Effects Of Different Altitudes On Physiological Characteristics And Yield Of Flag Leaves Of Highland Barley Varieties(lines) In Nyingchi City,Xizang Province

In this study,15 winter(spring)highland barley was selected as the research material,and 3 sites were set respectively in the altitude range of 2177 ～ 3386 m in Nyingchi City,Xizang Province.Traditional variance analysis and membership function analysis were used to explore the effects of different altitudes on physiological characteristics and yield characters of different flag leaves of highland barley,and to reveal the physiological mechanism of response of plateau highland barley to different altitude regions in Nyingchi City.It provides reference for the layout of highland barley varieties in different elevations of Nyingchi City.The following conclusions are drawn:(1)Photosynthetic characteristics of flag leaves showed that the photosynthetic rate of flag leaves of 8 spring sowing varieties was the highest in Duoji Township(3386m),while stomatal conductance,intercellular CO2 concentration and transpiration rate were the highest in Huiduo Township(2748m).The photosynthetic characteristics of flag leaves of spring sowing varieties with different ripening types were different in response to altitude.The photosynthetic characteristics of mid-ripening varieties in Huiduo Township(2748m)were the best,those of early-middle ripening varieties in Bayi District(2982m)were the best,and those of early-ripening varieties in Duoji Township(3386m)were the best.Winter sowing of 7 cultivars in Yigong Township(2177m)was conducive to the improvement of photosynthetic characteristics of flag leaves,and the photosynthetic rate and transpiration rate decreased first and then increased with the increase of altitude,while stomatal conductance and intercellular CO2 concentration increased first and then decreased with the increase of altitude.In Yigong Township(2177m),the photosynthetic characteristics of early and middle ripening and late ripening varieties were better,the photosynthetic characteristics of early and middle ripening and middle ripening varieties were better in Huidao Township(2748m),and the photosynthetic characteristics of early and middle ripening and late ripening varieties were better in Bayi District(2982m).(2)From the performance of antioxidant enzyme system and osmotic system of flag leaves,POD content and Pro content of 8 spring sowing varieties all showed a trend of first decreasing and then increasing with the increase of altitude,while SOD content showed a trend of first decreasing and then increasing with the increase of altitude.POD content and Pro content were higher in Bayi district(2982m),SOD content was higher in Duoji Township(3386m),and SOD content,POD content and Pro content were higher in the three sites in Huduo Township(2748m),Bayi District(2989m)and Duoji Township(3386m).The contents of POD,SOD and Pro of the 7 varieties sown in winter showed a decreasing trend with the increase of altitude,and the highest content was found in Yigong Township(2177m),and the SOD,POD and Pro contents of the early and middle ripe barley varieties were higher,while the SOD,POD and Pro contents of the middle ripe barley varieties were higher in Huiduo Township(2748m).(3)In terms of the yield of highland barley,the yield of 8 spring sowing varieties increased first and then decreased with the increase of altitude,and the overall yield was higher in Bayi District(2982m),with an average yield of 2042.93kg/hm2.The comprehensive performance of adaptability of varieties at different altitudes was analyzed by membership function.In Huiduo Township(2748m),the varieties were Zangqing 13,Zangqing 320,Zangqing 2000,Xila19,Longzihei,Zangqing 690,and Xila22,respectively.In Bayi District(2982m),the order was Tibetan green 320,Tibetan green 13,Tibetan green 2000,Hila 19,Hila 22,Tibetan green 690,farm species,Longzihei;In Duoji Township(3386m)for the order of Tibetan green 320,Tibetan green 690,Tibetan green 13,Longzihei,peasant species,Tibetan green 2000,Hila 19,Hila 22.The yield of the seven winter cultivars decreased first and then increased with the increase of altitude,and the highest yield was found in Bayi District(2982m),with an average yield of 3742.46kg/hm2.The comprehensive performance of adaptability of varieties at different altitudes was analyzed by membership function.In Yigong Township(2177m),there were District 02,Holly 19,Holly 15,Holly 1,Holly 18,and Guoluo.In Sheduo Township(2748m),District 19,02,01,Holly 15,Holly 1,Holly 18,Guoluo;In Bayi District(2982m)Holly 19,01,02,Holly 15,Holly 15,Holly 1,Guoluo.The results indicated that under the background of climate change,the barley production in Bayi district(2982m)of Nyingchi City,Xizang Province was more suitable,and the winter barley was better than the spring barley,and the middle and late maturing winter barley and middle maturing spring barley varieties had development potential.