Effect Of Grassland Production Performance On Legume-Grass Forage Mixed Sowing In Northwest Hebei Province

The legume-grass mixtures can increase forage yield with stable productivity and improve forage quality.Based on the climatic conditions and forage utilization characteristics of Northwest Hebei Province,Medicago sativa,Bromus inermis and Elymus nutans were selected as candidate species.(1)Three mixed sowing combinations of Medicago sativa + Bromus inermis(MW),Medicago sativa + Elymus nutans(MP)and Medicago sativa + Bromus inermis + Elymus nutans(MWP)were used to establish a mixed sowing system with 5 mixed sowing ratios of 3:7、4:6、5:5、6:4 and 7:3.(2)There was cross sowing system which with Medicago sativa + Bromus inermis(MW)and Medicago sativa + Elymus nutans(MP)and every 15 days is a Medicago sativa sowing period,a total of 6 sowing dates was set in cross to the forage of grass.The study was conducted in the Zhangjiakou Experiment Station of National Forage Industry System on May 25 th 2019.In order to researched the effects of different sowing methods and mixed sowing combinations on grassland production performance,the main results are as follows:1.In the two years of mixed sowing system establishment,the advantage of plant height in the mixed sowing combinations was significant when the ratio of legume to grass was 3:7.The plant height of Medicago sativa which has great performance in the mixed sowing treatment was the same as the single sowing,and the grass was lower than single sowing.2.When the ratio of legume to grass was 3:7,the yield advantage of MW combination was significant higher than MP and MWP in every mixed sowing proportions.The fiber content of each mixed sowing treatment could be significantly reduced in 2019.MW4:6and MW5:5treatments could significantly improve the forage quality in 2020.3.MP7:3 combination could significantly improve the quality of forage in two years,MP3:7 treatment in 2019 and MP4:6 treatment in2020 had significant yield advantages.4.MWP7:3 and MWP5:5 treatment in the two yeas could significantly improve the forage quality.The yield advantages had significant enhance when MWP4:6 treatment in 2019,and MWP7:3treatment in 2020.5.The plant height of Medicago sativa and grasses has a negative correlation.Delay of Medicage sativa sowing date appropriately is conducive to the coexistence of mixed grass species.Sowing Medicago sativa with 15 days after sowing of grasses in 2019 and 45 days after sowing of grasses in 2020 could effectively increase vegetation coverage,increase forage yield and improve forage quality.Based on the analysis data of two years,Medicago sativa and Bromus inermis in the ratio of 3:7 have great yield performance,Medicago sativa and Bromus inermis and Elymus nutans in the ratio of7:3 can enhance forage quality effectively.Cross sowing Medicago sativa within 45 days to Elymus nutans can increase forage yield and improve forage quality effectively.In the construction of artificial grassland in the northwest of Hebei Province,the suitable planting mode can be selected based on the needed of yield or quality according to local conditions.