| In recent years, using insecticidal active compounds of the natural compounds manufacture new pesticide directly or synthesizing leading compounds manually or improve their activity by modify synthesis after them were searched from the natural compounds has been a hotspot of insecticidal research and one of the major methods to manufacture new pesticide. Ginkgo biloba L. Sarcotesta was generally discarded and regarded as waste in the agricultural production, which not only waste material but also pollute environment. For the purpose of utilizing this waste effectively, insecticidal activity, active ingredient and formulation of Ginkgo biloba L. Sarcotesta were studied in this paper.1. The topical application, residual toxin method, dipping insect method and growth rate method were used to determined the contact activitise or the inhibitory activities on hyphae growth of the MeOH extract of Ginkgo biloba L. sarcotesta against Lipaphis erysimi, Panonychus citri, Plutella xylostella and seven species of pathogenic fungi: Fusarium oxysporum f. sp. Niveum (E. F. Smith)Synder & Hensen, pestalotia mangiferae P.Herm, Thielaviopsis paradoxa (de Seynes) V. Hohnel, Glorosprium musarum Cookeet Mass, Alternaria kikuchiana (Fr) Keissl, Mycosphaerella sentina(Fr.) Schroeter,Sphaceloma fawcettii Jen kins, respectively. The result showed the MeOH extract of Ginkgo biloba L. sarcotesta had high contact toxicity to Lipaphis erysimi, Panonychus citri and Plutella xylostella, with the LD50 (or LC50) values being 0.4796μg·♀-1, 1.4956 g·L-1 and 2.7756 g·L-1, respectively. But on the concentration of 10g/L, its inhibitory activities on hyphae growth against seven species of pathogenic fungi didn't exceed 30%.2. Lipaphis erysimi was used as insect to study active ingredient of Ginkgo biloba L. sarcotesta with activity-directed isolation method in this paper. Two insecticidal active compounds were isolated from Ginkgo biloba L. sarcotesta, and they were measured as bilobol and ginkgoic acid after analyzing with MS,IR,1H- NMR,13C-NMR and consulting literatures. After further testing, bilobol showed high contact toxicity to Lipaphis erysimi and Plutella xylostella, with the LD50 (or LC50) values being 0.5824μg·♀-1and 2.0613g·L-1, respectively. But it don't showed insecticidal active against Panonychus citri. And ginkgoic acid showed high toxicity to Lipaphis erysimi, Panonychus citri and Plutella xylostella, with the LD50 (or LC50) values being 0.3328μg·♀-1, 2.9110g·L-1 and 4.6002 g·L-1, respectively.3. The MeOH extract Ginkgo biloba L. sarcotesta was used as material manufactured insecticides. By screening of solutions and emulsifiers, the 20% EC and 10% EW of Ginkgo biloba L. sarcotesta with great emulsibility and stability were manufactured after the quality examination of hot and cold storage.4. The contact toxicity of 20% EC and 10% EW of Ginkgo biloba L. sarcotesta to Lipaphis erysimi were determined by leaf spraying method. The result showed 20% EC and 10% EW of Ginkgo biloba L. sarcotesta had high contact toxicity to Lipaphis erysimi, with the LD50 (or LC50) values of 1.39g/L and 2.56g/L, respectively. The indoor insecticidal activities of two preparations and the preparations after storing against Lipaphis erysimi were determined. Without storing, the 24h adjust mortality of 500 times 20% EC and 300 times 10% EW of Ginkgo biloba L. sarcotesta against Lipaphis erysimi were 57.23% and 72.62%, respectively. After cold and hot storing, the 24h adjust mortality were 55.14%, 58.77% and 70.11%, 70.45%, respectively. This result approved the insecticidal activities of preparations won't change after cold and hot storing.5. Field control efficiency of two preparations on Lipaphis erysimi and Panonychus citri were measured in this study. After treating of 7d, the control efficiency of 100, 200 and 400 times 20% EC of Ginkgo biloba L. sarcotesta on Lipaphis erysimi were 100%, 93.5% and 53.9%, respectively. After treating of 7d, the control efficiency of 50, 100 and 200 times 10% EW of Ginkgo biloba L. sarcotesta on Lipaphis erysimi were 98.2%, 95.3% and 48.7%, respectively. And the control efficiency of two preparations on Panonychus citri was lower than Lipaphis erysimi. After treating of 7d, the control efficiency of 100, 200 and 400 times 20% EC of Ginkgo biloba L. sarcotesta were on Panonychus citri 77.6%, 73.7% and 47.2%, respectively. After treating of 7d, the control efficiency of 50, 100 and 200 times 10% EW of Ginkgo biloba L. sarcotesta on Panonychus citri were 74.5%, 69.6% and 43.9%, respectively. So we suggested that 20% EC and 10% EW of Ginkgo biloba L. sarcotesta should be diluted to 200 and 100 times to control Lipaphis erysimi. And they have great potentialiality to be used on agricultural production.
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