Tomato varieties used at present for commercial production in Dutch glasshouses have a high density of glandular trichomes on the stem, but a very low density on the leaves. The two-spotted spider mite, Tetranychus urticae Koch, and the predatory mite, Phytoseiulus persimilis Athias-Henriot, usually disperse from leaf to leaf via the stem, thereby incurring high risks of entrapment (and death) in the exudate of the glandular trichomes. These risks have been quantified on the tomato cv. 'Turbo' and an accession of Lycopersicon peruvianum almost free of glandular trichomes. The possible consequences for biological control are discussed and new perspectives for predator release strategies and for plant breeding are considered. © 1987 Elsevier Science Publishers B.V.
Communities worldwide are critically re-examining their seasonal cultures and calendars. As cultural frameworks, seasons have long patterned community life and provided repertoires for living by annual rhythms. In a chaotic world, the seasons - winter, the monsoon and so on - can feel like stable cultural landmarks for reckoning time and orienting our communities. Seasons are rooted in our pasts and reproduced in our present. They act as schemes for synchronising community activities and professional practices, and as symbol systems for interpreting what happens in the world. But on closer inspection, seasons can be unstable and unreliable. Their meanings can change over time. Seasonal cultures evolve with environments and communities’ worldviews, values, technologies and practices, affecting how people perceive seasonal patterns and behave accordingly. Calendars are contested, especially now. Communities today find themselves in a moment of accelerated and intersecting changes - from climate to social, political, and technological - that are destabilizing seasonal cultures. How they reorient themselves to shifting patterns may affect whether seasonal rhythms serve as resources, or lead people down maladaptive pathways. A focus on seasonal cultures builds on multi-disciplinary work. The social sciences, from anthropology to sociology, have long studied how seasons order people’s sense of time, social life, relationship to the environment, and politics. In the humanities, seasons play an important role in literature, art, archaeology and history. This book advances scholarship in these fields, and enriches it with extrascientific insights from practice, to open up exiting new directions in climate adaptation. Critically questions traditional, often-static notions of seasons; re-interpreting them as more flexible, cultural frameworks adapting to changes to our societies and environments.
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