Screening And Investigation Of Insecticidal Plant Resource And Preliminary Study Of Termopsis Lanceolata In Ningxia

In this study, through systemic investigation of insectical plant resources in Ningxia, andon the basis, the plant with high pesticides activity which mainly aimed at the wolfberryaphids, phylloxera and thripidae were screened. And the research content of plant resourcesutilization from thermopsis lanceolata to avoid the adverse impact in resource utilization.This research mainly obtains the following results:1. Through the system investigation in Ningxia, we collected pesticide activitycharacteristic plants of29families and58genera and75species, which were mainlyconcentrated in the Ranunculaceae, legume, Euphorbiaceae. Among them, Sophoraalopecuroides, Cynanchum komarovii, Peganum harmala, Thermopsis lanceolata,Euphorbiaesula had a wide distribution and abundant population density in Ningxia.2. Extraction of plant active substances with different solvents, we conducted alaboratory bioassay of aphifs, thrips, nymphal development, and found that Aconitumflavum,Stellera chamaejasme,Thermopsis lanceolata,Euphorbia esula have highinsecticidal activity against pests wolfberry.3. The determination results of toxicity, the LC50of4kinds of plant extracts againstAphis sp. were822.90,529.73,258.90and303.79mg/L respectively. Thermopsis lanceolataand Euphorbia esula had the better performance than other two species.4. In order to cytisine as the standard, we determined by Spectrophotometry that theactive substance of cytosine in different parts of the Termopsis lanceolata was seed> leaf>root> stem. Furthermore, we determine the active substances at different growth stages ofTermopsis lanceolata was fruit> flower> seedling.5. Bioassay results showed that, the different parts of active extracts of Termopsislanceolata at the dose of0.05g/mL,24h after correction of Chinese wolfberry aphid mortalitywere61.64%,50.47%,59.16%,63.80%. The activity extracts of seedling, flowering, fruitingof Termopsis lanceolata at the dose of0.05g/mL,24h after correction of Chinese wolfberryaphid mortality were49.46%,56.81%,58.39%. 6. Through the analysis and comparison, we found that active substance of cytosinevaried at different growth stages and parts of Termopsis lanceolata. Seed and leaf had the bestinsecticidal activity at the fruiting period.