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341.
The relevance of the integration of preimaginal and eclosion experiences on the subsequent habitat preferences and mate finding
by the adult has been rarely tested in holometabolous insects. In this work, the effect of larval and early adult experiences
on the behavioural responses of adult males of the aphid parasitoid, Aphidius ervi, towards volatiles from the host–plant complex (HPC) and from conspecific females were evaluated. Two experience factors
were considered: host diet (normal diet=ND; artificial diet=AD), and eclosion, i.e. extraction or non-extraction of the parasitoid
larva from the parasitised aphid (extracted=EX; non-extracted=NE). Thus, four treatments were set up: ND/NE, ND/EX, AD/NE
and AD/EX. Glass Y-tube olfactometers were used to investigate the responses of adult A. ervi males to the odour sources used. Males from the ND/NE treatment showed a shorter latency to the first choice of olfactometer
arms, displayed a marked preference towards the HPC olfactometer arm, and spent more time in the HPC arm than males from the
other treatments. Only the interaction of host diet and eclosion experiences proved to be relevant in explaining the differences
in latency to first choice, time spent in olfactometers arms, and behaviours displayed in the olfactometer arms. These results
show the importance of the integration of larval and eclosion experiences in the development of stereotyped responses of the
adults. This process may involve memory retention from the preimaginal and emergence period, but further research is needed
to disentangle the contribution of each stage. The response to conspecific females was much less affected by the treatments
in relation to first arm choice and times in olfactometer arms, suggesting a pheromone-mediated behaviour, even though a prompter
and more intense wing fanning courtship behaviour was registered in the ND/NE males compared to males from the AD/NE treatment.
These results show that sexual behaviours are less affected by early experiences than behaviours related with finding a HPC
for foraging or oviposition. Taken together, our results demonstrate for first time that larval and eclosion experiences affect
in a differential way the early responses of the adult towards environment-derived cues and mate related cues. 相似文献
342.
Although mate guarding as prevention of extra-pair copulation is common among birds, evidence for aggressive behaviour involving
physical contact related to mate guarding in passerines is scarce and cases of the presence of one partner directly influencing
the aggressiveness of the other are lacking. We investigated the intra-specific territorial behaviour of male meadow pipits
(Anthus pratensis; Passeriformes: Motacillidae) at the beginning of the breeding season by placing a pipit model accompanied by an intra-specific
song playback in the territory of socially paired males and compared the responses of males whose mates were physically present
during trials with those whose females were out of sight. The level of aggression of males was significantly higher in the
presence of the female; half of the males in this group physically attacked the model (the most intense and risky aggressive
behaviour). Physical attacks did not occur among males whose female was absent during the trial; response to the playback
by most of these males was only weak. This pattern may be related to the prevention of extra-pair copulation; if the risks
involved in the conflict are outweighed by potential loss of paternity, such aggressive mate guarding may pay off. The apparently
overlooked effect on the territorial behaviour of a partner’s passive physical presence during conflict should be further
evaluated because it may be important for the design and interpretation of results of behavioural experiments. 相似文献
343.
目的为塑料老化行为预测提供简易而可靠的途径,充分发挥环境效应数据的内在价值。方法分别运用GM(1,1)模型、幂函数模型、指数函数模型、多项式模型预测9种工程塑料在3种典型大气环境下的拉伸强度、延伸率和弯曲强度等力学性能变化,并与自然环境试验实测结果进行比较。结果拉伸强度、延伸率、弯曲强度等3种力学性能中,弯曲强度预测效果最好,延伸率预测效果最差。4种模型之中,GM(1,1)模型在预测小样本数据方面具有最好的预测效果和最高的正确率,且在数据具有一定波动性的情况下仍能够保持较好的预测效果。结论在挖掘分析塑料大气老化评价指标和试验时间之间的函数关系时,不仅要考虑预测模型的拟合效果好坏、相关系数高低、预测误差和预测正确率高低,还应注意预测模型反映出来的塑料性能变化规律是否符合客观实际,这样得到的预测模型才能尽可能地反映塑料老化程度与试验时间关系的全貌。 相似文献
344.
Yanxia Zhao Huiqing Lian Chang Tian Haibo Li Weiying Xu Sherub Phuntsho Kaimin Shih 《Frontiers of Environmental Science & Engineering》2021,15(4):58
345.
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348.
研究了Cr(VI)DBAVTritonX100析相显色体系,建立测定微量铬(VI)的析相光度法。在pH45的乙酸—乙酸钠介质中,Cr(VI)、DBAV、TritonX100加热形成配合物,于95℃恒温水浴中加热析相1h,即被TritonX100相完全富集,最大吸收峰为556nm,铬(VI)含量在0~4μg/5ml服从比耳定律,采用732阳离子交换树脂分离干扰离子,测定水样中微量铬(VI),结果满意。 相似文献