烯啶虫胺等13种杀虫剂对褐飞虱的室内毒力测定与评价

采用稻苗浸渍法测定了烯啶虫胺等13种药剂对褐飞虱的室内毒力。结果表明,属于超高效的杀虫剂有烯啶虫胺、氟虫腈、噻嗪酮,对3龄若虫5d的LC50分别为0.13、0.19、0.29mg/L;属于高效的药剂有吡虫啉、氯噻啉、阿维菌素、甲维盐、高效氯氰菊酯、高效氯氟氰菊酯、二嗪磷,对3龄若虫的LC50介于1～10mg/L之间;属于有效的药剂有毒死蜱、异丙威、吡蚜酮,对3龄若虫5d的LC50分别为14.68、22.13、28.07mg/L。根据药剂类型、作用方式、作用机制等,建议防治稻飞虱时首选烯啶虫胺、噻嗪酮、吡蚜酮等药剂。     

异丙威、噻嗪酮及其复配对稻褐飞虱若虫的毒力测定

在室内恒温条件下,采用乙醚半麻醉点滴法测定了异丙威,噻嗪酮及其复配对稻褐飞虱４龄若虫的毒力。用Ｈｏｒｓｆａｌｌ的毒力试验设计和Ｓｕｎ的共毒系数法评价了２种药剂的联合作用。结果表明,异丙威与噻嗪酮混用,其ＬＣ５０剂量异丙威与噻嗪酮比例,除６：４和１：１两个配比外,其余配比均有显著的增效作用。其中以ＬＣ５０剂量１：９配比增效作用最大,毒性比率达２．０８,共毒系数达２４６．８６。     

烯啶虫胺对稻飞虱室内毒力测定及田间药效评价试验

采用稻茎浸渍法测定了烯啶虫胺对广州市本地稻飞虱(褐飞虱和白背飞虱)3龄若虫的毒力,结果表明:烯啶虫胺对褐飞虱和白背飞虱的LC50值分别为0.613 mg/L和0.891 mg/L。2010年和2011年田间试验结果表明:10%烯啶虫胺水剂对稻飞虱具有较好的防治效果,当用药量为45g/hm2时,药后3 d防治效果分别为84.28%和82.50%,药后7 d的防治效果分别为86.80%和87.60%。     

环氧虫啶对褐飞虱毒力的温度效应

采用室内喷雾法测定了环氧虫啶对褐飞虱杀虫活性的温度效应。结果表明:在20℃、25℃和30℃条件下,环氧虫啶的LC50分别为0.425 mg/L、0.171 mg/L和0.022 mg/L,环氧虫啶对褐飞虱的活性随温度的升高而升高,为正温度系数农药。环氧虫啶在30℃时的毒力为20℃时的19.32倍。     

氟啶虫胺腈对褐飞虱的田间防治效果

[目的]明确240g/L氟啶虫胺腈悬浮剂对褐飞虱的田间控制作用及最佳使用剂量。[方法]采用田间喷雾法,对氟啶虫胺腈37.5、50、75、100 ga.i./hm2四种不同剂量处理防治褐飞虱效果进行试验研究。[结果]240 g/L氟啶虫胺腈悬浮剂37.5、50ga.i./hm2两种剂量处理,药后1~3 d对褐飞虱的防效为51.42%~68.51%,药后7~14 d的防效为61.00%~79.10%,与对照药剂25%噻嗪酮可湿性粉剂112.5ga.i./hm2剂量处理相比,速效性相当,但持效性差;而75、100ga.i./hm2两种剂量处理,药后1~3 d防效为67.18%~74.11%,药后7~14 d防效为81.26%~89.22%,与对照药剂25%噻嗪酮可湿性粉剂112.5ga.i./hm2剂量处理相比,速效性更好,而持效性相当。[结论]240 g/L氟啶虫胺腈悬浮剂75~100 ga.i./hm2剂量喷雾处理,能有效控制褐飞虱的发生为害,可供生产上推广应用。     

三氟苯嘧啶与烯啶虫胺复配对褐飞虱防效

[目的]探索三氟苯嘧啶与烯啶虫胺2者复配的合理性及2者复配后对褐飞虱的防效.[方法]依据杀虫剂室内活性测定标准,通过室内生物活性测定和田间防效试验进行测定.[结果]三氟苯嘧啶与烯啶虫胺之间联合作用表现为增效作用,最佳比例为1:6.此比例下三氟苯嘧啶、烯啶虫胺复配制剂20 g/667m2对褐飞虱有较好的防效,施药后7 d...     

噻嗪酮与甲胺磷混用防治褐飞虱

褐飞虱是我国水稻上主要害虫之一。八十年代以来,褐飞虱的化学防治主要依赖有机磷和氨基甲酸酯类的少数品种,由于使用时间长,药效逐年下降,国内已有抗药性的报道。噻嗪酮是一种高效低毒的新型几丁质合成抑制剂,它的应用,使水稻褐飞虱的危害得到了有效的控制。但存在着杀虫谱单一,作用效果慢等弱点。为扩大噻嗪酮的杀虫谱,延缓老品种农药的使用年限,作者就其和甲胺磷的复配混用进行了有关研究。     

新型药剂烯啶虫胺防治灰飞虱试验初报

本地前期一、二、三代灰飞虱主要传播以条纹叶枯病为主的病毒病,后期五、六代灰飞虱导致植株尤其是穗部煤污发黑。试验表明,烯啶虫胺单用防治灰飞虱一代成虫、三代若虫效果较好;有效剂量相同的烯啶虫胺可溶粒剂防效略优于可溶液剂;烯啶虫胺在干旱无水的麦田使用,药效不能完全发挥,对灰飞虱的杀伤力不强。     

10%烯啶虫胺AS对柑橘粉虱室内毒力测定和田间药效试验

[目的]探明烯啶虫胺对柑橘粉虱的毒力和防治效果。[方法]采用药膜法测定烯啶虫胺对柑橘粉虱室内毒力,在田间进行小区药效试验。[结果]烯啶虫胺对柑橘粉虱成虫的LC50值为1.89 mg/kg;田间药效试验中,10%烯啶虫胺AS 100 mg/L对柑橘粉虱药后1、3 d防效分别为98.75%、96.04%。[结论]烯啶虫胺对柑橘粉虱有较高的活性和较好的防治效果。     

烯啶虫胺和噻嗪酮混剂的液相色谱分析方法研究

采用反相高效液相色谱法对30%烯啶·噻嗪酮悬浮剂中烯啶虫胺和噻嗪酮进行定量测定。结果表明,该方法中烯啶虫胺和噻嗪酮的变异系数分别为0.31%和0.09%,标准偏差分别为0.019和0.022,平均回收率分别为99.7%和100.3%,线性相关系数分别为0.9999和0.9999。     

褐飞虱的发生及其防治

2006年，水稻褐飞虱在我国南方地区再一次大暴发。药价上涨，无特效良药等问题困扰着稻农。笔者结合实际调查，就发生情况、防治误区以及进一步的防治对策展开分析，尤其对目前市场上流行的低毒药剂吡虫啉高抗性的问题进行了一次阐述，以便为来年的科学防治做为参考。     

灰飞虱的饲养及其对4种药剂的敏感性测定

从飞虱是一种重要的传毒昆虫，室内研究表明，夏季和冬季饲养灰飞虱的最佳寄主分别是物稗草和小麦：采用稻茎浸渍法和点滴法进行的生测结果表明、吡虫啉、噻嗪酮、啶虫脒及氟虫腈4种药剂中，氟虫腈的毒力最高。氟虫腈是正温度效应杀虫剂。此外，对田间灰飞虱的药剂防治策略进行了讨论。     

Insecticidal Effects of Extracts from Two Rice Varieties to Brown Planthopper, Nilaparvata lugens

Ether extracts from a resistant rice variety, Jingxian 89, and a susceptible variety, Qidaizhan, were significantly toxic to Nilaparvata lugens adult females, causing 98% and 73.5% mortalities, respectively. The area covered honeydew droplets excreted by N. lugens adult females while feeding on Qidaizhan was 28.5-fold more than the area of those feeding on the resistant variety, Jingxian 89. The honeydew covered areas were reduced 29.7- and 8.8-fold, respectively, after feeding on plants treated with the ether extracts from both varieties. Among the fractions from each variety, fractions 9 (three sterols) from both varieties and fraction 10 (3-nitraphthalic acid) from Jingxian 89 showed significant repellent effects on the planthoppers. Further bioassays revealed that fraction 9 from extracts of both varieties at 0.02 mg/ml or higher deterred the feeding activity of the planthoppers, whereas the deterrent effects of fraction 10 from the extract of Jingxian 89 were 100- to 500-fold stronger than those of fraction 9. Fraction 10, identified as 3-nitraphthalic acid, unique in Jingxian 89, was extremely toxic to N. lugens adult females, and the LC₅₀ and LC₉₀ were 0.00045 and 0.00525 mg/ml, respectively. After extensive bioassays and analysis, we concluded that 3-nitraphthalic acid plays a key role in the resistance to N. lugens adult females.     

Bio-Efficacy of Chrysoeriol7, a Natural Chemical and Repellent,against Brown Planthopper in Rice

Brown planthopper (BPH, Nilaparvata lugens Stal.) is the most damaging rice pest affecting stable rice yields worldwide. Currently, methods for controlling BPH include breeding a BPH-resistant cultivar and using synthetic pesticides. Nevertheless, the continuous cultivation of resistant cultivars allows for the emergence of various resistant races, and the use of synthetic pesticides can induce environmental pollution as well as the emergence of unpredictable new pest species. As plants cannot migrate to other locations on their own to combat various stresses, the production of secondary metabolites allows plants to protect themselves from stress and tolerate their reproduction. Pesticides using natural products are currently being developed to prevent environmental pollution and ecosystem disturbance caused by synthetic pesticides. In this study, after BPH infection in rice, chrysoeriol7 (C7), a secondary metabolite that induces resistance against BPH, was assessed. After C7 treatment and BPH infection, relative expression levels of the flavonoid-related genes were elevated, suggesting that in plants subjected to BPH, compounds related to flavonoids, among the secondary metabolites, play an important role in inducing resistance. The plant-derived natural compound chrysoeriol7 can potentially thus be used to develop environmentally friendly pesticides. The suggested control of BPH can be effectively used to alleviate concerns regarding environmental pollution and to construct a relatively safe rice breeding environment.     

井冈霉素、烯唑醇及其混剂对稻曲病菌毒力测定

运用Horsfall毒力试验和菌丝生长抑制法分别测定井冈霉素、烯唑醇及其混剂对水稻稻曲病(Ustilaginoidea virens)毒力,并用Wadley方法评价所配混剂的增效作用。结果表明,当它们按3:1和5:1的比例混配时表现增效作用。     

吡虫啉防治褐稻虱应用技术及其对天敌的影响研究

在三代褐稻虱低龄若虫高峰期，亩用吡虫啉１６克，对水６０公斤常规喷雾，药后２天的防效为８０．８％，比噻嗪酮高２９．０％，持效期长达３０天以上。吡虫吡对稻田蜘蛛的杀伤率为２７．９％，与噻嗪酮相似；对黑肩绿盲蝽的杀伤率为８５．９％，比噻嗪酮高２７．２％，仅次于甲胺磷、毒死蜱、喹硫磷的杀伤率１００％。     

第一代鲁奇炉在褐煤加压气化中的运行状况及技术改进

介绍了国内首套自行设计利用劣质褐煤加压气化制氨工艺鲁奇炉运行的状况及出现的问题。总结了自1972年以来,第一代鲁奇炉在运行中存在的主要问题及相应的技术改造状况,并对鲁奇炉运行存在的问题及发展方向进行了分析和展望。