为全面了解小桐子(Jatropha curcas L.)提取物的除草活性,以萝卜(Raphanus sativus L.)、苋(Amaranthus tricolor L.)、苏丹草〔Sorghum sudanense (Piper) Stapf〕和黑麦草(Lolium perenne L.)为实验材料,对小桐子果壳和枝叶的水、乙醇(体积分数95%)、正丁醇、乙酸乙酯、氯仿和石油醚粗提物的除草活性进行了生物测定,并从中筛选出抑制作用最强的水粗提物进行进一步的活性组分分离及其除草活性的生物测定。测定结果显示,小桐子果壳和枝叶的6种溶剂提取物(10g·L^-1)对供试的4种植物幼苗的根长和茎高均有不同程度的抑制作用,其中水粗提物和乙醇(体积分数95%)粗提物的抑制作用较强,且水粗提物对供试的4种植物幼苗的根长和茎高的抑制作用均在75%以上,显著高于其他溶剂粗提物(P<0.05);石油醚粗提物的抑制作用最小,均在10%以下。小桐子果壳和枝叶水粗提物的石油醚、氯仿、乙酸乙酯、正丁醇和水萃取物(10g·L^-1)对萝卜和苏丹草幼苗的根长和茎高均有不同程度的抑制作用,其中水、正丁醇和乙酸乙酯萃取物的抑制作用显著高于氯仿和石油醚萃取物,抑制率均在70%以上;水萃取物的抑制作用最强,抑制率均在80%以上;石油醚萃取物的抑制作用最小,抑制率均在10%以下。研究结果表明,小桐子果壳和枝叶的水粗提物具有一定的除草活性,其有效成分为极性较大的组分。

To overall understanding the herbicidal activity of extracts from Jatropha curcas L., the herbicidal activity of water, 95% ethanol, butanol, ethyl acetate, chloroform. and petroleum ether crude extracts from shell or branch and leaf of J. curcas was bioassayed using Raphanus sativus L., Amaranthus tricolorL., Sorghum sudanense (Piper)Stapf and Lolium perenne L. as experimental materials, and for water crude extract with the highest herbicidal activity, the active component separation and its herbicidal activity bioassay were conducted. The determination results show that all six solvent crude extracts(10g·L^-1) have the inhibition with different degrees to root length and stem height of four species seedlings, in which the inhibition of water and 95% ethanol crude extracts is stronger and significantly higher than that of other crude extracts (P< 0.05), with an inhibition rate of water crude extract to root length and stem height of four species seedlings above 75%. The inhibition of petroleum ether crude extract is the smallest among all crude extracts, with an inhibition rate below 10%. The petroleum ether, chloroform, ethyl acetate, butanol and water partitioned extracts (10g·L^{- 1})from water crude extract of shell or branch and leaf of J. curcas have different degree inhibition to root length and stem height of R. sativus and S. sudanense seedlings, in which water, butanol and ethyl acetate partitioned extracts all have higher inhibition effect than chloroform. and petroleum ether partitioned extracts, with an inhibition rate above 70%. The inhibition of water partitioned extract is the highest with an inhibition rate above 80%, while that of petroleum ether partitioned extract is the smallest with an inhibition rate below 10%.It is concluded that the water crude extract from shell or branch and leaf of J. curcas has a certain herbicidal activity, and its active components exist in the high polarity fractions.