Allelopthy Of Rehmannia Glutinosa Libosch On Sesame

Rehmannia glutinosa Libosch is a kind of allelopathic medicinal plant,it had two thousand years cropping history,Jiaozuo of Henan province was the first distributing area to grow this plant. Sesame is a important oil plant in Henan province,annual planting area and yied were 0.313 million hektare and 0.112 million ton separately,account 28% yeid for all country.There existed some problems that it was not suitable to crop sesame after Rehmannia glutinosa Libosch.In this paper, the continuous cropping soil and leaves of Rehmannia glutinosa Libosch were extracted and isolated by silica gel.With the bioactivity of geminnation of sesame,the extracts were identificated and quantified by GC-MS and HPLC.Through this experiment,we also got several important conclutions:(1)The extract of Rehmannia glutinosa Libosch’s leaves inhibited geminnation of sesame more strongly than the extract of the root and caudex.The results showed the leaves had more allelochemicals.(2)The extract from the leaves which were isolated by silica gel and identificated by GC-MS,we find a possible allelochemical which was Dodecanoic acid had strong effect on root and shoot of sesame.(3)A strong effect of component was 2Fr4 which was extracted from leaves and isolated by silic gel.Though expriment of potted plant,the component of 2Fr4 had a accord effect on sesame with continuous cropping soil of Rehmannia glutinosa Libosch, the sesame seedling height and weight were loss;protected enzymes activity decreased and the contain of MDA rose.(4)Through farther expriments,we find the extract of Ethyl acetate from leaves contain the main allelochemicals.(5)With the instrumentality of GC-MS and HPLC,we got some possible allelochemicals which were 6-(3-hydroxy-but-1-enyl)-1,5,5-trimethyl-7-oxobicycl (4,1,0)hptan-2-ol;4-hydroxy-3,5,6-trimethyl-4-(3-oxo-1-butenyl)-2-cyclohexen-1-one and a kind yellow crystal.This yellow crystal was possibly quantified as Apigenin by Ifra-red spectroscopy.