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

IPM OF RED PALM WEEVIL
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at rates of 10–40 individuals per release and plantation. During the period from
April to December 2000, only males were released in three date palm
plantations, representing three locations 10–20 km apart from each other (each
plantation contained 12 pheromone traps). Such pheromone traps were inspected
3–4 days post release, and the captured weevils were collected and transferred to
laboratory where the marked specimens were counted.
During January–December, 2001 both males and females of RPW were
marked and released in only two plantations (n. 1 and 2). In addition, groups of
marked males and females were released, periodically, in other four date palm
plantations. Such plantations were among 130 date palm plantations in Ras Al-
Khaima provided with pheromone traps at a rate of 1 trap per ha.
This trapping system was carried out by the Ministry of Agriculture in UAE
as a method for controlling RPW. All captured weevils were collected weekly
and transferred to the laboratory, thus allowing the monitoring of the released
marked weevils. Percentages of capture by pheromone traps did not include
those marked weevils which were captured in the successive weeks after the first
capture (3–4 days post release). Also, they did not include the marked weevils
captured in date palm plantations other than those where they were released. The
study revealed that monthly percentage of marked RPW captured by pheromone
traps, 3–4 days post release, from April to December 2000 ranged from 0 to 7%
in plantation 1, from 6 to 27.5% in plantation 2 and from 12 to 33% in plantation
3 (Fig. 4). The respective averages in 2001 ranged from 0 to 12.5% in plantation
1 and from 3.6 to 31.7% in plantation 2.
Figure 4. Average captures (%) of marked Red Palm Weevils released in three
date palm plantations in 2000 and 2001.
The captures of the released weevils did not occur in all releases as no
marked weevils could be captured from 15 releases in plantation 1, 10 releases
in plantation 2 and three releases in plantation 3, out of the 32 releases in each
plantation performed during the year 2000. Similarly, no marked weevils could
be captured from 19 releases in plantation 1 and 11 releases in plantation 2, out
of 41 releases in 2001. However, the rate of capture reached 80% when 16