Control of insect pests using trunk injection in a newly established apple orchard

We evaluated the potential for using preplant trunk injections of emamectin benzoate in nonbearing apple trees. Trees were evaluated for pest injury and emamectin residues throughout the planting season and into the following year. Injections into the trunk best delivered emamectin benzoate to the canopy compared with injections into the taproot, and the higher rate reduced insect pests more than the lower rate. In the following year, differences in insect control between trunk and root injections were less pronounced, but the higher rate of emamectin benzoate persisted longer and better reduced pests relative to the other treatments.     

Bio-efficacy of denatonium benzoate added formulation of bromadiolone against commensal rodents

Present day rodent management technology mostly relies on use of rodenticides, which is unsafe for human beings and other non-targets. Denatonium benzoate (DB) is an intensely bitter and non-toxic substance which is detectable by humans at a concentration of 10 ppb. Denatonium benzoate added wax block formulation of bromadiolone (0.005%) (an anticoagulant rodenticide) was evaluated against commensal rodents (house rat, Rattus rattus and lesser bandicoot rat, Bandicota bengalensis), which are always found in the proximity of pets, domestic animals and human beings. Single day exposure to bromadiolone (0.005%) formulation with DB and without DB in no-choice tests yielded 100% mortality in both the test rodent species in 2–11 days. The amount of poison bait ingested by R. rattus and B. bengalensis for both the formulations did not differ significantly, ranging between 5.87 - 7.30 and 6.51–6.71 g/100 g body weight, respectively. In choice tests in the presence of alternate plain food (broken wheat grain), consumption of both the formulations of bromadiolone (0.005%) (with and without DB) was similar to plain food at both the exposure periods (1 and 2 days), indicating a good acceptability of test rodenticide. However, mortality with a single day exposure to bromadiolone (0.005%) formulation with DB was 70% and without DB was 60–80% in both test rodent species within 3–14 days. With a two days exposure period, mortality was 100% in both the species of test rodents in 3–13 days. Single day choice test between the formulations revealed that intake of baits of both formulations by both the test rodents was similar i.e., in the range of 8.16–8.94 g/100 g b wt (bromadiolone with DB) and 8.20–9.5 g/100 g b wt (bromadiolone without DB) indicating that incorporation of a bittering agent (DB) with bromadiolone did not alter the consumption of poison in both the test species. In field trials the mean control success as assessed by census baiting and trapping methods with the application of bromadiolone (0.005%) with DB ranged between 54.0% (houses and shops) to 68.4% (poultry farms) and was 55.6% (houses and shops) to 68.4% (poultry farms) in treatments with bromadiolone (0.005%) without DB. It can be concluded that denatonium benzoate could be a best additive in rodenticidal formulations as the acceptability, palatability and toxicity in the laboratory and also its performance in field in managing the pest rodents were not altered.     

甲氨基阿维菌素苯甲酸盐对3种鳞翅目害虫与赤眼蜂的毒力

摘 要：为明确甲氨基阿维菌素苯甲酸盐对甘肃河西地区3种玉米害虫和松毛虫赤眼蜂的毒力，协调甘肃河西地区化学防治和生物防治之间的矛盾，本研究在室内采用饲喂法和药膜法分别对棉铃虫、亚洲玉米螟、粘虫和松毛虫赤眼蜂进行毒力测定。结果表明，随着甲氨基阿维菌素苯甲酸盐浓度增加，4种昆虫的校正死亡率均呈递增趋势，当药剂浓度达0.500 mg/L时，4种昆虫的校正死亡率均达95%以上。致死中浓度表明，甲氨基阿维菌素苯甲酸盐对松毛虫赤眼蜂毒力最高，致死中浓度LC50为0.078 mg/L，其次依次为亚洲玉米螟、棉铃虫和粘虫，致死中浓度LC50依次为0.109、0.120、0.127 mg/L。甲氨基阿维菌素苯甲酸盐对松毛虫赤眼蜂的毒力是其他3种鳞翅目昆虫的1.40~1.63倍。因此，综合防治中使用甲氨基阿维菌素苯甲酸盐防治害虫时，应避开赤眼蜂的出蜂时期，以降低化学杀虫剂对赤眼蜂的杀伤作用。     

甲氨阿维·虫酰肼混剂对不同蔬菜甜菜夜蛾的控制作用研究

田间小区试验结果表明,5.1%甲氨阿维·虫酰肼可湿性粉剂对番茄和白菜地的甜菜夜蛾均有较好的防治效果。在番茄地甜菜夜蛾卵孵化期施药,850~2000倍液,药后3d的防效最高,达74.92%~94.96%,药后7d已有新的幼虫孵化,防效开始下降;在白菜地甜菜夜蛾不同虫龄混发期施药,药后5d的防效最高,为83.85%~95.52%。对菜青虫有很好的兼治作用,而且对番茄和白菜安全。可以作为防治甜菜夜蛾的有效药剂推广使用,推荐使用浓度为850~1200倍。     

甲氨基阿维菌素苯甲酸盐亚致死剂量对不同敏感性棉铃虫解毒酶活性的影响

室内用甲维盐对棉铃虫选育20代,获得敏感性降低2.32倍的汰选种群(RP20)。分别采用甲维盐对同源对照种群(CP)和RP20的亚致死浓度LC25对应处理两种群的3龄初幼虫48 h,测定试虫在3~6龄不同龄期内羧酸酯酶(CarE)和谷胱甘肽S 转移酶(GST)活性,分析酶活性变化动态。结果表明,(1)两种群(CP和RP20)均随龄期的增长,CarE比活力显著增大,而GST比活力先降低后趋于稳定。(2)CK处理下,RP20与CP相比,CarE比活力在3~6龄均增大且4~6龄差异显著,而GST比活力变化较小,仅3龄和6龄显著增大。(3)与CK处理相比,甲维盐LC25处理,两种群各龄期CarE比活力均增大,且CP试虫在4龄、6龄GST比活力显著增大,在3龄、5龄无显著差异,而RP20的3龄幼虫体内GST比活力被显著抑制,在4~6龄GST比活力无明显变化。初步判断,棉铃虫对甲维盐敏感性降低与CarE比活力增大有关;甲维盐亚致死剂量对棉铃虫CarE活性具有一定的诱导作用。     

Effects of different additives on fermentation quality and aerobic stability of Leymus chinensis silage

This study investigated the effects of different additives on fermentation quality and aerobic stability of Leymus chinensis silage. Treatments included (i) no additive, (ii) 3 mL kg^?1 formic acid (FA), (iii) 6 mL kg^?1 FA, (iv) 5 mL kg^?1 acetic acid (AA), (v) 10 mL kg^?1 AA, (vi) 2 mL kg^?1 propionic acid (PA), (vii) 4 mL kg^?1 PA, (viii) 5 mL kg^?1 butyric acid (BA), (ix) 10 mL kg^?1 BA, (x) 1.0 g kg^?1 potassium sorbate (PS), (xi) 1.0 g kg^?1 sodium benzoate (SB), (xii) 1 × 10⁸ colony‐forming units (cfu) kg^?1 Lactobacillus (Lb) plantarum LP (LP), (xiii) 1 × 10⁸ cfu kg^?1 Lb. brevis LB (LB) and (xiv) 1 × 10⁸ cfu kg^?1 Lb. buchneri NCIMB40788 (Fresh). Each additive treatment was based on fresh matter (FM). Results showed that all additives decreased pH values. All additives except Fresh decreased ammonia‐N content (p < .001). Both LP and LB increased lactic acid content (p < .001). Butyric acid content increased with FA (3 mL kg^?1) and BA, but decreased with PA, PS, SB, FA (6 mL kg^?1), AA, LP, LB (p < .001). FA (3 mL kg^?1), AA (10 mL kg^?1), PA, BA, PS, SB and Fresh improved aerobic stability (p < .001). After 8 days exposure to air, the pH value and yeast count were lower in FA (3 mL kg^?1), BA (10 mL kg^?1), SB treatments than in other treatments. Overall, AA outperformed all other additives in improving fermentation quality. Sodium benzoate and AA could be used as an effective additive to improve aerobic stability of L. chinensis silage.     

杀灭松材线虫的高效药物筛选与毒性测定

为筛选出对松材线虫Bursaphelenchus xylophilus具有高效快速杀灭作用的药物,采用线虫悬浮液 + 农药的直接触杀法,选择了22种药物处理松材线虫1 h,测定了对松材线虫的半致死浓度（LC₅₀）。结果表明：不同药物对松材线虫表现出不同的杀灭作用,供试的22种药物中,甲基阿维菌素（甲维盐）杀灭效果最好,1 h 半致死浓度仅为0.3 mg·L^－1;杀螟丹效果最差,1 h 半致死浓度达21 053 mg·L^－1。另外,苦参碱、抑太保、溴氰菊酯和阿维菌素等4种药物对松材线虫具有很强的毒杀作用,其1 h半致死浓度分别为1.2,2.5,4.2和4.5 mg·L^－1。甲维盐和阿维菌素能高效快速杀灭松材线虫;这些对松材线虫高效敏感药物的筛选成功,为开发树干注射剂防治松材线虫病提供了基础。图1表3参25     

4%高氯·甲维盐微乳剂防治甜菜夜蛾田间药效试验研究

[目的]明确4%高氯.甲维盐微乳剂对甜菜夜蛾的田间防治效果。[方法]在苞菜田中,于甜菜夜蛾发生初期,按照不同施药量兑水进行叶面喷雾,计算各处理防效。[结果]该药剂有效成分用量21~27 g/hm2,药后2 d防效为91%~99%,药后5 d防效为92%~99%,药后10天防效为92%~98%,显著优于对照药剂4.5%高效氯氰菊酯乳油和1%甲氨基阿维菌素苯甲酸盐乳油。[结论]该药剂速效性好,持效性显著,可作为防治十字花科蔬菜甜菜夜蛾的有效药剂和替代乳油的环保剂型进行推广使用,推荐用药量为有效成分用量24~27 g/hm2。     

棉铃虫对甲氨基阿维菌素苯甲酸盐的抗性遗传力

 为了评估棉铃虫对甲氨基阿维菌素苯甲酸盐的抗性风险,在室内进行了棉铃虫对该药剂的抗性选育和现实遗传力分析。连续用甲维盐对棉铃虫选育25代,与同源对照种群相比,获得抗性倍数为2.974倍的汰选种群。采用阈性状分析方法,获得棉铃虫对甲维盐的抗性现实遗传力 (h²)为0.05218。进一步预测其抗性发展速度,假设以90%致死率继代处理棉铃虫,其抗性达到5倍、10倍分别需要18.67代和26.71代。