Other field work has been undertaken by pheromone scientists. How do male pheromones work? with these dispensers to determine whether effective control can be achieved by treating particular generations with EEOH, rather than extending the treatment over the entire flight period. The rubber evaporators were similar to those used elsewhere but were protected by foil rather than a plastic cover. No males were captured at EEOH-baited traps in the 0.7- ha treated area throughout the season (figures for control plots not cited), and it appeared that a significant reduction in fruit infestation could be achieved by treating the first generation only. or both the first and second generations. The level of pheromone release was. however. rather high. ranging from 13 to 30 mg/ha/hr. Consider pheromones at http://pheromones-work.weebly.com.
The treatment confined to the second generation failed to prevent economic damage even though androstenone pheromones was being liberated at the exceedingly high rate of 100 mg/ha/hr. Learn at http://pheromones-experts.com
MATING DISRUPTION WITH COMPOUNDS OTHER THAN PHEROMONES
A number of workers have examined the possibility of using compounds other than human pheromones for mating disruption. Advantages in using such materials include the likelihood that they would not attract males into the treated area, and might be more stable and cheaper to manufacture than EEOH. The mechanisms by which these compounds reduce the ability of codling males to locate virgin females or EEOH sources are not known, but it is considered by some researchers that the compounds compete with the pheromone for receptor sites on the antennae. Compounds that interfere with pheromone perception in male moths and have the effect of _reducing captures at traps baited with virgin females or synthetic pheromone have been termed inhibitors or anti-pheromones. Learn about benefits of human pheromones | http://thongchaimedical.org/?p=186
In field tests where EEOH baits were placed in pheromone traps together with various compounds, Arn et al." found that the most inhibitory materials possessed a straight chain of 12 or 13 carbon atoms, a double bond at the 8 or 10 position, and an acetate group. In similar tests with ester and ether derivatives of EEOH, the acetate, propionate, methyl, and propyl ether compounds were the most potent inhibitors.” There was a greater effect on male captures at virgin female sources than at EEOH baits. Caution is, however, necessary in assuming that compounds that prevent or reduce catches of males when placed in the same trap as the pheromone source will do likewise when used as area treatments.” This was confirmed in one study” where traps baited with virgin females or EEOH plus 1 to 5 mg of (Z)-8-dodecenyl acetate failed to attract codling males. However, there was no corresponding reduction in captures when the acetate was released as a background treatment at 6 to 25 mg/ha/hr throughout an orchard. Check out http://infospeak.org/?p=156
The most active inhibitor so far discovered is the acetate derivative of EEOH, (E,E)— 8, 10-dodecadienyl acetate (EEAc). This compound alters male responses to EEOH or virgin female sources both when present in the same trap or as a background area treatment.
Males are not captured in traps baited with virgin females or EEOH when quantities of EEAc as low as 50 pg are present,” and, in wind tunnel tests, Preis et al.'‘’ found that codling males no longer landed at EEOH sources when these contained 10% of EEAc. Electrophysiological studies indicate that EEOH and EEAc are per- ceived by separate antennal receptors,“ and inhibition may thus be the result of a central rather than peripheral sensory process.