吡喹酮脂质体对实验动物的毒性作用研究

为探明吡喹酮脂质体对实验动物是否具有毒性作用,分别进行了急性和亚急性毒性试验,肝功能及血常规检查,结果表明,吡喹酮脂质体对小白鼠的半数致死量（ＬＤ５０）为腹腔注射１８６５ｍｇ／ｋｇ,分别以１／２０和１／１０ＬＤ５０的剂量隔天给小白鼠腹腔注射,连续试验７０ｄ,均无临床病理变化,给供试兔耳静脉注射该制剂１０ｍｇ／ｋｇ,给药后１－５ｄ的肝功能和血液生理生化指标同给药前相比均无显著差异。     

Aluminum,manganese, and iron tolerance improves performance of wheat genotypes in waterlogged acidic soils

Waterlogging results in high shoot concentrations of iron (Fe), aluminum (Al), and manganese (Mn) in wheat grown in acidic soil. The verification of this observation in several acidic soils, development of screening techniques, and identification of genotypes differing in tolerance made it possible to test whether tolerance of ion toxicities improves performance of wheat in waterlogged acid soils. Six wheat varieties selected for tolerance/intolerance of Al, Mn, and Fe were grown in three acidic soils (pH_CaCl2 4.1–4.3) with or without waterlogging for 40 d. In terms of relative shoot dry weight, Al‐, Mn‐, and Fe‐tolerant genotypes tolerated waterlogging better, outperforming intolerant genotypes by 35%, 53%, and 32%, respectively, across the soils. The Al‐tolerant genotype had up to 1.8‐fold better root growth than the intolerant genotype under waterlogging. Waterlogging increased DTPA‐extractable soil Mn (71%) and Fe (89%), and increased shoot Fe (up to 7.6‐fold) and Al (up to 5.9‐fold) for different genotypes and soils. The Al‐tolerant genotype maintained lower tissue concentrations of Al as compared to intolerant genotypes during waterlogging. Waterlogging delayed crop development but distinctly less so in the tolerant than in the intolerant genotypes, thus jeopardizing the capacity of intolerant genotypes to produce yield in Mediterranean climates with dry finish of the season. Pyramiding multiple ion tolerances into current wheat varieties with desirable agronomic and quality characteristics to enhance their performance under waterlogged acid soils should be considered.     

农药对稻田捕食性天敌泽蛙的安全性研究

1981～1989年用百余种农药对稻田害虫天敌泽蛙(Rana limnocharis)的蝌蚪、幼蛙和成蛙进行了毒性测定和田间试验,发现杀虫剂的安全性比杀菌剂、除草剂要小.从药量安全指数和48h 的LC_(50)值来看,杀虫剂中拟除虫菊酯类、有机氯类以及沙蚕毒素、杀虫环、杀螟丹、嘧啶硫磷、治螟磷、百菌清、菲醌、苏化911、五氯酚钠、毒草安等品种安全性小.乳油剂的安全性比可湿性粉剂小.混合制剂及不同作用机制的药剂混配安全性变小.泽蛙对农药敏感,尤以蝌蚪最敏感.农药对泽蛙蝌蚪急性毒性可分3类,室内48h LC_(50)值小于1ppm,田间48h 药量安全指数小于0.5时,为高毒类;室内LC_(50)为1～10ppm,田间48h 药量安全指数为0.5～2.5时,为中毒类;室内LC_(50)大于10ppm,田间48h 药量安全指数大于2.5时,为低毒类.     

19种杀菌剂对黑皮冬瓜疫病病菌室内毒力测定

为筛选防治黑皮冬瓜疫病的高效药剂,进行19种常见商品杀菌剂对黑皮冬瓜疫病病菌的室内毒力测定,结果表明,50%安克可湿性粉剂和50%施得益可湿性粉剂的毒力最强,对黑皮冬瓜疫病病原菌的生长抑制率分别为89.36%和87.43%,其余为72%克露可溶性粉剂53.07%、68%金雷多米尔水分散粒剂51.43%,这几种杀菌剂可直接在生产中使用。     

A survey of element toxicities in wheat grown in naturally waterlogged farmer's sodic fields of eastern Uttar Pradesh,India

This survey examined the element toxicities in wheat grown in naturally waterlogged farmer's sodic fields. Seven sites located in three districts (Faizabad, Pratapgarh, and Ambedkar Nagar) of eastern Uttar Pradesh, India were selected for the study. The data on soil redox potential (Eh), soil pH, soil electrical conductivity (EC), waterlogging duration, and crop age during waterlogging were recorded at the time of plant sampling in all the sites. Waterlogging caused a reduction of 21% to 65% in shoot dry weight in the survey sites. During waterlogging, the concentrations of iron (Fe), aluminum (Al), and sodium (Na) in leaves increased dramatically; the values of these elements were many folds higher than their reported critical toxicity levels (Fe-100 ppm, Al-50 ppm, and Na-8000 ppm, respectively). The results support the hypothesis that element toxicities occur during waterlogging in wheat grown in farmer's sodic field and identified Fe, Al, and Na toxicities as a major constraint for wheat production in the study area.     

102中草药复方制剂的毒性试验

采用灌胃和腹腔注射的方法,对１０２中草药复方制剂进行了急性毒性试验和亚急性毒性试验,结果表明,该制剂水提物给小白鼠灌胃,其毒副作用很小,耐受量大于１ｍＬ／１０ｇ,４５ｄ后,小白鼠体重明显增加,与对照组相比差异显著,心、肝、脾、胃、肾作组织学检查,未民两全是变化,给小白鼠腹腔注射,该制剂有毒性,ＬＤ５０为０．５４５ｍｌ／１０ｇ,故该制剂水提物不宜腹腔注射给药。     

两种杀虫剂对甘蓝蚜的毒力测定及室内药效试验

 在室内用氯氰菊酯、敌敌畏分别对甘蓝蚜［Brevicoryne brassicae(Linnaeus)］进行了毒力测定及防治试验。结果表明:氯氰菊酯和敌敌畏乳油对甘蓝蚜的ＬC₅₀分别为4.113 7,116.486 1 μg/mL,10%氯氰菊酯和80%敌敌畏乳油分别稀释成1 500～3 000倍液和1 500倍液对甘蓝蚜的室内防治效果较好,其药后第1～5 d的防效分别为75.3%～87.4%和76.7%～86.6%.     

9种杀虫剂对绿盲蝽的毒力效果比较

【目的】 研究不同杀虫剂对新疆阿克苏地区绿盲蝽的毒力效果,为绿盲蝽防控提供科学依据。【方法】 采用玻璃管药膜法,比较9种杀虫剂对阿克苏地区绿盲蝽成虫的毒力效果。【结果】 9种杀虫剂对绿盲蝽成虫的毒力作用均随着药剂浓度的升高而增强,其对绿盲蝽成虫的毒力效果从高到低的顺序依次为丁硫克百威>毒死蜱>呋虫胺>氟啶虫胺腈>高效氯氟氰菊酯>啶虫脒>吡虫啉>噻虫嗪>阿维菌素;阿克苏地区不同采样点绿盲蝽种群对药剂的敏感性水平不同。【结论】 在棉花花蕾期,可选用丁硫克百威、氟啶虫胺腈、呋虫胺作为目前防治该虫用的啶虫脒与高效氯氟氰菊酯等常规农药的替代药剂轮换使用,有效控制绿盲蝽发生和危害。     

Bt转基因棉花抗棉铃虫毒性机理研究

应用江苏省农业科学院经济作物研究所提供的Ｂｔ转基因棉花（编号８８４０），经盆栽、田间反复鉴定对棉铃虫１龄幼虫抗虫效果平均为９３．１％，叶、蕾、铃饲喂３龄幼虫抗虫效果分别为９０％、８５％、５５％测定毒性机理。棉铃虫３龄幼虫取食抗虫棉２ｄ后，其食量、排泄量分别比该材料未导入Ｂｔ转基因对照植株减少５７．１０％，５７．１９％；幼虫长度、体重增长率分别比对照减少７１．６９％、８１．５１％。４ｄ后食量、排泄量减少７２．０２％、７７．３３％，体长和体重增长率分别比对照减少９３．０２％、１０７．７９％。测定中肠、血清ｐＨ值分别为８．１９和６．４，与对照８．３６、６．５差异不大。中肠超微结构观察，取食抗虫棉中毒死亡的棉铃虫幼虫中肠横纹肌呈收缩状；表明中肠处于中毒痉挛状态，吸收营养物质的柱状细胞微绒毛萎缩并局部被破坏，肠壁细胞质内的细胞器减少。营养物质自耗成空胞。而取食对照植株幼虫中肠超微结构则相反，肌肉舒畅。微绒毛多而正常，细胞器丰富，幼虫生长发育正常。