用甲醇对广西乐业天坑14种植物不同部位(18个样品)进行冷浸提取,室内测定各甲醇粗提物对白背飞虱和褐飞虱的生物活性。结果表明:处理后48 h,伊桐叶、种子和树皮及牛耳枫果和紫苏对白背飞虱和褐飞虱的触杀活性较高,白背飞虱和褐飞虱的死亡率达80%以上,伊桐果皮和扫把枝对白背飞虱和褐飞虱的触杀活性为50%~80%;蛇床子果对白背飞虱为高触杀活性,而对褐飞虱为中等触杀活性;商陆对白背飞虱为中等触杀活性,对褐飞虱为低触杀活性;其余8种植物甲醇粗提物对白背飞虱和褐飞虱的触杀活性均在50%以下;72 h后,伊桐树皮和种子、蛇床子果、牛耳枫果甲醇粗提物对白背飞虱和褐飞虱的产卵忌避活性都达到80%以上,其余植物甲醇粗提物对白背飞虱和褐飞虱的产卵忌避活性都在60%以下;有高触杀活性和高产卵忌避活性的植物甲醇粗提物对白背飞虱和褐飞虱4龄若虫的拒食活性大小顺序为伊桐叶、伊桐种子、伊桐果皮、蛇床子果、牛耳枫果、伊桐树皮。
Bioactivity of 18 samples of crude methanol extracts from 14 species of plants extracted by cold soak method against Sogatella furcifera and Nilaparvata lugens were tested in this paper.The results showed that the leaf,seed and bark of Itoa orientalis Hemsl,the fruit of Daphniphyllum calycinum Benth and the whole plant samples of Perilla frutesens L.showed high contact toxicity with the corrected mortalities against the macropterous of S.furcifera and N.lugens both over 80%.The contact toxicity of the peel of I.orientalis and the whole plant samples of Baeckea frutescens Linn.were between 50% and 80% after treated for 48h.The sample of Cnidium monnieri(L.) Cuss had high contact toxicity to S.furcifera and moderate toxicity to N.lugens.Phytolacca acinosa Roxb.showed moderate contact toxicity to S.furcifera and low toxicity to N.lugens.The contact toxicity of the other 8 plant samples to S.furcifera and N.lugens were lower than 50%.The oviposition repellent rate of the seed and bark of I.orientalis Hemsl,the fruit samples of C.monnieri(L.) Cuss.and D.calycinam Benth.to S.furcifera and N.lugens were all over 80% while the repellent activity of the rest plant samples were all lower than 60% after treated for 72h.The antifeedant activities of the plants with high contact toxicity and repellent activity were tested.The leaf of I.orientalis Hemsl showed the highest antifeedant activity against the 4th instar nymphae of S.furcifera and N.lugens,followed by the seed of I.orientalis Hemsl,the peel of I.orientalis Hemsl,the fruits of C.monnieri(L.) Cuss and D.calycinam Benth and the bark of I.orientalis Hemsl.