Selection Of Phosphorus Efficient Alfalfa Varieties In Horqin Sandy Land

It is necessary to utilize the biological characteristics of plants to explore their potential capacity,and at the same time screen,identify and promote varieties with high phosphorus utilization efficiency,so as to improve the utilization efficiency of phosphorus resources and alleviate irreversible losses caused by excessive application of phosphorus fertilizer to the ecological environment.At the same time,the use of plant characteristics to improve the efficient use of phosphorus nutrition has become a substitute means to improve soil nutrient status.In view of the above situation,two phosphorus application levels(90kg/hm~2and 270kg/hm~2)and different alfalfa varieties(Juneng 401,3010,4030,etc.)were set in this experiment to screen out phosphorus efficient alfalfa varieties by measuring CNP stoichiometric characteristics,CP,NDF,ADF and yield.It provides theoretical basis for efficient utilization of alfalfa phosphate fertilizer in Horqin Sandy land.The results show that:1.Under low phosphorus stress,the first crop yield,the second crop yield and total yield of different alfalfa varieties were significantly different.The first crop yield of Baimu202 was the highest,and the first crop yield of Sped was the lowest.The first crop yield of Juneng 401,Speid,Luthler,Challenger,Baimu 401,WL168HQ and WL298HQ under low P treatment was significantly lower than that under normal P treatment(P<0.05).The second crop yield of 4020 was the highest,and the second crop yield of WL168HQ was the lowest.The second crop yield of Juneng 401,3010,Baimu 341,Challenger,Baimu 202,Baimu 401,WL168HQ,WL343HQ,WL298HQ,Zhongmu No.1,Gongnong No.1 and Zhaodong alfalfa under low P treatment was significantly lower than that under normal P treatment(P<0.05).Qisi T had the highest total output,WL168HQ had the lowest total output,and juneng 401,Sped,Baimu 341,Lussler,Challenger,Baimu 401,WL168HQ,WL343HQ,WL298HQ,Zhongmu No.1 and Gongnong No.1 under low P treatment were significantly lower than those under normal P treatment(P<0.05).2.Under low P stress,the nutritional quality of different alfalfa cultivars in the first crop was significantly different,zhongmu No.1 had the highest CP content,and The CP content of Juneng 401,4030,Juneng 7,4010,Adina,Baimu 401 and Gongnong No.1under low P treatment was significantly lower than that under normal P treatment(P<0.05).The RFV of Knight T was the highest,and the RFV of 4030,Spader,Catro,WL358HQ,Gongnong No.1 and Zhaodong alfalfa under low P treatment was significantly lower than that under normal P treatment(P<0.05).The nutrient quality of the second crop of alfalfa was also significantly different among different varieties,with the highest CP content of Lucyla,and the CP content of Juneng 401,4030,Juneng 7,4010,Cathro,Baimu 371 and Challenger under low P treatment was significantly lower than that under normal P treatment(P<0.05).The RFV of Spader was the highest,and the RFV of Juneng7 and Zhaodong alfalfa under low P treatment was significantly lower than that under normal P treatment(P<0.05).3.Alfalfa varieties with different P efficiency were divided into three categories by comprehensive evaluation and analysis,Phosphorus medium efficiency type:Zhongmu No.1,WL343HQ,WL298HQ,WL168HQ;Phosphorus medium efficiency type:Zhaodong Alfalfa,Knight T,Baimu 401,Gongnong No.1,Da Yinhe,Baimu 341,Sped,Challenger,Luthule,WL358HQ,Knight 2,4020,3010;Phosphorus low efficiency type:Juneng 401,Baimu 371,Baimu 202,4030,Adina,Juneng 7,4010,Cathro.