为明确40％砜吡草唑悬浮剂土壤喷雾处理对大豆田一年生杂草的防效及对大豆的安全性,2021年采用随机区组设计进行田间药效试验.结果表明:40％砜吡草唑悬浮剂在150、180、210、360 g a.i./hm2剂量下对大豆田主要杂草马唐、狗尾草、藜、反枝苋、稗草、青葙、苘麻、马齿苋等均有较好防治效果.药后40d总草株防效88.14％～97.58％,总草鲜重防效86.44％～97.73％,增产率3.52％～12.68％,且对供试大豆品种安全.40％砜吡草唑悬浮剂可作为大豆田备选除草剂,采用土壤喷雾法防治大豆田一年生杂草,推荐使用剂量150～180 g a.i./hm2.

The indoor herbicidal activity of a new herbicide pyroxasulfone with soil spray blocking treatment against four main weeds in soybean fields, Abutilon theophrasti, Chenopodium album, Setaria viridis and Digitaria sanguinalis, was studied by using the indoor bioassay method, and evaluated the safety of pyroxasulfone against three soybean varieties. The results showed that pyroxasulfone had high biological activities on four kinds of weeds and had good safety for the three soybean varieties, the selectivity index was higher than 2. So it can be used as a soil sealing treatment agent in soybean field.

为筛选出防治黏虫的高效杀虫剂,通过喷雾法测定了溴虫氟苯双酰胺和联苯菊酯复配对黏虫的联合毒力.结果表明:溴虫氟苯双酰胺和联苯菊酯以质量比 5∶1、3∶1、1∶1、1∶3 和1∶5 复配对黏虫的共毒系数分别为122.37、141.50、102.19、114.68和 117.11.综合考虑,3∶1 为溴虫氟苯双酰胺和联苯菊酯混配的最佳配比.

作为γ-氨基丁酸门控氯离子通道别构调节剂,溴虫氟苯双酰胺(Broflanilide)是目前唯一获得登记的双酰胺类杀虫剂,它不仅具有广谱、高效等活性特点,且能有效防治抗性害虫.为获得结构多样性新型双酰酰胺类杀虫活性化合物,对溴虫氟苯双酰胺进行先导结构多样性衍生,设计合成了系列新型双酰胺类化合物,其结构经1H NMR和MS等表征确证.研究结果表明,该类化合物对粘虫等鳞翅目害虫和蚜虫等半翅目害虫均具有高活性,对害螨棉红蜘蛛也具有显著活性.

为明确湖南草地贪夜蛾对甲氨基阿维菌素苯甲酸盐、氯虫苯甲酰胺、高效氯氟氰菊酯和茚虫威等的抗药性程度,建立了田间玉米草地贪夜蛾种群的敏感基线.用浸叶法测定了四种类型杀虫剂对湖南省10个地级市的草地贪夜蛾种群3龄幼虫的LC50,并以此为毒力基线.将10个种群所测数据进行合并计算毒力回归方程,得出混合种群的敏感基线.结果表明草地贪夜蛾不同田间种群对四种类型的敏感性均存在一定差异,其中对甲氨基阿维菌素苯甲酸盐抗性最低和抗性最高的种群分别为张家界(慈利县)种群和常德(鼎城区)种群,其抗性倍数分别为4.95和2.21,最高值与最低值之间的抗性差异达到2.24倍,10地种群对四种类型的抗性倍数在1-5之间.湖南不同地区草地贪夜蛾种群对四种类型杀虫剂虽未达到低抗性水平,但敏感性已降低.

采用喷雾法研究了新型双酰胺类化合物HNPC-A102对蓟马的田间防治效果.田间药效试验结果表明:30～60 g a.i./hm2剂量下,药后1d,HNPC-A102对茄子蓟马防效达86％以上,与同等剂量对照药剂溴氰虫酰胺相当;药后8d,HNPC-A102对茄子蓟马防效达95％以上,溴氰虫酰胺防效均不足35％;药后13d,HNPC-A102对茄子蓟马仍保持89％～95％的防治效果.HNPC-A102能够有效防治蓟马,且速效性及持效性好,对作物安全,具有进一步研究开发价值.

Spodoptera frugiperd a is a major invasive alien pest with a wide range of hosts and can cause damage to a variety of crops. The feeding preferences of larvae from newly hatched to the sixth instar to seven types of crops in Hunan Province and the survival rate of the third instar larvae feeding on different plants were investigated. The results showed that S. frugiperda has an obvious oviposition and feeding preference in main crops in Hunan Province. The oviposition preferences for different crops were sorted from highest to lowest, in descending order: corn, sesame, cotton, rice, peppers,tobacco, and citrus. Feeding preference of larvae from the third to the sixth instar for main crops in Hunan were as follows,in descending order of preference: corn, rice, sesame, tobacco, citrus, cotton, and pepper. There were significant differences in the survival rates of the third instar larvae feeding on different crops, individuals feeding on maize showed the highest survival rate（98.33%） while citrus-feeding ones had the lowest survival rate（11.67%）. S. Frugiperda can complete life cycle on seven crops. We should strengthen the monitoring of S. Frugiperda on corn as well as rice in production.

自主设计、合成了系列新型邻胺基苯甲酰胺类化合物,并对其进行了杀虫活性、安全性、毒性、工艺、制剂、温室和/或田间防治效果等研究,获得了Ia、Ib和Ic等系列自主知识产权的高杀虫活性化合物.结果 表明化合物Ic等对咀嚼口器害虫如粘虫和小菜蛾等的活性较邻胺基苯甲酰胺类杀虫剂氯虫苯甲酰胺水平相当或更胜一筹,对刺吸口器害虫如蚜虫等的活性远优于氯虫苯甲酰胺及溴氰虫酰胺.田间药效试验进一步证实,Ic等对咀嚼口器害虫如水稻二化螟、稻纵卷叶螟、甜菜夜蛾等的防治效果相当于或优于氯虫苯甲酰胺,对刺吸口器害虫如蚜虫等的防治效果优于溴氰虫酰胺.新型邻胺基苯甲酰胺类化合物Ic等可作为候选杀虫剂进一步研究开发.

[目的]为了评价甲磺草胺对水生生物的毒性风险.[方法]在实验室条件下,分别以斜生栅藻、大型溞、斑马鱼、非洲爪蟾蝌蚪、小浮萍、穗状狐尾藻6种水生生物为试验对象,参照OECD测试指南和《化学农药环境安全评价试验准则》,研究了甲磺草胺对6种水生生物的毒性.[结果]甲磺草胺对斜生栅藻生长率72 h-ErC50为0.415 mg a.i./L,对斜生栅藻生物量72 h-EyC50为0.227 mg a.i/L;对大型溞48 h-EC50为21.89 mg a.i./L;对斑马鱼96 h-LC50为32.69 mg a.i/L;对非洲爪蟾蝌蚪96 h-LC50＞100 mg a.i./L;对小浮萍7d时ErC50和EyC50分别为叶状体数0.107、0.084 mg a.i./L,叶总面积0.103、0.078 mg a.i./L,鲜重0.099、0.082 mg a.i./L;对穗状狐尾藻14 d时ErC50和EyC50分别为整株长0419、0.266 mg a.i./L,整株鲜重0.521、0.330 mg a.i./L,整株干重0.508、0.322 mg a.i/L.毒性等级划分标准,甲磺草胺对斜生栅藻为高毒,对大型潘、斑马鱼、非洲爪蟾为低毒,目前暂无农药对浮萍和狐尾藻的毒性等级划分标准,参照藻类毒性等级划分,甲磺草胺对小浮萍和穗状狐尾藻为高毒.[结论]甲磺草胺对水体中的植物毒性高,在田间使用中,应避免甲磺草胺进入水体环境.