PDF(Pubmed)
Abstract：
The tarnished plant bug, (TPB) Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) is a key pest of cotton in the midsouth region and some areas of the eastern United States. Its control methods have been solely based on chemical insecticides which has contributed to insecticidal resistance and shortened residual periods for control of this insect pest. This study was conducted over a two-year period and examined the efficacy and residual effect of four commercial insecticides including lambda-cyhalothrin (pyrethroid), acephate (organophosphate), imidacloprid (neonicotinoid), and sulfoxaflor (sulfoxamine). The effectiveness and residual effects of these insecticides were determined by application on cotton field plots on four different dates during each season using three different concentrations (high: highest labeled commercial dose (CD), medium: 1/10 of the CD, low: 1/100 of the CD) on field cotton plots. Four groups of cotton leaves were randomly pulled from each treated plot and control 0-, 2-, 4-, 7-, and 9-days post treatment (DPT) and exposed to a lab colony of TPB adults. One extra leaf sample/ plot/ spray /DPT interval (0-2-4-7-9-11) during 2016 was randomly collected from the high concentration plots and sent to Mississippi State Chemical Laboratory for residual analysis. Mortality of TPB adults was greatest for those placed on leaves sprayed with the organophosphate insecticide with mortalities (%) of 81.7±23.4 and 63.3±28.8 (SE) 1-day after exposure (DAE) on leaves 0-DPT with the high concentration for 2016 and 2017, respectively, reaching 94.5±9.5 and 95.4±7.6 6-DAE each year. Mortality to all insecticides continued until 9 and 4-DPT for high and medium concentrations, respectively. However, organophosphate (39.4±28.6) and pyrethroid (24.4±9.9) exhibited higher mortality than sulfoxamine (10.6±6.6) and the neonicotinoid (4.0±1.5) 7-DAE on 9-DPT leaves with the high concentration. Based on our results using the current assay procedure, TPB adults were significantly more susceptible to contact than systemic insecticides and due to its residual effect, organophosphate could kill over 80% of the TPB population 7-DPT.
摘要：
玷污的植物虫，（TPB）LyguslineolarisPalisotdeBeauvois（半翅目：Miridae）是中南部地区和美国东部某些地区棉花的主要害虫。其控制方法仅基于化学杀虫剂，化学杀虫剂有助于产生杀虫抗性并缩短了控制该害虫的剩余时间。这项研究进行了两年的时间，并检查了四种商业杀虫剂的功效和残留效果，包括λ-氯氟氰菊酯（拟除虫菊酯），乙酰磷酸盐（有机磷酸盐），吡虫啉（新烟碱），和磺胺（磺胺）。通过在每个季节的四个不同日期在棉田上使用三种不同的浓度（高：最高标记的商业剂量（CD），介质：CD的1/10，低：CD的1/100）在田间棉田上。从各处理小区和对照0-中随机抽取4组棉花叶,2-,4-,7-,和治疗后9天（DPT），并暴露于TPB成人的实验室菌落。2016年期间，从高浓度地块中随机收集了一个额外的叶片样品/地块/喷雾/DPT间隔（0-2-4-7-9-11），并送往密西西比州化学实验室进行残留分析。TPB成虫的死亡率最高，分别在2016年和2017年的高浓度叶片0-DPT暴露（DAE）后1天，喷洒有机磷杀虫剂的叶片上死亡率（％）为81.7±23.4和63.3±28.8（SE），每年达到94.5±9.5和95.4±7.66-DAE。所有杀虫剂的死亡率持续到高和中浓度的9和4-DPT，分别。然而,在高浓度的9-DPT叶片上，有机磷（39.4±28.6）和拟除虫菊酯（24.4±9.9）的死亡率高于磺胺（10.6±6.6）和新烟碱（4.0±1.5）7-DAE。根据我们使用当前分析程序的结果，与全身性杀虫剂相比，TPB成年人对接触的敏感性明显更高，并且由于其残留作用，有机磷酸酯可以杀死超过80％的TPB群体7-DPT。
