[Edited_by_A._Ciancio,_C.N.R.,_Bari,_Italy_and_K.(Bookos.org)

IPM OF RED PALM WEEVIL
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traps installed in more than 130 date palm plantations in Ras Al-Khaima, site of
the three tested plantations. In agreement with such observations, Oehlschlager
et al. (1993) reported that mass trapping with aggregation pheromone traps
reduced R. palmarum populations and the incidence of the associated red ring
disease in oil palm plantations. As for R. ferrugineus, Oehlschlager (2007)
mentioned that there was a strong evidence that trapping, in combination with
chemical spraying, decreased infestation by 64%, while smaller scale
experiments indicated that trapping alone reduced infestation by 71%.
Muralidharan, Vaghasia, and Sodagar (1999) obtained similar results and
reported that trapping reduced the capture rate of R. ferrugineus by 75%, within
3 years.
Figure 5. Population fluctuations of Red Palm Weevilsl in three date palm
plantations in the years 2000 (a) and 2001 (b).
5.2.4.4. Estimating Sex Ratios
In field trials no significant differences were observed between response patterns
of female and male R. ferrugineus or R. vulneratus to the aggregation
pheromone (Hallett et al., 1993). In agreement with this report, Abbas et al.
(2006) found that when marked RPW males and females were released in date
palm plantations the frequencies of captured females did not differ significantly