Laboratory and field evaluation of <Emphasis Type="Italic">Beauveria bassiana</Emphasis> for controlling Mulberry whitefly <Emphasis Type="Italic">Pealius mori</Emphasis> Takahashi (Homoptera: Aleyrodidae) in mulberry (<Emphasis Type="Italic">Morus alba</Emphasis> Linn)

In a laboratory screening of 12 isolates of entomopathogenic fungi against nymphs of the mulberry whitefly (Pealius mori Takahashi), Beauveria bassiana (Balsamo-Crivelli) Vuillemin CKB-048 was the most virulent, causing 87 ± 3% mortality at 1 × 10⁶ conidia/ml. Infection was confirmed by growth of the fungus from cadavers and by scanning electron microscopy of treated nymphs. Beauveria bassiana CKB-048 was formulated as a wettable powder (1 × 10⁹ conidia/g) and tested in two mulberry (Morus alba Linn) plantations in central and northeastern Thailand. In both locations, two spray applications of B. bassiana CKB-048 at 3.75 × 10¹² to 6.25 × 10¹² conidia/ha and at 14 day intervals provided good control of whitefly nymphs; control with B. bassiana CKB-048 was comparable to that with the pesticide buprofezin at 250 g of active ingredient/ha. In addition, no mortality of silkworm larvae occurred when the larvae were fed with mulberry leaves sprayed with B. bassiana CKB-048 7, 14, or 21 days earlier.     

70%烯啶虫胺·噻嗪酮水分散粒剂的研制

[目的]介绍70%烯啶虫胺.噻嗪酮水分散粒剂的配制方法、产品性能及防治效果。[方法]选择聚羧酸盐和脂肪醇磺酸盐作为润湿分散剂（分别为3%和13%）、尿素为助崩解剂（5%）、聚乙烯醇、聚乙二醇为黏结剂（1.5%～2.5%）和绢云母粉为填料,采用干式挤压造粒工艺将烯啶虫胺和噻嗪酮原药配制成70%烯啶虫胺.噻嗪酮水分散粒剂,并测定产品性能及田间防治效果。[结果]该产品分散性好,悬浮率大于90%,润湿时间小于30 s,崩解时间小于60 s,（54±2）℃14 d的热贮分解率小于5%,各项指标均符合水分散粒剂的要求。田间试验表明,该药剂防治水稻褐飞虱药后3、7和14 d的防效分别为91.40%、95.14%和95.76%,明显高于烯啶虫胺和噻嗪酮单独施用的防治效果。[结论]该药剂是防治水稻稻飞虱的理想药剂。     

Buprofezin toxication implicates health hazards in Nile tilapia (Oreochromis niloticus)

The objective of this study was to investigate the toxic effects of buprofezin insecticide on Nile tilapia (Oreochromis niloticus). The fish were exposed to buprofezin at 100 mg/L for 28 days. Compared to control, activity of serum transferases and levels of urea and creatinine showed significant increases. Oxidative stress was recorded manifested by elevated levels of malondialdehyde (MDA), reduced concentrations of reduced glutathione (GSH) and inhibition of activities of superoxide dismutase (SOD) and catalase (CAT) in liver and kidney. Examination of peripheral RBCs revealed elevated frequency of micronucleated cell. Interleukin 1 beta (IL‐1β) gene was upregulated in liver, muscle and brain, while that of cyclooxygenase 2 (COX‐2) gene increased in liver and muscle, but not in brain. Histopathological alterations were recorded in liver, kidneys, brain, gills, pancreas, spleen, intestine, muscle and ovaries. The immunohistochemical detection of caspase‐3 in the liver revealed no differences between treated and control groups; however, the expression of inducible nitric oxide synthase (iNOS) was demonstrated in hepatocytes and hepatopancreas in buprofezin‐treated group compared to control. It has been concluded that the tissue damage induced by buprofezin in Nile tilapia is mediated by oxidative stress and inflammatory response but not by apoptosis.     

气相色谱法检测茶叶中噻嗪酮(优乐得)和菊酯类农药的残留量

利用配有电子捕获检测器(ECD)的气相色谱仪测定了茶叶中噻嗪酮(优乐得)、甲氰菊酯、氰戊菊酯、联苯菊酯的残留,结果4种农药的检出限量分别为0.01、0.01、0.05、0.01 mg/kg,加标回收率分别为86.0%~100.5%、84.7%~99.3%、83.3%~100.2%、87.3%~100.5%,且变异系数均在2.1%~4.6%范围内,表明该方法的准确度、灵敏度、精密度均较高。     

Studies on Stimulating Effect of Two Selective Insecticides on the Numbers of Laid Egg by Yellow Rice Borer,Tryporyza incertulas (Walker) and Their Effects on Biochemistry of Rice Plants

Buprofezin and imidacloprid are selective insecticides against Homoptera insects. This paper in-vestigated stimulating effect of the two insecticides on the number of laid eggs by yellow rice borer, Tryporyzaincertulas (Walker) of three generations in 2001 -2002. The results showed that the reproductive rate of emer-gence months during the larvae feeding on the rice plants of Xiushui63 treated with the two insecticides was sig-nificantly higher than that of control, indicating that the numbers of laid eggs by the borer was stimulated fol-lowing buprofezin and imidacloprid applications. However, there was no such effect for the larvae feeding onrice variety Zhendao2 which showed moderate resistance to the insect. In addition, the incidence of stimulatingegg laid for the first instar treated with the two insecticides was greater than that for the third instar. Bio-chemical tests showed that oxalic acid concentration declined, and photosynthetic rate of rice leaves followingthe two insecticide applications declined significantly compared to control, whereas reducing sugar concentra-tion increased significantly for all other treatments of two varieties except Xiushui63 treated with buprofezin.The level of glutathione-S-transferase varied with rice variety and insecticide.     

2种药剂防治水稻中后期褐飞虱的效果研究

[目的]了解50％呋虫胺水分散粒剂、60％吡蚜酮·噻嗪酮可湿性粉剂防治水稻褐飞虱的效果,确定其最佳使用剂量.[方法]通过田间小区药效试验研究了50％呋虫胺水分散粒剂、60％吡蚜酮·噻嗪酮可湿性粉剂对水稻中后期褐飞虱的防治效果、持效时间和最佳使用剂量.[结果]在褐飞虱卵孵化高峰期使用50％呋虫胺水分散粒剂180 g/hm2或者60％吡蚜酮·噻嗪酮可湿性粉剂600 g,/hm2,药后23 d防效可达90％以上,且对作物安全,对天敌影响较小.[结论]该2种供试药剂在水稻中后期防治3代褐飞虱有较好的持效性,可望进一步研究开发.     

噻嗪酮在水稻上的内吸输导作用和消解动态

 通过液相色谱检测结合生物活性测定与田间试验，证明水稻对噻嗪酮具有明显的内吸辅导作用。 稻茎可吸收和富集田水中的噻嗪酮，浓缩系数为2.4～3.5.施药187.5 g(ai)／ha后1～4周，噻嗪酮在稻茎中的消失率依次为73．30％、90.32％和95.01％。粗喷雾、泼浇、弥雾、毒土（有水层）等不同施药方式之间的防效差异不显著。试验表明，噻嗪酮对稻飞虱的高度生物活性，在水稻上的内吸作用和稻茎对田水中药剂的吸收、富集能力，是该药在田间表现长效的主要原因。     

Lethal and sublethal effects of buprofezin and imidacloprid on Bemisia tabaci (Hemiptera: Aleyrodidae)

The sweetpotato whitefly, Bemisia tabaci (Gennadius), has become a major threat to agriculture worldwide. The development of insecticide resistance in B. tabaci has necessitated the exploration of new management tactics. The toxicity of imidacloprid and buprofezin to various life stages of B. tabaci was determined in the laboratory. Also, the sublethal effects of both insecticides were studied on demographic and biological parameters of B. tabaci. Both insecticides were very toxic against first stage larvae of the pest with LC₅₀ values of 1.0 and 19.3 ppm for buprofezin and imidacloprid, respectively. Toxicities decreased between successive stages (LC₅₀ values ranging from 1.0 to 2854.0 ppm). The LC₅₀ values of imidacloprid for adult males, females and eggs were 11.8, 71.6 and 151.0 ppm, respectively. Buprofezin had no significant effect on adults and eggs. The sublethal concentration of imidacloprid had no significant effect on demographic and biological parameters of B. tabaci but the maximal value for the mean generation time (T) (18.8 day) was observed in imidacloprid treatment. Buprofezin significantly decreased stable population and biological parameters of B. tabaci except it did not decrease the rate of population increase or the sex ratio of offspring.     

噻嗪酮在柑橘和土壤中的残留及消解动态

[目的]监测噻嗪酮在柑橘和土壤中的残留量。[方法]采用气相色谱法测定噻嗪酮在柑橘和土壤中的残留。[结果]噻嗪酮在柑橘全果中的平均回收率为96.17%～97.38%,变异系数为6.10%～9.07%;在果肉中的平均回收率为95.24%～105.46%,变异系数为3.30%～6.01%;在果皮中的平均回收率为88.76%～93.64%,变异系数为5.12%～6.27%;在土壤中的平均回收率为97.79%～104.3%,变异系数为2.45%～9.21%。噻嗪酮在柑橘和土壤中的消解动态以及最终残留结果表明,在湖南长沙、浙江杭州和贵州贵阳3地柑橘中的消解半衰期分别为7.65、7.64、8.40 d,在土壤中的消解半衰期分别为13.75、9.97、10.18 d。[结论]在柑橘上使用25%噻嗪酮悬浮剂对水剂,按照推荐使用剂量为166.7～250.0 mg/L,施药2～3次的情况下,噻嗪酮在柑橘上的安全期可定为14 d。     

扑虱灵、蚊蝇醚对烟粉虱若虫和卵生物活性的研究

用浸叶法和浸渍法测定了扑虱灵、蚊蝇醚对以棉花为寄主饲养的烟粉虱卵和若虫的生物活性.结果表明:扑虱灵对1龄和4龄若虫毒力的LC50值分别为1.3、128.8 a.i.mg/L,浓度为100～1600 a.i.mg/L的扑虱灵对0～1日龄卵孵化几乎无抑制作用;蚊蝇醚浸叶法和浸渍法使用对0～1日龄卵毒力的LC50值分别为0....