【摘要】 以龙胆的全草为试材,基于均匀设计法研究了龙胆全草的不同提取液对棉蚜的触杀和拒食作用。结果表明,乙醇浸提液对棉蚜具有较高的触杀作用。水蒸气蒸馏液对棉蚜具有较强的拒食作用。乙醇浸提液对棉蚜48 h的致死中浓度(LC50)为17.663 5 mg/mL,水蒸气蒸馏液对棉蚜24、48 h的拒食中浓度(AFC50)分别为18.975、17.362 mg/mL。丙酮浸提液对棉蚜的触杀和拒食作用不显著。龙胆全草的乙醇浸提液和水蒸气蒸馏液对棉蚜56 h的同时触杀和拒食的活性浓度初步筛选结果表明,乙醇浸提液54.34 mg/mL和水蒸气蒸馏液59.05 mg/mL联合使用对棉蚜同时触杀和拒食活性作用最好,死亡率达100%。更多还原

【Abstract】 The whole herbal plants of Gentiana scabra Bunge were used as the experimental materials to study their activity against Aphis gossypii by uniform design.The results showed that ethanol extract had high effectiveness of contact death effect on A.gossypii,with the LC50 as 17.663 5 mg/mL in 24 h.Distilled liquid had strong antifeeding effects on A.gossypii,with the AFC50 as 18.975 mg/mL and 17.362 mg/mL in 24/48 h,respectively.Acetone extracts had insignificant effects on A.gossypii.The results of preliminary screening showed that ethanol extract with 54.34 mg/mL and distilled liquid with 59.05 mg/mL had strong effects on A.gossypii,with the death rate as 100% in 56 h.更多还原