| Polygonum aviculare L. belongs to Polygonum L. which is an annual or perennialherbaceous plant. Polygonura aviculare L. distributes extensively in China and containsmany kinds of active constituents which have obvious pharmacological actions such asdiuresis, anti-hypertension, hemostasia and sterilization. Insecticidal activity of 58 kinds ofChinese medicine herbs were tested against Helicoverpa armigera by the research group.The results showed that Polygonum aviculare L had the best growth inhibition. Based onthe primary study, the bioactivity of powder and extracts of Polygonum aviculare L againstHelicoverpa armigera was tested by diet-incorporated method, furthermore, differentsolvents and different methods were used to ex. extract the active substances. The resultsare as follows:1. The bioactivity powder of the whole plant, root, stem and leaf of Polygonumaviculare L against Helicoverpa armigera was tested by diet-incorporated method. On the3rd and 5th day after the treatment, the growth-inhibitory rate reached 58.6％and 77.5％respectively. The average number of eggs laid per female decreased 400-500 than the CK.The insecticidal activities of root, stem and leaf of Polygonum aviculare L were testedagainst Helicoverpa armigera. The results indicated the roots of Polygonum aviculare Lhad inhibition to growth significantly higher than the others.2. Seven different solvents were used to extract Polygonum aviculare L.. The distillrates were: water＞methanol＞95％ethanol＞chloroform＞acetone＞ethyl acetate＞petrol ether. The bioactivities of extracts against Helicoverpa armigera were also studiedand the results showed that the 7 kinds of extracts of Polygonum aviculare did not havecontact toxicity obviously. In which 95％ethanol solvent and the death rate was only26.7％. The antifeeding activities of ethyl acetate extracts and methanol extracts wereobvious. The antifeeding rate was 79.2％and 63.9％respectively. The growth inhibitionactivities against the larvae ofHelicoverpa armigera were: ethyl acetate＞methanol＞95％ethanol＞petrol ether＞chloroform＞water. The ethyl acetate extracts had the highestbioactivity, the average weight of treated larvae decreased 210mg on the 5th day. Themethanol extracts showed best inhibition on pupation and the pupation rate was 76.7％.3.5 kinds of methods were used to extract with ethyl acetate and the distill rates were:Soxhlet extraction＞Ultrasonic and vibratory extraction＞Interval-vibratory extraction＞Cold soak extraction＞Ultrasonic extraction. The bioactivities of extracts by Soxhlet, Ultrasonic and vibratory, Interval-vibratory was higher than that of Cold soak andUltrasonic against the Helicoverpa armigera. But the activity of Soxhlet extraction,Ultrasonic and vibratory extraction, Interval-vibratory extraction has no evident difference.4. The Polygonum aviculare L was extracted with ethyl acetate by Interval-vibratoryextraction. The bioassay showed that the contact toxicity of the extract was low and themortality rate was below 20％, while antifeeding activity was obvious. The AFC50 againstHelicoverpa armigera, Plutella xylostella andPieris rapae were 0.02211 g/m, 0.09103 g/mland 0.1911 g/ml respectively.5. The ethyl acetate extracts of Polygonum aviculare L was fractioned by liquid-liquidpartition method with petrol ether, chloroform, ethyl acetate and n-Butanol. The extractrates were: petrol ether＞chloroform＞n-Butanol＞ethyl acetate. Biological activity of theextracts against Helicoverpa armigera L was tested. The results showed that the petrolether and chloroform extracts had significant growth inhibition activities; the mortality rateof n-Butanol extracts was the highest.6. 8 parts were obtained from the petrol ether extracts by column chromatograghy.They showed different growth inhibition against Helicoverpa armigera L expect for 1 and2. The inhibition rote of 4 and 6 was 67.33％and 77.52％respectively on the 5th day afterthe treatment.
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