施肥水平对甘蔗/大豆间作体系中植株 生长及养分积累的影响

采用盆栽方法研究了不同施肥水平下间作对甘蔗和大豆生长的影响以及间作优势。结果显示：间作大豆的各项植株指标与单作大豆差异不显著，不施肥可以刺激单作和间作大豆根系的生长，增加大豆根瘤数和根瘤重，而间作甘蔗各项指标大多数显著低于单作甘蔗，在不施肥的情况下下降幅度加大，但总根长两者间差异不显著；间作甘蔗的氮、磷、钾积累量均小于单作的甘蔗，以钾的降低幅度最大，而间作大豆仅在不施肥的情况下磷、钾的积累量显著低于单作大豆，氮素在四种处理间差异不显著；两种施肥水平下间作的土地当量比（LER）均大于1，说明间作有明显的优势，并且间作的氮、磷、钾总养分累积量高于单作，由此可见甘蔗与大豆间作优势不是表现在个体上，而是表现在提高土地利用率上。

Effect of fertilizer levels on plant growth and nutrient accumulation in sugarcane/soybean intercropping system

In this study, the plant growth in sugarcane/soybean intercropping system and the intercropping advantage were evaluated by plot experiments under different levels of fertilizer. The results revealed that plant growth parameters had no significantly difference between intercropping soybean and sole cropping soybean, while the root parameters, the number of nodules and the weight of nodules were improved under no fertilizer. However most of growth parameters in intercropping sugarcane decreased, but the total root length of sugarcane was not affected by intercropping. The accumulation amount of nitrogen,phosphorous and potassium in intercropping sugarcane was significantly lower than that in sole cropping, whereas only accumulation amount of phosphorus and potassium in intercropping soybean was significantly lower than that in sole cropping soybean under no fertilizer. The LER value of normal fertilizer and no fertilizer were all up to 1, which indicating that there were intercropping advantages under two fertilizer levels. The total accumulation amount of nitrogen, phosphorous and potassium in intercropping system was higher than those in sole intercropping. All these results indicated that the intercropping advantage did not show on the single plant but on enhancing land use rate.