Abstract:

In order to find the extraction method of herbicidal compounds from Pittosporum tobira (Thunb.) Ait. leaves, the effects of the ethanol extraction and different solvent extract phases of P. tobira leaves on seedlings growth of Lactuca sativa, Triticum aestivum, Lagopsis supine and Echinochloa crusgalli were studied with method of grinded plant tissue powder mixed with agar (PPA). The results showed that, the growth of 4 kinds of receiver plants seedlings were inhibited differently by ethanolic extract of P. tobira leaves, and the susceptibility of L. sativa, T. aestivum, and L. supine were higher than that of E. crusgalli. The petroleum ether, ethyl acetate, n-butanol and water partition from ethanolic extracts had higher inhibitory effect on the growth of 4 kinds of receiver plants, although the inhibitions were different. The results suggested that, the ethanol extraction and its different solvent extract phases of P. tobira all had the high growth inhibitory substances, but the substance varieties might be more complicated.