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[前沿资讯] New Tea Varietal Cultivated in the Netherlands 进入全文

World Tea News 网站

Camellia sinensis Hardy SPZ is a new plant variety that produces green teas of high quality, is ideally suited to local conditions and is noted for its beautiful appearance. It is an excellent base for home adoption. Within its first two years of production, it has won several international prizes, including the Gourmet d’Or prize in France.The SPZ stands for Special Plant Zundert, the name of the specialty nursery in Zundert in the Netherlands that developed the variety over an eight-year period and has been selling it for two as Tea By You. It’s an appropriate name. Johan Jansen, Zundert’s owner and the ingenuity, panache and business smarts driving Tea By Me, also merits the honorific tea master. He explains how he targeted his new plants as DYI – Do It Yourself: grow and craft your own tea, make your own blends, be a grower in your garden or house.  He built and expanded his specialty nursery in Zundert. This is a beautiful part of the southern Netherlands, close to the Belgian border.  It accounts for 10 percent of Dutch nursery production, including strawberries, hedging plants and field-grown young trees. Its annual flower parade is the oldest in Europe and the largest in the world.

[统计数据] Tea Production Quantity in Least Developed Countries in 2013-2017 (FAOSTAT) 进入全文

FAO 网站

根据FAOSTAT,最新统计了2017年度最不发达国家的茶叶总产量,2013-2017年度茶叶总产量逐年增加,相应数据见Tea Production Quantity in Least Developed Countries in 2013-2017 (FAOSTAT).

[学术文献] The Diversity of Ethological and Physiological Mechanisms of Acoustic Communication in Insects 进入全文

Biophysics 期刊

Mechanisms of producing and perceiving sound signals are considered for various phylogenetic branches of insects. This review discusses the means that allow sound signaling to match the environmental conditions and physiological state in insects. The evolution of acoustic communication is considered as a means of adaptation of insects to the environment.

[学术文献] Mechanical Specializations of Insect Ears 进入全文

Insect Hearing 图书

In this chapter some of the mechanical specializations that insects have evolved to carry out acoustic sensory tasks are reviewed. Although it is easy to perceive insect hearing organs as simplistic compared to other animals, the mechanisms involved can be complex. This chapter therefore acts as an introduction to the complexities of some insect hearing systems as viewed from a mechanical perspective. The chapter provides some of the background knowledge readers require to investigate the subject in greater depth while acknowledging that this subject is an active, developing, and broad area of research. Following a brief background section on the physics of sound as applied to the insect ear, the mechanical function of several insect hearing organs is discussed in relation to the different acoustic parameters that different insect species need to evaluate, such as frequency, origin, and amplitude. A further section then follows to discuss the mechanical basis of active hearing, whereby energy is added to the hearing system to condition its acoustic response, again using available examples. Finally, the chapter concludes with a discussion on the current state-of-the-art in this active research area and makes some suggestions as to where the future may lead insect hearing mechanism researchers.

[学术文献] Vibratory signals predict rank and offspring caste ratio in a social insect 进入全文

Behavioral Ecology and Sociobiology 期刊

In complex societies, communication signals function as fine tools for regulating social structure and coordinating activities, while enabling groups to adjust their strategies flexibly in response to ecological conditions. Social wasps of the genus Polistes perform vibratory movements, which are expressed by dominant individuals mainly during adult-larva feeding interactions. Recent investigations have hypothesized that these signals may influence caste differentiation during larval development. We tested this hypothesis by conducting behavioural observations in the field, in three populations of social wasps (Polistes biglumis) differing in caste ratio: In some populations, foundresses produce workers and future reproductives; in others, workers are rarely produced. We observed that only foundresses produced vibratory signals, which were expressed during larval feeding sessions and only in the period before offspring emergence. Foundresses belonging to populations with workers spent more time producing vibratory signals than those from populations where workers are rare. In some populations, social parasites invaded colonies and subdued host foundresses. Subdued foundresses produced fewer vibratory signals than foundresses of unparasitized colonies. Our data suggest that the dominant status is necessary for the expression of vibratory signals and show that foundresses from different populations produced different numbers of vibratory signals. This difference can be explained well by the hypothesis that vibratory signals influence larval development and promote the production of workers. We suggest that these signals may have been the target of selective forces, in order to regulate caste ratio and maximize colony fitness under local conditions.

[学术文献] Regulation of Chorusing in the Vibrational Communication System of the Leafhopper Graminella nigrifrons 进入全文

American Zoologist 期刊

Male Graminella nigrifrons participate in alternating choruses. Vibrational calls emitted by males consist of three sections (S1, S2, and S3) that differ in pattern of amplitude modulation. In this study we examined the response of single males to synthetic choruses and to isolated call components to gain insight into the regulation of chorus structure. Males initiated calls primarily during the silent periods within synthetic choruses. In all 15 trials the number of overlapping calls and the duration of overlap was significantly less than expected if males call at random. Playback of S2, S3, or random noise while males emitted S1 caused males to interrupt calling, whereas males continued to call when S1 or no signal was played. In a related experiment, we played S2 or no signal while males were beginning to emit the S1, S2, or S3 phase of their calls. In response to this playback the duration of S1 and S3 was reduced, but the duration of S2 was not affected. These results suggest that an inhibitory-resetting mechanism may result in alternation of calls in this leafhopper.

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