Photoperiodic summation is temperature-dependent inPyrrhocoris apterus (L.) (Heteroptera)

Summary InPyrrhocoris apterus, a low temperature, 15°C, prevented the termination of diapause by long days and, unexpectedly, also the induction of diapause by short days. Both responses were enabled at a higher temperature, 26°C. In contrast to current concepts, it was proved that the summation of photoperiodic signals was temperature-dependent, since the morphogenetic development was prevented by starvation.     

Cycles of juvenile hormone esterase activity during the juvenile hormone-driven cycles of oxygen consumption in pupal diapause of flesh flies

Summary During diapause O₂ consumption in fly pupae is a cyclic event (4-day periodicity at 25°C) driven by cycles of juvenile hormone activity. Levels of juvenile hormone esterase activity change systematically during the cycle, with highest activity observed at the nadir of the O₂ consumption cycle.Supported in part by grant 88-37153-3473 from the USDA Competitive Grants Office and grant 23-088 from the USDA Forest Service. Thanks to Dr Ming Tu Chang for her helpful advice.     

鞭角华扁叶蜂预蛹脂肪体和血淋巴中糖类含量动态

研究了鞭角华蜂滞育预蛹的糖类含量动态。结果表明，在滞育期间，鞭角华扁叶蜂滞有预蛹脂肪体糖原的含量呈下降趋势，血淋巴中海藻糖的含量则升高的趋势。在否育的前期，机体内糖原和海藻糖之间 存在明显的相互转化，并与滞育阶段和温度相关。雌性预蛹糖原和海藻糖的含量均高于雄性预蛹，但代谢趋势一致。     

Photoperiodically induced delayed insect metamorphosis: a larval oligopause inDiatraea saccharalis

Summary Sugarcane borers enter a state of delayed metamorphosis when exposed to a 12-h photophase at 21°C. Larval feeding, growth, and molting continues but pupation is suppressed under these conditions.     

Insect photoperiodism: the linden bug,Pyrrhocoris apterus,a species that measures daylength rather than nightlength

Summary Independent variation of the dark and light components of the daily photocycle has shown that the linden bug,Pyrrhocoris apterus, unlike other species, measures daylength rather than nightlength. Greatly extended dark periods coupled with a short photophase (a Nanda-Hamner protocol) shows peaks and troughs of diapause at about 16-h intervals, an extremely short period for a circadian clock. If circadian oscillations are involved in photoperiodic time measurement in this species, a photoinducible phase might lie in the early rather than the late subjective night.27 October 1986     

昆虫滞育的研究进展

滞育是昆虫度过不良环境条件的一种重要行为，通过识别周围环境，昆虫可调节自身内分泌机制，进而决定其是否进入滞育。笔者介绍了近年来有关昆虫滞育的研究现状，阐述了昆虫滞育与环境因素的关系、昆虫滞育的生理生化基础及昆虫滞育这一生态适应的神经内分泌调节机理。