鬼针草和肿柄菊提取物对小白菜种子萌发的化感作用

采用培养皿滤纸法，研究入侵植物鬼针草和肿柄菊的水浸液和菌浸液对小白菜种子萌发的化感作用。研究结果表明:不同浓度的鬼针草、肿柄菊浸提液对同种受体植物种子萌发的化感效应不同，随着浸提液浓度的增大，其抑制作用越明显，其中鬼针草菌提液抑制效应最强。在根系生长方面，2种植物浸提液表现出低浓度促进、高浓度抑制效应，最适促进质量浓度为5 g·L-1，化感指数为047～058；最大抑制质量浓度为100 g·L-1，化感指数为-1。在株高生长方面，处理质量浓度25～50 g·L-1对小白菜株高的促进作用随浓度的增大而递增，其中肿柄菊菌浸液对株高的促进作用最强。可见，2种入侵菊科植物不同浸提液处理对同种植物不同器官的化感作用存在差异。小白菜发芽指数结果表明，4种浸提液化感抑制的强弱依次为:鬼针草菌浸液>肿柄菊水浸液>肿柄菊菌浸液>鬼针草水浸液。

The Allelopathy of Bidens pilosa and Tithonia diversifoliaExtracts on the Germination of Chinese Cabbage (Brassica campestris)

:The allelopathic effects of water extracts and bacteria extracts of Bidens pilosa and Tithonia diversifolia on seeds germination of Chinese cabbage were studied by petri dish filter paper method.The results showed that the allelopathy of different concentrations of the extracts on seed germination of the same acceptor plants were different.With the increase of the concentration of the extract,the inhibition effect became more obvious,and the bacterial extract of Bidens had the strongest inhibitory effect.In the aspect of root growth,the two plants extract showed low concentration promoting effect and high concentration inhibiting effect.The optimal promoting concentration was 5 g·L-1,the allelopathy index was 0.47 0.58The maximum inhibitory concentration was 100 g·L-1 and its allelopathy index was -1.In terms of plant height growth,the promoting effect of treatment concentration on plant height increased with the increase of the concentration from 2.5 g·L-1 to 50 g·L-1,and the promoting effect of the extract of T.diversifolia on plant height was strongest.In conclusion,the different extracts of two invasive compositae plants have different allelopathic effects on different organs of the same plant.According to the germination index of Chinese cabbage,the order of inhibition of four kinds of extraction liquefaction was B.pilosa fungus extract>T.diversifolia oaqueous extract>T.diversifolia fungus extract>B.pilosa oaqueous extract.