Research The Preliminary Study On Water And Fertilizer Management Of Alfalfa In Salt-affected Land In Hetao Area

The effects of different irrigation rates,different irrigation times and different irrigation depth on the growth and quality of alfalfa in the second year were studied under different fertilization combinations,quantitative nitrogen and phosphorus and N,P and K fertilizers in the low fertility saline soil of the Hetao area.The results showed that the highest yield of alfalfa was 20707kg·hm-2 when the combination of N,P and K fertilizers was N1P5K5/667m2 and the highest yield increase rate was 72.7%.The highest plant height of alfalfa was 94.7crm and 62.7cm during the first and second stubble,respectively.The maximum yield was 22857kg at irrigation 1350t·hm-2 under the condition of N3P3/667M2.The maximum yield was 23598kg at irrigation750 t·hm-2 under the condition of N3P3K3/667m2.Irrigation could improve the crude protein and crude fat content of alfalfa under the application of two element fertilizer N3P3,but there is no significant difference for the content of crude protein and crude fat of alfalfa with the increase of irrigation amount.Irrigation 3 times(1050t·hm-2/times)has the highest yield of 20708kg·hm-2 and the best quality under the application of two element fertilizer N3P3.For the three stubbles of alfalfa have the best quality than others under irrigation amount of 1050t·hm-2 under the application of three element fertilizer N3P3K3,but there is no significant difference between different irrigation times.The application of irrigation under different fertilizer treatment can improve the yield and quality of alfalfa.Under the condition of different depth of irrigation,the highest total yield of alfalfa is 17060kg·hm-2 at the depth of 20cm and it is 45.450%higher as compared to surface irrigation alfalfa,and the highest plant height of the 3 stubbles are 86.9cm.97.9cm and 61.8cm.