外来入侵植物小飞蓬化感物质的释放途径

在室内以滤纸为载体用离体生测方法测定了小飞蓬(Conyza canadesiL.)全株水浸提物、茎叶淋溶物、根系分泌物及残体土壤分解物对萝卜(Raphanussativus L.)、黄瓜(Cucumis sativus L.)、马唐(Digitarias anguinalis(L.)Scop.)油菜(Brassica campestris L.)和小麦(Triticuma estivum L.)的化感效应,同时在温室内以土壤为载体通过盆栽植物浇灌的方法测定了小飞蓬茎叶淋溶物和根系分泌物对盆栽植物生长的影响。室内生测实验结果表明,小飞蓬全株水浸提物对5种受体种子的萌发和幼苗生长均有较强的抑制作用;根系分泌物、茎叶淋溶物和残体土壤分解物对受体种子的生长抑制作用不同,根系分泌物的活性高于茎叶淋溶物和残体土壤分解物。温室盆栽实验结果也表明,小飞蓬根系分泌物对受体生长的影响高于茎叶淋溶物。这些结果说明根系分泌是小飞蓬化感物质释放的主要途径之一。

The releasing mode of the allelochemicals in Conyza canadesis L.

The allelopathic effects of aqueous extract, root exudates, shoot leachates and decomposition from C. canadesis on radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), crabgrass (Digitaria sanguinalis (L.) Scop.), rape (Brassica campestris L.) and wheat (Triticum aestivum L.),were tested in petri dishes in laboratory. and the shoot leachates and root exudates were also tested in pot in greenhouse. The aqueous extract strongly inhibited the seedling growth of the tested plants. The root exudates, shoot leachates and decomposition inhibited the seedling growth of the tested plants differently, and the inhibitory effect of the root exudates was highest, The similar results were gotten from the greenhouse test. C. canadesis released the allelochemicals mainly through root exudates.