不同栽植密度下紫花苜蓿叶生产量研究

Study on the Leaf Yields of Alfalfa(Medicago sativa) with Different Planting Densities

[目的]研究不同种植密度下苜蓿的叶生产量。[方法]以公农1号紫花苜蓿为试材,设5个种植密度处理,研究栽植密度对紫花苜蓿叶生产量的影响。[结果]在不同栽植密度下,紫花苜蓿单位面积分枝数、叶片数、茎重、叶重和干草产量5个性状在同一刈割时期及全年度各有不同程度的变化,且在某些密度处理间存在显著差异。苜蓿单位面积分枝数、叶片数、茎重、叶重和干草产量均以密度A处理(20 cm×20 cm)最多或最高,分别为855枝/m2、42 253叶/m2以及698.88、464.55和1 163.43 g/m2。相关分析表明,苜蓿的单位面积分枝数、叶片数、茎重和干草产量与单位面积叶重均呈线性正相关,对叶生产量的贡献大小依次为干草产量、茎重、叶片数和分枝数。[结论]5个栽植密度中,以密度A处理的叶生产量最高,其次为密度B处理(30 cm×30 cm)。

[ Objective] The aim was to study the leaf yields of alfalfa （Medicago sativa） with different planting densities. [ Method] With alfalfa Gongnong 1 as tested material, the treatments with 5 planting densities were set up to study the effect of planting density on the leaf yield of alfalfa. [ Result ] Under different planting densities, all the 5 characters of the branch number of unit area, leaf number, stem weight, leaf weight and hay yield of alfalfa changed to different extents in the same cutting stage and the whole year, and there was significant difference between some density treatments. The branch number of unit area, leaf number, stem weight, leaf weight and hay yield of alfalfa were all the maximum or the highest in treatment Density A （20 cm × 20 cm）, which were 855 branehes/m^2, 42 253 leaves/m^2 , 698.88, 464.55 and 1 163.43 g/m^2 resp. The correlative analysis showed that the branch number of unit area, leaf number, stem weight and hay yield of alfalfa all had a linear positive correlation with leaf weight of unit area, and the contribution size to the leaf growth yield was followed by the order as ： hay yield, stem weight, leaf number and branch number. [ Conclusion ] Among the 5 planting densities, the leaf yield was highest in the treatment with Density A, and the next was the treatment with Density B （30 cm ×30 cm）.