Study On Prepartion Development And Insecticidal Activity Of Piper Sarmentosum Roxb

Piper sarmentosum Roxb is a liana which belongs to piperaceae piper. It is a kind of common shade plant which widely spread in the south part of China and it lives creeping or climbing in the shrubbery humid valley, thick trees or the shade part of the hill. The research report revealed that the extract of P.sarmentosum has good biological activity of agricultural or medical. In order to go further in the research of the insecticidal activity, mechanism and the stability under different natural circumstances of the extract of P.sarmentosum so that it could be used in agricuture production. The root and stem part of the P.sarmentosum body was used in the investigation to get the raw extraction material that has the element of killing insects, which has been acquired by alcohol immersion and then using petroleum ether to extraction was used in the test to investigate the biological activity of the raw extraction material on Prodenia litura (Fabricius), Aleurodicus disperses Russell, Scirtothrips dorsalis Hood, Dysmicoccus neobrevipes (Beardsley), Phenacoccus solenopsis Tinsley and its biological activity on the common metabolic enzymes of Aleurodicus disperses Russell. The stability of the element of killing insects under different circumstances and the the preparation research using the raw extract of P.sarmentosum has also been conducted in the test. In conclusion:1. The result of the indoor activity of revealed that the raw extract of P.sarmentosum has good biological activity on P.litura, A.disperses, S.dorsalis, D.neobrevipes, P.solenopsis. The LC50of the2nd to5th instar of P.litura larvae processed with immersion method for24h was1.398mg·mL-1,2.175mg·mL-1,3.279mg·mL-1,10.434mg·mL-1,12.816mg·mL-respectively; the LC50of the nymph, pupa and adult of A.disperses processed for24h was2.207mg·mL-1,3.330mg·mL-1,1.625mg·mL-1, respectively, and the biological activity was improved as the hours prolonged; the LC50of the nymph and adult of S.dorsalis was0.300mg·mL-1and0.478mg·mL-1while the LC50of D.neobrevipes and P.solenopsis was0.821mg·mL-1and0.910mg·mL-1, respectively.2. Using the3rd instar larvae of P.litura as the index insect and the immunosorbent assay method. method as the evaluation system, the biological activity variation of the raw extract of P. sarmentosum activity on P.litura processed in different environment showed that the insecticidal activity element had a particularly strong stability of different concentration of acid and alkali and low temperature environment; but when being stored in high temperature environment for long hours the activity element of the raw extract of decompositioned P.sarmentosum and when processed in different kinds of light, sun light, ultraviolet lamp and fluorescent lamp had a strong effect on the insecticidal activity of it; that after12h and120h, the contact toxicity activity of mortality declined from80.00%,85.56%and8.89%to 1.11%,11.11%and21.11%, respectively, the decomposition rate of the raw extract of P.sarmentosum under the sun light condition reached98.61%whereas under dark, natural light and energy saving lamps conditions, it was relatively stable, the variation did not changed markedly.According to the decline activity of insecticide affected by light and using the first order dynamic model to fitting equation, the result showed that the attenuation equation of the insecticidal activity element of the raw extract of P.sarmentosum under the environment of sun light, ultraviolet lamp and fluorescent lamp were C=102.309e-0.0214t, C=97.377e-0.0095t and C=93.965e-0.0079t, respectively, and the half-life were32.38h,72.95h and87.72h under the same light conditions.On the foundation of the determination the degree of influence of sun light on the raw extract of P.sarmentosum, the inhibition effect on the decomposition in light was studied by the research of11kind of different photolysis of inhibitor. The result showed that among the11kind of photolysis of inhibitor, the inhibition effect of light stabilizer622and TBHQ was the greatest that after being processed for216h, the mortality of P.litura reached58.89%and54.44%. While the research on the inhibition effect of the two kinds of stabilizer revealed that the effect showed a certain correlation with its concentration, the higher the concentration of the photolysis of inhibitor, the clearer the photolysis inhibition effect the raw extract of P.sarmentosum.3. The mechanism of the insecticidal activity element of the raw extract of P.sarmentosum was investigated using the A.disperses adult. After being processed for24h and determinating the variation of some kinds of metabolic enzymes in A.disperses adult body. The statistics showed that the high concentration of the raw extract of P.sarmentosum has certain degree of inhibition effect on the AchE, CarE, ACP, ALP, GSTs, MFOs in A.disperses adult body; the inhibition effect on AchE was much clear and the effect of high concentration of it on CarE, GSTs, MFOs was inhibition whereas the effect showed to be inductive effect when the concentration of it was low. The difference in the effect of the raw extract of P.sarmentosum was not clear between different concentration levels.4. Guiding by pesticide agent producing-related theories and on the foundation of activity test and stability investigation, the preparation of the raw extract of P.sarmentosum-EC and P.sarmentosum-ME was studied systematically. The EC and ME was preparationed successfully using the raw extract of P.sarmentosum extractum as the raw material. The raw extract of P.sarmentosum-EC was composed of extractum10%, emulsifiers35%, solvents52.5%, light stabilizers and surfactant2.5%while the P.sarmentosum-ME comprised by extractum10%, emulsifiers21%, solvents27%, water39.5%, light stabilizers and surfactant2.5%. After a series of index test, the raw extract of P.sarmentosum-EC and P.sarmentosum-ME has met the requirement.The statistics of indoor toxicity test of the raw extract of P.sarmentosum-EC and P.sarmentosum-ME revealed that the two kinds of preparation has a very good biological activity on Lipaphis erysimi (Kaltenbach) and A.disperses. The LC50of the P.sarmentosum-EC to L.erysimi was0.129mg·mL-1and0.181mg·mL-1under the condition of put-in light stabilizer or not while the P.sarmentosum-ME to L.erysimi was0.233mg·mL-1and0.248mg·mL-1. The LC50of P.sarmentosum-EC put-in light stabilizer or not and the P.sarmentosum-ME put-in light stabilizer or not on the1st instar nymph of A.disperses was0.605mg·mL-1,0.612mg·mL-1,0.886mg·mL-1,0.875mg·mL-1, respectively; the LC50of2-instar nymph of A.disperses was0.898mg·mL-1,0.792mg·mL-1,0.805mg·mL-1,0.915mg·mL-1, respectively; the LC50of3-instar nymph of A.disperses was1.252mg·mL-1,1.536mg·mL-1,1.667mg·mL-1,1.495mg·mL-1, respectively; the LC50of pupa of A.disperses was1.733mg·mL-1,2.191mg·mL-1,2.818mg·mL-1,2.738mg·mL-1, respectively; the LC50of adult of A.disperses was0.151mg·mL-1,0.147mg·mL-1,0.169mg·mL-1,0.120mg·mL-1, respectively.The efficacy test in the field revealed that the control effect on the adult of L.erysimi and A.disperses. P.sarmentosum-EC was81.68%,77.48%and the P.sarmentosum-ME was91.28%,88.06%,what under the condition of concentration10mg·mL-1and lasted for24h the difference was not clear compared to the control effect of the control medicament of0.3%neem-EC and20%fenvalerate-EC.