不同杀螨剂对截形叶螨的毒力测定及田间药效试验

采用室内毒力与田间试验相结合研究截形叶螨的防治,室内毒力试验表明,供试药剂浓度与死亡率存在正相关,由室内毒力测定和田间药效综合分析,在防治截形叶螨时首选20%哒螨灵Wp、57%炔螨特EC、5%阿维菌素EC、0.5%印楝素EC,7d防效高达87%以上。     

瓶鼻海豚成体骨骼系统的度量特征

文章将收藏于广州海洋馆的瓶鼻海豚（Tursiops trurncntus）标本解剖并制取骨骼标本1副,对其骨骼系统作了较为全面的测量和相关的统计分析。结果表明,瓶鼻海豚V型骨最大高、最大宽和最大厚等尺度均呈现先逐渐变大、后逐渐变小的特点;腰椎质量与体长之间存在明显的线性关系（R^2=0．9306）;尾椎质量与椎体高之间、质量与椎体长之间均存在明显的幂函数关系（R^2=0．9767,R^2=0．9407）;幂函数能很好地拟合V型骨质量与最大高之间的数学关系（R^2=0．9320）;左、右肋骨完全对称;左、右胸肋完全对称。瓶鼻海豚骨骼各椎体质量与体长之间的函数关系可能反映了各椎体的某种生长规律,如线性生长或等速生长。     

国槐截形叶螨的生物学特性及防治

北京地区国槐普遍受截形叶螨（ＴｅｔｒａｎｙｃｈｕｓｔｒｕｎｃａｔｕｓＥｈａｒａ）危害，从５月下旬至１１月上旬均有发生，危害盛期在７—８月份，有螨叶率市区达７０％，近郊区可达９０％以上。根据有效积温及气象资料推算，截形叶螨在北京地区每年发生１５—１７代。在２８℃、ＲＨ６７℃条件下，室内饲养，发育一代平均６．７天，在２７℃、Ｒｈ７２％条件下，雄成螨平均寿命７．５天，雌成螨１０．７天。截形叶螨以成螨越冬，其场所主要在树干及粗枝树皮裂缝内，极少部分在小校、树冠下草地及根际土壤中。早春用生物制剂—２．５％日光霉素１０００倍，１０％增效浏阳霉素２０００倍７３％克螨特乳油２０００倍及洗衣粉４００倍，碳酸氢铵颗粒剂１００倍防治，均能取得很好的效果。     

Formulation of vegetable fat pellets with pheromone and Beauveria bassiana to control the larger grain borer,Prostephanus truncatus (Horn)

The use of hydrogenated rapeseed oil as a carrier for conidia of the entomopathogenic fungus Beauveria bassiana (Bals) Vuill was investigated as part of a research programme on the control of the larger grain borer, Prostephanus truncatus (Horn). Melting the oil, which is solid at temperatures below 32 °C, allows the incorporation of materials such as aggregation pheromones and conidia; sudden cooling produces solid fat pellets. In attraction tests conducted with pellets containing P truncatus aggregation pheromone, significantly higher numbers of beetles were attracted to pellets containing pheromone at a concentration of 4 ml litre⁻¹ compared to control pellets for at least four weeks when held in Petri dishes in the laboratory and for at least six weeks when pellets held in insect traps were exposed to outside conditions. The attraction was retained over a period of storage in glass bottles; pellets stored in the freezer or incubator (at −10 °C or 27 °C) attracted beetles according to the pheromone level for the duration of the work (14 and 13 months respectively). When pheromones and conidia were incorporated into the same pellets they could be stored in a freezer or refrigerator retaining over 80% viability after 51 weeks; those stored in an incubator at 27 °C showed significantly lower germination at 20.7–27.2% after the same time. There was an indication that the pheromone caused a slight reduction in the viability of conidia, although this may have been just a slight delay in the speed of germination. Rapid dose transfer from pellets with conidia with and without the addition of pheromone was demonstrated. Insects were exposed to pellets for 24 hours and 96–100% mortality was observed in treatments containing conidia within six days of exposure. © 1999 Society of Chemical Industry     

Modelling dolphin distribution within an Important Marine Mammal Area in Greece to support spatial management planning

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