茜草等23种植物对棉铃虫生物活性的研究

为寻求对有害生物高效、非靶标生物安全、对人类健康和生态环境安全的生物农药,本研究采用饲料混毒法,测定了23种植物干粉对棉铃虫生长发育的影响。结果表明,茜草、儿茶、白头翁、丹皮和香铃子表现出较强的生长发育抑制作用。以茜草的影响最明显,体重抑制率最大时为84.87%,试虫体重仅43.15 mg,而对照高达285.27 mg;幼虫历期达19 d,比对照延长了5 d;尤其对成虫产卵有明显的影响:产卵量比对照约少700粒,产卵历期缩减了3 d,卵的孵化率也仅有67.0%。茜草不同溶剂提取物对棉铃虫均表现出良好的拒食活性,但触杀活性和胃毒活性比较低。95%乙醇提取物的拒食活性最高,石油醚提取物的胃毒活性最高;各溶剂提取物的触杀活性均较低,校正死亡率均在5%以下。

Studies on insecticidal activity of 23 plant powders against Helicoverpa armigera

In order to seek an efficient,human and eco-friendly bio-pesticide,the growth and development effects of the powder of twenty-three plants on the larvae of Helicoverpa armigera,including Rubia cordifolia L,Acacia catechu Willd and Pulsatilla chinensis etc,were tested by diet-incorporated method.The results showed that the powder of R.cordifolia L.,A.catechu Willd,P.chinensis,Paeonia suffruticosa Andr and Toona sinensis Roem had much effect on the larvae of H.armigera.And R.cordifolia L.was the best one,whose highest growth inhibitory rate reached 84.87% at the 5th day after treatment.At that moment the weight of the larvae of H.armigera tested by R.cordifolia L.was only 43.15 mg,but the weight of the contrast larvae of H.armigera was 285.27 mg.The larvae duration lasted 19 days,5 more days than usual.Also it had much effect on the adult,especially on the egg-laying: the egg laying period was 3 days shorter and the egg hatching rate was only 67%.The extracts of R.cordifolia L.by different solvents had high antifeeding effects and low the contact toxictity and stomach toxicity.The 95% Ethanol extract had the highest antifeeding effects,the Petroleum ether extract had the highest stomach toxicity,and the contact toxictity of four solvent extracts were all below 5%.