Density Independent Gall Dispersion in a Willow Complex
Authors
Traxler-Ballew, Jonas
Issue Date
2004
Type
Presentation
Language
en_US
Keywords
Alternative Title
Abstract
Galls are complex plant-parasite interactions in which plants encapsulate and house
the attacker, providing food and shelter space in a structure called a gall (Mani,
1992). Plant galls are common and widespread and can be found on all the different
organs of plants (Mani, 1992). The plant grows abnormally at the site where it is
wounded by the parasite, forming the gall by its own cell growth (Darlington,
1968).
Insects are the most significant cause of plant galls. Despite the diversity of orders
of galling insects, 80% of all galling insects belong to just two families, the
Cecidomyiidae (Fig.1) and the Cynipidae, galling midges and galling wasps
respectively (Hartley, 1992). Adult midges lay eggs on a host plant. Secretions of
larval salivary enzymes and physical damage to the plant cells caused by feeding
larvae changes the physiology and cytology of the plants. In a dramatic interplay
between the plant’s defensive response and the insect’s specialized adaptation, the
developing larvae take control of the affected plant cells’ development and
proliferation. The affected plant cells then differentiate into tissues which the larvae
feed on (Harris, 1994). The mature gall encapsulates the larvae providing food
throughout development (Dreger-Jauffret, Mani 1992)
The galls that insects cause vary widely in shape and are specific to the insect that
causes them. Galling insect parasites are often easier identified by the shape of the
galls they induce than by their own physiology. (Resh, Carde, 2003)
Description
1 broadside : ill.
Citation
Publisher
Kalamazoo College