shortened the development days of soybean during the whole growth period by 4 days,12 days,21 days,and 24 days,respectively.During the whole growth period,the dry matter accumulation rate increased by 4.96%to 7.27%,10.49%to 15.99%,13.21%to 20.27%,and 17.32%to 36.17%respectively;the plant height increased by 0 to 11.31%,4.82%to 29.84,respectively.%,7.06%～46.00%,7.38%～57.71%.Prior to the pod setting period,the order of the average root-to-root ratio of soybeans under various temperature-increasing treatments is:+2.0℃>+1.5℃>＋1.0℃>+0.5℃>+0℃.During the flowering period,the soybeans increase with the increase of temperature gradient Compared with CK,the leaf length increased by 4.32%,9.62%,1 1.85%,and 17.37%(P<0.05),respectively,and the leaf area increased by 9.62%,24.12%,41.54%,and 47.34%,respectively.2.Increasing the temperature is beneficial to improve the stress resistance and photosynthetic ability of soybean leaves.Increasing the temperature by 0.5～2.0℃increased the activities of antioxidant protective enzymes such as SOD,POD,CAT and soluble sugar,soluble protein content(P<0.05),and decreased the contents of MDA and Pro(P<0.05).With the increase of temperature increase,the SPAD value,net photosynthetic rate,daily photosynthetic rate,transpiration rate(Tr),water use efficiency(WUE),stomatal conductance(Gs)and intercellular CO2 concentration(Ci)of soybean leaves,Photosynthesis parameters such as light saturation point and light compensation point increase,photosynthetic capacity,dark respiration rate and water use efficiency all increase.The synergistic effect of temperature and CO2 concentration on soybean photosynthetic capacity and water use efficiency have shown a promoting effect;temperature increase will enhance the use of soybean low-concentration CO2,but the use of high-concentration CO2 utilization capacity will be reduced,and narrow the CO2 utilization.3.Temperature increase is conducive to the increase of N,P,K content and accumulation of different organs and plants of soybean at various growth stages.Soybean plant pairs of different growth stages had the most accumulated K,followed by N,and the least P.In the vegetative growth stage,as the temperature increasing gradient increases,the greater the proportion of NPK distribution in the leaves,the smaller the distribution ratio in the root system.In the reproductive growth stage,as the temperature increasing gradient increases,NPK distribution in the pods The smaller the proportion,the greater the proportion allocated to the root system and stems,resulting in a decrease in NPK fertilizer utilization efficiency.4.Increasing the temperature is conducive to increasing the 100-grain weight of soybeans,but it reduces the number of effective pods per plant and the yield.The 100-grain weight increased by 1.3%,4.4%,4.7%,and 8.4%compared with CK under each temperature-increasing treatment(P<0.05),but the number of effective pods of soybean decreased significantly under the temperature-increasing treatment.32,the number of soybean effective pods decreased by 2,4,6,and 7 compared with CK under the treatment of temperature increase of 0.5～2.0℃,and the final yield decreased by 6.59%,8.40%,15.82%,and 13.82%(P<0.05).As a result,the harvest index decreases with increasing temperature gradient.5.The content of saturated fatty acids in soybean grains increases with the increase of the temperature increasing gradient.The unsaturated fatty acid content responds differently to the temperature.The protein and fat content under the temperature increasing treatment increases by 4.42～7.75 compared with CK with the increase of the temperature increasing gradient.%,2.00～5.74%(P<0.05),the effect of different temperature increasing gradients on soybean quality traits ranks as CK>+1.5℃>+1.0℃>+0.5℃>+2.0℃.