圆叶牵牛浸提液对白菜种子的化感作用研究

圆叶牵牛是成功入侵的一种外来杂草。植物的化感作用在外来杂草入侵中发挥着重要的作用。采用生物测定法研究了圆叶牵牛水浸提液对4个白菜品种种子萌发和幼苗生长的影响。结果表明:不同含量的浸提液影响白菜种子萌发的速率,低含量(1%、2.5%)的浸提液促进白菜丰抗78、津绿75的发芽,抑制率为-12.4%～-1.1%,但随着含量的提高,浸提液产生抑制作用,且逐渐增强,抑制率为9.7%～27.2%;不同含量的浸提液均能抑制西由78、早熟5号的发芽。浸提液均能抑制白菜根的生长,抑制率为12.5%～77.4%。低、中含量(1%～7.5%)的浸提液促进株高增加,抑制率为-47.4%～-5.3%,随着浸提液含量的升高,促进作用减弱并转为抑制作用,抑制率为9.10%～31.60%。综合分析,圆叶牵牛浸提液抑制白菜幼苗的生长发育,继而影响最终产量。从综合效应值来看,早熟5号受影响较小,是抗性最好的品种。

Study on the Allelopathy of Ipomoea purpurea on Cabbage Seed

Ipomoea purpurea was an invasive alien plant.The allelopathy played an important role in alien plant invasion.By means of laboratory bioassay,the allelopathic effect of water extract from Ipomoea purpure on seed germination and seedling growth was investigated using four cabbage varieties.The results showed that the germination seeds of cabbage were affected by different concentration of the water extract.Lower concentrations could increase the germination percentage of Fengkang 78 and Jinlu 75 and the inhibitive rates were-12.4%——1.1%.With the water extract concentration increasing,the effect became inhibition which showed enhanced trends with the inhibitive rates 9.7%-27.2%.The water extract decreased the germination percentage of Xiyou 78 and Zaoshu 5.Most water extract could restrain the growth of roots and the inhibitive rates were 12.5%-77.4%.Lower and middle concentrations could increased the height of seedling and the inhibitive rates were-47.5%——5.3%.Wtih the water extract concentration increasing,the promtion effect was weakened and even became a inhibition effect,with the inhibitive rates of 9.10%-31.60%.Zaoshu 5 showed relatively stronger resistance.