5种外来入侵植物对小麦的化感作用

摘要

To provide references for controlling malignant weeds in wheat field of Luoyang,the seedlings of wheat was cultured by culture dish-filter paper method.Then,the allelopathic effects of aqueous extracts from S.oleraceus,S.asper,C.bisexualis,D.stramonium and V.persica leaves and stems on germination rate,seedling height and root length of wheat was determined and analyzed.Results:The inhibition effects of aqueous extracts on seed germination growth of wheat gradually increased with aqueous extract concentration increasing of S.oleraceus and the other three invasive plants species.Only with high concentrations (0.2 g/mL) D.stramonium did the plant aqueous extracts inhibit the seed germination of wheat.Five invasive plant species had strong allelopathic effects on the growth of seedling and roots of wheat,which presented promotion effects in low concentration and inhibition in high concentration.The extract of S.oleraceus leaves and stems in different concentration significantly inhibited the root length of wheat.The root growth was significantly inhibited compared to seedling growth of wheat.The comprehensive sensitivity of the allelopathic effects on the wheat of aqueous extracts of five invasive plant species leaves and stems was in the order of S.oleraceus＞ D.stramonium ＞ C.bisexualis＞ S.asper＞ V.persica.%为洛阳地区麦田中恶性杂草的防除提供参考依据,采用培养皿滤纸法培育小麦幼苗,测定苦苣菜、续断菊、小马泡、曼陀罗和阿拉伯婆婆纳5种入侵植物对小麦种子发芽率、幼苗苗高及根长生长的化感作用.结果表明:随茎叶水浸提液浓度的增加,苦苣菜、续断菊、小马泡和阿拉伯婆婆纳4种入侵植物对小麦种子萌发的抑制作用逐渐增大,而曼陀罗浸提液浓度达0.2 g/mL时才表现出明显的抑制作用;5种入侵植物茎叶水浸提液对小麦苗高具有低促高抑的化感作用,而根长除受苦苣菜的化感抑制作用外,同样受其他入侵植物低促高抑的化感作用,不同的是其抑制起始浓度总体小于苗高,而相同浓度处理下的抑制作用(RI绝对值)略大于苗高.综合效应平均值显示,5种入侵植物茎叶水浸提液对小麦的化感抑制作用依次为苦苣菜＞曼陀罗＞小马泡＞续断菊＞阿拉伯婆婆纳.