5种杀虫剂拌种处理对棉花苗蚜的田间防效及安全性评价

【目的】评价5种供试杀虫剂拌种处理对棉花苗蚜防效和棉花苗期的安全性,以获得拌种处理防效优于吡虫啉的替代药剂。【方法】测定棉籽7 d室内发芽势和14 d田间出苗率,评价供试杀虫剂在供试剂量下(4.20 g/kg种子)对棉花出苗和苗期生长的安全性。田间拌种处理,评价5种杀虫剂对棉花苗蚜的防控效果和持效期,并与常规药剂喷雾防治棉花苗蚜进行比较,评价2种方法对防控棉花苗蚜的效果。【结果】5种杀虫剂拌种处理均与空白对照没有显著性差异,对棉花出苗和苗期生长安全;在棉花播种后至25 d内,各供试杀虫剂均能有效控制棉花苗蚜种群,各处理间无显著性差异。播种后32 d各药剂处理防效均开始快速下降,其中50%吡蚜酮WG和20%噻虫胺CF防效最高,但仅为59.43%和55.52%。播种后39d仅20%噻虫胺CF防效为51.09%,其余处理百株蚜量接近或者高于空白对照;5%啶虫脒EC和10%吡虫啉WP对棉花苗蚜喷雾防控作用仅可维持3 d左右,至药后7 d,需继续采用药剂喷雾处理。【结论】与喷雾处理相比,拌种处理可以更长效的保护棉花,以更好的减少苗蚜的危害。5种杀虫剂拌种处理中,20%噻虫胺CF和50%吡蚜酮WG拌种防治棉花苗蚜均表现出了较好的防控效果。

Evaluation of the Safety and Control Effects of Five Insecticides Seed Dressing on Cotton Seedling Aphids

【Objective】 This study aims to evaluate the safety of five insecticides in the control of cotton seedlings and control effect to seedling aphids of cotton seed dressing in the hope of obtaining alternative insecticides whose control effects are superior to imidacloprid by the same treatment.【Method】 The authors evaluated the safety of the tested insecticides for cotton seed germination rate and seedling growth at the tested dose (4.20 g/kg seeds) by measuring the indoor germination potential of cotton seeds for 7 days and the field emergence rate for 14 days. In addition, the control effects and their persistence of the tested insecticides at the seedling period were evaluated by field seed dressing method. Finally we compared the spraying and seed dressing method on controlling cotton aphid to see their advantages and disadvantages.【Result】 Under the selected dosage, the results of indoor germination rate and field emergence rate revealed that there was no significant difference between the tested insecticides seed dressing and CK. It showed that 5 insecticides were safe to cotton emergence and seedling growth and the results of field control effects showed all the 5 insecticides could effectively control the population of cotton aphids and there were no significant difference between the treatments until 25 days after cotton sowing. Till 32 days after cotton sowing, the control effects of these insecticides begin to decline rapidly. Among them, 50% pymetrozine WG and 20% clothianidin CF had the highest control effects, but which were only 59.43% and 55.52%. On the 39 days after cotton sowing, only the control effects of 20% clothianidin CF was 51.09%, and the aphids per 100 plants of the remaining treatments were close to or higher than those of the CK. Spraying results showed that 5% acetamidine EC and 10% imidacloprid WP could only control cotton aphids well in 3 days, and the agent needed to be used again 7 days later.【Conclusion】 Compared with spray treatment, seed dressing could protect cotton more effectively and reduce the harm of cotton aphids better. Under the selected dosage, both 20% clothianidin CF and 50% pymetrozine WG all showed better effects on controlling cotton seeding aphids by seed dressing method, which could be used as alternative insecticides for cotton seedling aphids.