几种生物农药对梨园两种主要刺吸式害虫的毒力比较

梨木虱和绣线菊蚜是梨园中的两种主要刺吸式害虫,研究比较了4种植物源杀虫剂苦参碱、除虫菊酯、阿维菌素、烟碱.苦参碱对两者毒力作用,以助于控制其危害。实验结果表明,所选的4种植物源农药对绣线菊蚜和梨木虱均有一定的毒力作用,随着浓度的增加,死亡率提高,其中对绣线菊蚜的毒力作用普遍高于梨木虱,其致死中浓度分别为：梨木虱(苦参碱129.84 mg/L、除虫菊酯144.7 mg/L、阿维菌素90.74 mg/L、烟碱.苦参碱72.13 mg/L)绣线菊蚜(苦参碱18.79 mg/L、除虫菊酯17.79 mg/L、阿维菌素0.20 mg/L、烟碱.苦参碱 8.65 mg/L)。在实验所药剂浓度条件下,对梨木虱的防治效果为2.23%～77.27%,对绣线菊蚜的防治效果为43.2%～93.69%。四种杀虫剂对绣线菊蚜均有明显的防效,其中阿维菌素和 烟碱.苦参碱对梨木虱防效较好,可作为推荐药剂。

Toxicity Comparison of Bio-pesticides Against Two Main Pear Orchard Piercing-sucking Pests

Pear psylla (Psylla Chinensis) and spirea aphid (Aphis spiraeccla) are two kinds of main piercingsucking pests in pear orchard. We compared the toxicity of four bio-pesticides (matrine, pyrethrin, abamectin and nicotinic·matrine) against pear psylla and spirea aphid. The results showed that the four bio-pesticides had some inhibitory effect on spirea aphid and pear psylla, with the increase of concentration, the mortality increased, and the effect on spirea aphid was higher than that of pear psylla. The LC50 of pear psylla were matrine 129.84 mg/L, pyrethrin 144.7 mg/L, abamectin 90.74 mg/L and nicotinic·matrine 72.13 mg/L, that of spirea aphid were matrine 18.79 mg/L, pyrethrin17.79 mg/L, abamectin 0.2 mg/L and nicotinic · matrine 8.65 mg/L. The control effect on pear psylla ranged from 2.23% to 77.27% and the control effect on spirea aphid ranged from 43.2% to 93.69% at laboratory concentration. In conclusion, the four bio-pesticides showed good control effects on spirea aphid, and abamectin and nicotinic·matrine could be recommended as control agents on pear psylla.