近年新开发的农药品种

介绍了近年来新开发的14个农药品种,其中indaziflam等6个产品为除草剂,ametoctradin等6个产品为杀菌剂,sulfoxaflor和fluensulfone为杀虫剂。     

Fenvalerate residue level and dissipation in tea and in its infusion

Fenvalerate is a non-systemic insecticide/acaricide used in controlling a wide range of pests, including those resistant to organochlorine, organophosphorus and carbamate insecticides. The study investigated the dissipation behaviour (residue level) of fenvalerate in tea and its transfer during infusion. Fenvalerate was applied on tea crop at two dosages, 100 and 200?g a.i.?ha^?1 (recommended and double the recommended) in the dry and wet seasons under field conditions. Samples (green tea shoots, made tea, its infusion and spent leaves) were analysed for fenvalerate by high-performance liquid chromatography using diode array detection. The residue dissipated faster in the wet season than in the dry season. Seven days after the treatment (normal round of plucking) the residues observed in the green shoots at the two dosages were 0.5?±?0.01, 1.1?±?0.01 and 0.4?±?0.02, 0.9?±?0.01?mg?kg^?1 in the dry and wet seasons, respectively. During processing of green tea shoots to made tea a 30–40% loss of residue was observed. The transfer of residue from made tea to infusion was in the range 10–30% for both seasons, whereas 50–70% of the residues remained in the spent leaves. However, the degradation rate in both seasons followed first-order kinetics. The half-lives were in the range of 2–3 days for green shoots and made tea in both seasons.     

99种植物提取物对玉米象的生物活性测定

为发现新的植物源储粮害虫防控剂,以玉米象(Sitophilus zeamais)为试虫,采用饲料混药法,对50科99种植物样品进行了室内活性筛选.结果表明,在0.013 g DW/g小麦的剂量处理下,百部(Stemona sessilifolia)等24种植物提取物表现出较好的毒杀活性和种群抑制作用,15 d的死亡率或64d的种群抑制率高于80％,其中栓翅卫矛(Euonymus phellomanus)、使君子(Quisqualis indica)、射干(Belamcanda chinensis)和黄芩(Scutellaria baicalensis)的种群抑制率均高达100％;天名精(Carpesium abrotanoides)、百部、狼毒、使君子和栓翅卫矛等5种植物提取物对玉米象还具有一定的触杀作用.测定结果初步表明,天名精、使君子、百部、狼毒、射干、黄芩和栓翅卫矛等7种植物有进一步研究价值.     

8个烟碱类杀虫剂生物活性比较研究

比较吡虫啉、啶虫脒、烯啶虫胺、噻虫啉、噻虫嗪、噻虫胺、氯噻啉、呋虫胺等8个烟碱类杀虫剂的生物活性,为科学应用提供参考。采用浸渍法、浸稻苗法、浸叶碟法等对豆蚜、褐飞虱、二化螟、小菜蛾进行室内毒力测定,对活性进行分组,并进行了结构与活性关系初步分析。结果表明:烟碱类药剂对豆蚜LC50值为0.0314⁰.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 70.3505 mg/L,对抗吡虫啉的褐飞虱LC50值为0.565 7⁴9.404 6 mg/L,对二化螟LC50值为7.517649.404 6 mg/L,对二化螟LC50值为7.5176¹39.0369 mg/L,对小菜蛾LC50值为10.533 4139.0369 mg/L,对小菜蛾LC50值为10.533 4¹00 mg/L。烟碱基闭环与开环、取代杂环等结构特点对药剂活性有影响。烟碱类药剂对同翅目害虫的活性显著优于对鳞翅目害虫的活性。在实际应用中可以采取轮用策略和兼治策略推进药剂的科学合理使用,还可加强研发种子处理剂等。     

反相高效液相色谱法分析锐劲特

利用反相高效液相色谱外标法测定了锐劲特的含量,方法的标准偏差为０．０５２,变异系数为０．９４％,平均回收率９９．９％。     

嘧啶磷的合成研究

研究了以石灰氮为原料合成中间体 2 二乙基氨基 6 甲基 4羟基嘧啶 (简称嘧啶醇 ) ,并在催化剂存在下反应合成乙基嘧啶磷的方法。产品纯度 92 .3% ,收率 73.2 %。     

杀虫剂呋线威的合成

介绍了以SCl2 为氯化剂 ,直接合成呋线威的方法。该法具有合成路线短 ,收率高 ,反应温和的特点。     

高效杀虫剂吡蚜酮的合成

研究了乙酸乙酯法合成中间体 2 ,3,4 ,5 四氢 3 氧 4 氨基 6 甲基 1 ,2 ,4 三嗪 (以下简称氨基三嗪酮 ) ,3 氰基吡啶法合成吡蚜酮。中间体合成收率 60 .4 % ,产品合成收率 93.1 % ,产品纯度 96.7%。     

HPLC flavonoid profiles as markers for the botanical origin of European unifloral honeys

The HPLC phenolic profiles of 52 selected unifloral honey samples produced in Europe were analysed to detect possible markers for the floral origin of the different honeys. Lime‐tree (five markers), chestnut (five markers), rapeseed (one marker), eucalyptus (six markers) and heather (three markers) honeys had specific markers with characteristic UV spectra. In addition, the flavanone hesperetin was confirmed as a marker for citrus honey, as well as kaempferol for rosemary honey and quercetin for sunflower honey. Abscisic acid, which had been reported to be a possible marker for heather honey, was also detected in rapeseed, lime‐tree and acacia honeys. Ellagic acid in heather honey and the hydroxycinnamates caffeic, p‐coumaric and ferulic acids in chestnut, sunflower, lavender and acacia honeys were also detected. The characteristic propolis‐derived flavonoids pinocembrin, pinobanksin and chrysin were present in most samples in variable amounts. © 2001 Society of Chemical Industry