苜蓿根际土壤化感潜力的初步研究

Preliminary Study on Allelopathic Potential of Alfalfa Rhizospheric Soils

通过盆栽试验和发芽实验初步研究了4个生长年限(处理)的苜蓿地土壤化感作用强弱,其抑制活性强弱依次为:三年生苜蓿地>二年生苜蓿地>一年生苜蓿地>休闲地;在相同处理条件下,苜蓿对其他作物的化感作用强于其自毒效应。在一定年限内,苜蓿化感物质通过根系分泌、残茬分解和地上部分淋溶等途径进入土壤中,呈现出逐年富集的趋势。

Alfalfa (Medicago sativa L.) allelopathy has been widely reported aboard and at home. The allelopathic potential of alfalfa rhizospheric soils with different years of growth was primarily compared through bioassay in this paper. The results showed that the toxicity of alfalfa rhizospheric soils with different years of growth could be arranged in order of decreasing inhibition as follows: 3-year alfalfa rhizospheric soil, 2-year alfalfa rhizospheric soil, 1-year alfalfa rhizospheric soil and fallow soil. Under the same treatment, alfalfa allelopathic effect on other crops was stronger than its autotoxicity. Within some growth age range, the allelochemicals of alfalfa released into soil from root exudates, residues decomposition and leaching from aboveground could be accumulated year by year.