小麦-大豆间作中小麦对大豆磷吸收的促进作用

Facilitation of wheat to phosphorus uptake by soybean in the wheat soybean intercropping

采用塑料膜、30 μm尼龙网分隔以及不分隔两种作物根系的盆栽装置研究了小麦 -大豆间作种间磷吸收的促进作用。结果表明 ,两种作物根系用尼龙网分隔后 ,即种间磷竞争作用基本消除后 ,小麦对大豆磷吸收具有明显的促进作用 ,表现为大豆生物学产量明显提高 ,是塑料膜分隔的 2 .5倍 ,是无分隔的 4 .6倍。尼龙网分隔 ,大豆的根系活力高于塑料膜分隔 4 5.2 % ,达显著水平。此外 ,尼龙网分隔形成小麦根面 ,大豆的根系呈偏向小麦根面的分布 ,塑料膜分隔 ,则以大豆株为中心在两侧呈均匀分布。得出结论认为 。

A pot experiment was conducted to investigate the interspecific facilitation of wheat to the phosphorus uptake by soybean in the spring wheat soybean intercropping.The pots were separated into two compartments by either plastic sheet to eliminate root contact and any solute movement between two crop root systems or by nylon net (30μm) to prevent root contact between two crops while permitting solute exchange between them.In addition, a control treatment was used where no separation was made to the pot.Wheat plants were grown in one compartment and soybean in the other.The obvious facilitation of wheat to phosphorus uptake by soybean was observed in pot with net separation,where competition of wheat to phosphorus was eliminated.The biomass,root activity and phosphorus uptake of soybean for nylon net separation treatment were 150%,45.2% and 134% higher than those for plastic sheet separation treatment,respectively.In pots with nylon net separation,more roots of soybean were distributed near the nylon net on which wheat formed a dense root mat in the other side.In contrast,soybean roots distributed more or less evenly in the whole compartment for treatment of plastic sheet.It was supposed that the beneficial effect of soybean was resulted from the rhizosphere effect of wheat.