Effects Of Planting Patterns And Manure Amount On The Production Characteristics Of Organic Forages

The objective of this study was to explore the response of forage yield and forage quality under seven kinds of planting patterns and five gradients of organic fertilizer application in Wuling mountainous areas,which was determined the ideal mixed combination.The three forage species which included Medicago sativa,Dactylis glomerataand,Lolium perenne were selected.The germination parameters of three forage species were tested,according to the characteristics of calcium concentration and the acidity of the soil in the Guizhou karst regions.The artificial grasslands were established by mixing Medicago sativa+Dactylis glomerata?ZY?,Medicago sativa+Lolium perenne?ZH?,Dactylis glomerata+Lolium perenne?YH?and Medicago sativa+Dactylis glomerata+Lolium perenne?ZYH?and with only one species?DZ,DY and DH?.The effects of different planting patterns and gradients of organic fertilizer application on the yield and nutrient quality of pasture were analyzed.The main results are as follows:1.The germination parameters of forage seed under different pH and CaCl₂concentration were Medicago sativa>Dactylis glomerata>Lolium perenne.The growth of seedlings and root length showed acid promotion and alkaline inhibition.The effect of CaCl₂ concentration on the bud length and root length growth of the seedlings was generally manifested as low concentration and high concentration.2.The maximum growth rate of organic forage was 0.66 cm/d;the maximum absolute growth rate was 5.08 g/m²/d,which appeared in Medicago sativa grassland.In the mixed grassland,the largest absolute growth rate of Medicago sativa+Lolium perenne was 4.82 g/m²/d,which indicating the accumulation of biomass per unit area was the highest;the maximum relative growth rate of unicast grassland appeared in Medicago sativa grassland was 0.08 g/m²/d;and the relative growth rate of mixed grassland was 0.07 g/m²/d.At this time,the pasture regeneration rate was the fastest,and the utilization of environmental resources was the highest.3.As the amount of organic fertilizer applied increased,the yield and quality of pasture increased,when the amount of organic fertilizer was greater than or equal to20 t/hm².The quality of the hay in this experiment was special or first grade.4.The annual yield of fresh grass was the highest?56.50 t/hm²?in fresh grass with Dactylis glomerata+Lolium perenne combined grassland in unicast and mixed grassland.The optimum manure amount of unicast grassland and mixed grassland was20—30 t/hm² and 20—40 t/hm²,respectively.From the perspective of more nutrients,the optimum fertilization amount of CP,EE,CF,ASH and NFE of forage was 13.55—39.92 t/hm².Under different planting patterns and gradients of organic fertilizer application,considering the factors such as emergence,speed of growth,yield and quality of organic forage,Medicago sativa+Lolium perenne combination was ideal for artificial grassland establishment,when the amount of fertilizer was 20 t/hm².