Study On Growth Characteristics In Different Growth Heights And Layered Cutting Height Of Alfalfa

Alfalfa Phabulous as materials harvested in the early flowering,then it was divided into every 1 Ocm layers based on height above ground. Growth characteristics, biomass and nutrient content of alfalfa in different layers was observed. The plants were divided into upper and lower parts.The biomass and nutrient content of upper and lower parts were contrasted. The concept "layered cutting height" and "layered height ratio" were presented.The results showed that:(1)Alfalfa biomass of different layers was different along the height. Branch length and leaf area of each layer closer to the bottom and top was smaller.Leaf stem ratio of each layer increased exponentially up to 2.30-4.77. The higher CP content was closer to the top of alfalfa plants, the top layer was higher than the lowest layer by 12.01%～17.37%. The lower NDF content was closer to the top of the plant, the top layer was lower than the lowest layer by 26.78～30.37%. ADF content was also closer to the top of the lower plants, the top layer was lower than the lowest layer by 24.79%～27.33%, The higher RFV was closer to the top of alfalfa plants, RFV of the top layer was 2.58～3.16 times the lowest layer.(2)Leaf-stem ratio and CP content in upper part were higher than that in lower part, NDF content and ADF content in upper part were lower than that in lower part.so quality of upper part was better than that of lower part. With the increasing of cutting height ratio, biomass of upper part was reduced, biomass of lower part was increased, leaf-stem ratio,CP content and RFV in two parts were both increased, NDF content and ADF content in two parts were both reduced.so with the increasing of cutting height ratio, quality of two parts were both changed for the better.