Posted on: 02 March, 2017

Author: Alexander P

Male Ips pini (Say) horing in pine logs produced an odor which attracted large numbers of beetles from the surrounding forest. Since that time, the top pheromones which promote populatlon aggregation ... Male Ips pini (Say) horing in pine logs produced an odor which attracted large numbers of beetles from the surrounding forest. Since that time, the top pheromones which promote populatlon aggregation have been demonstrated in over 30 species (Borden and Stokink 1971). Chemical identications and/or structures have been described for the pheromones of several species (see table 8.1). A considerable body of data has also accumulated on behavior and ecology related to pheromone production and response in scolytid beetles and their insect associates (Borden and Stokkink 1971). It is generally agreed that the processes of host selection and mass attack take place in a sequence of genetically controlled, behavioral events. Wood (1972) groups the behavioral events into three phases for the western pine beetle, Dendroctrmus brevicomis LeConte: dispersal and selection, concentration (aggregation), and establishment. My interpretation of how each phase applies to the individual behavior aggregation pheromones cause ‘other members of the same species to aggre- l Ii particular area’ (Shorey 1973). With a few possible exceptions, they occur ; out the family Scolytidae (Coleoptera) (Borden and Stokkink 1971), in 3 large numbers of beetles of both sexes are characteristically attracted. Thus, 1 mmones serve as population aggregation pheromones according to http://thongchaimedical.org In the majority of species, the beetles construct galleries in living or recently felled trees ~ etles in the phloem tissue, and ambrosia (timber) beetles in the xylem tissue. 7' habits render scolytid beetles extremely important pests of forests and particularly in North America (Davidson and Prentice 1967). It is well " that scolytids aggregate in great numbers in a mass attack on selected hosts. I attack (aggregation) is considered essential to overcome the resistance of host tree (Anderson 1948) or to utilize temporary habitats to their fullest possibility that scolytids use odor to help them nd their host was investigation early as 1916 (Miller and Keen 1960). However, Anderson (1948) pro- first evidence for population aggregation pheromones. Male Ips pini (Say) in pine logs produced an odor which attracted large numbers of beetles surrounding forest. Since that time, pheromones which promote population have been demonstrated in over 30 species (Borden and Stok- I). Chemical identications and/or structures have been described for several species (see table 8.1). A considerable body of data has also on behavior and ecology related to pheromone production and beetles and their insect associates (Borden and Stokkink 1971). The behavioral components of a scolytid population can be seen in g. 8.1. A fundamental basis of such a behavioral sequence must be that the insect encounters a ‘series of take-it-or-leave-it situations’ as described by Thorsteinson (1960) for food-plant selection. An insect will proceed from one type of behavior to another, only when its internal physiological condition, and the external environment are favorable (a ‘take-it’ situation), i.e. when the environment permits a given type of behavior to occur. If one generalizes sufficiently, the sequence of behavioral steps turns out to be relatively simple (g. 8.1). The complexity lies in the multitude of different beetle and host species, environmental stimuli and interaction between them, a multiplicity of pheromone compounds produced by either or both sexes, and various perception and response mechanisms which may vary according to the genetic constitution and physiological state of the insect. Source: Free Articles from ArticlesFactory.com Alexander P is a blogger who studies pheromones. He lives in Los Angeles, CA.