Posted on: 02 March, 2017
Author: Alexander P
In Ips the alleles which control both production and reception of pheromones are codominant and autosomal. If a male Ips which is heterozygous for a mutant pheromone allele breeds a female which is he... In Ips the alleles which control both production and reception of pheromones are codominant and autosomal. If a male Ips which is heterozygous for a mutant pheromone allele breeds a female which is heterozygous for a receptor allele keyed to the mutant pheromone, 1/4 of the progeny will be doubly heterozygous, l /2 will carry one mutant allele, and 1/4 will carry no mutant alleles. If...
Posted on: 02 March, 2017
Author: Alexander P
When entomologists and chemists originally collaborated to tackle the problem of isolating the top pheromones, they assumed that they were searching for a single compound for each species. How wrong t... When entomologists and chemists originally collaborated to tackle the problem of isolating the top pheromones, they assumed that they were searching for a single compound for each species. How wrong they were! The first successful identication of scolytid pheromones in I. paraconfusus disclosed not one but three compounds (Silverstein et al. 1966) which act together to attract both sexes to a newly attacked host (Wood et al. 1968) (table...
Posted on: 02 March, 2017
Author: Alexander P
In combination with the evolution of glands that secrete and emit pheromones, bees have developed olfactory receptors of high sensitivity, capable of rapid and precise discrimination. Consequently, bi... In combination with the evolution of glands that secrete and emit pheromones, bees have developed olfactory receptors of high sensitivity, capable of rapid and precise discrimination. Consequently, biologists are usually able to produce a satisfactory bioassay for use in the development of a synthetic pheromone. Lack of complete chemical identication of a pher- omone is usually the prime constraint to progress in bee pheromone research. Until recently the minute quantities of material...
Posted on: 02 March, 2017
Author: Alexander P
It is the intent of this article to describe the essential biological role of aggregation pheromones in the processes of scolytid host selection and mass attack. In addition, the role of scolytid pher... It is the intent of this article to describe the essential biological role of aggregation pheromones in the processes of scolytid host selection and mass attack. In addition, the role of scolytid pheromones in guiding associated insects to scolytid-attacked hosts will be examined as outlined in g. 8.2. Specic examples are taken from well researched species to illustrate each step. It is not the intent of this...
Posted on: 02 March, 2017
Author: Alexander P
Perhaps the male marking pheromone acts as an attractant and arrestant for the queen, but this has yet to be demonstrated experimentally. Perhaps it also acts as an aphrodisiac. The bioassay, mentione... Perhaps the male marking pheromone acts as an attractant and arrestant for the queen, but this has yet to be demonstrated experimentally. Perhaps it also acts as an aphrodisiac. The bioassay, mentioned above, to test the reactions of males to components of site marking pheromones could also be used to test their attractiveness to virgin queens. Queens must seek out the type of location where ight routes of...
Posted on: 02 March, 2017
Author: Alexander P
Individual distance as any other pheromone space varies with the needs or requirements of an individual at a given time. As the production of odor from the skin glands is under the control of sex horm... Individual distance as any other pheromone space varies with the needs or requirements of an individual at a given time. As the production of odor from the skin glands is under the control of sex hormones, individual distances of aggressive animals or those in a pheromone reproductive state will be increased automatically with a repelling or attracting effect depending on their physiological state. Thus...
Posted on: 02 March, 2017
Author: Brunetti Brunetti
There are a few reasons why it makes sense to have a sprinkler system installed instead of relying on manual watering of the land. The major reason why sprinkler systems are so popular these days is b... There are a few reasons why it makes sense to have a sprinkler system installed instead of relying on manual watering of the land. The major reason why sprinkler systems are so popular these days is because they are a far more efficient method of getting water to various parts of your land. Whether it is a residential or a commercial property, the...
Posted on: 02 March, 2017
Author: Alexander P
You might think that there is not a whole lot you can do to adjust your pheromone cycle. But there is. Beginning in 1974, when I was a graduate student and teaching fellow, I sent teams of undergradua... You might think that there is not a whole lot you can do to adjust your pheromone cycle. But there is. Beginning in 1974, when I was a graduate student and teaching fellow, I sent teams of undergraduate biology students armed with questionnaires, clipboards, and stethoscopes to solicit participation in a series of studies that varied as they progressed. Pheromones have been...
Posted on: 02 March, 2017
Author: Alexander P
Learn about the best aggregation pheromone. For example, frass expelled from the galleries, and male paraconfusus guts lose attraction in proportion to the number of females in the gallery, with attra... Learn about the best aggregation pheromone. For example, frass expelled from the galleries, and male paraconfusus guts lose attraction in proportion to the number of females in the gallery, with attraction being completely lost after three or four females are present (Borden 1967). In support of this result, Vité et al. (1972) found that male I. calligraphus joined by three or more females quickly cease to synthesize the frass...
Posted on: 02 March, 2017
Author: Alexander P
An interested reader can turn to any of a large number of recent reviews to nd up-to-date bibliographies concerning almost all facets of this broad subject: Bronson (1968, 1971); Bruce (1966, 1967, 1... An interested reader can turn to any of a large number of recent reviews to nd up-to-date bibliographies concerning almost all facets of this broad subject: Bronson (1968, 1971); Bruce (1966, 1967, 1970); Cheal and Sprott (1971); Eisenberg and Kleiman (1973); Gleason and Reynierse (1969); Mykytowycz (1970); Ralls (1971); Schultz and Tapp (1973); Whitten (1966); and Whitten and Bronson (1970). Because of these extensive efforts, no attempt...