324
E.-S. E. Omran
second objective was to propose Nano-natural (plants and minerals) extract for RPW
treatment and cure. The last objective was to propose a Nano-ultrasonic system to
prevent the date palm field from infected RPW.
2 Life Cycle and Geographical Distribution of RPW
in Arabian Countries
Female of RPW bore into a palm tree to form a hole into which they lay an average
of 250 eggs, which take about three days to hatch. Larvae emerge and tunnel toward
the interior of the palm, inhibiting the palms ability to transport water and nutrients
upward to the crown. RPW larvae bore deep into palm crowns, trunks and offshoots,
generally concealed from visual inspection until the palms are nearly dead. Adults
live for 2–3 months, during which time they feed on palms, mate multiple times and
lay eggs. The adult is a strong flier that can move > 900 m in a single flight, and
as much as 7 km in 3–5 day [35]. All RPW stages (egg, larva, pupa, and adult) as
described in Fig. 1 are spent inside the palm itself and the life cycle (about 4 months)
cannot be completed elsewhere. Different laboratories suggest that a single RPW
female lays 58–531 eggs (28–30 °C and 70–75% relative humidity). The larvae live
for 25–105 days. The pupal period ranges from 11 to 45 days. The duration of the
life cycle from egg to adult stage was reported to vary from 45 to 139 days while
adult weevils were reported to live for 50–90 days [36].
Damage because of RPW may result in one of the subsequent symptoms (Fig. 1)
contingent on the phase of infestation: occurrence of channels on the trunk and base
of leaf petiole, gnawing sound due to feeding by grubs, oozing out of thick brown
fluid from the tunnels, presence of chewed plant tissues in and around opening of
channels with a representative fermented odor, fallen empty pupal cases and dead
adults around a heavily infested palm, breaking of the trunk or toppling of the crown
in case of severe and prolonged infestation and drying of offshoots in date palm [9].
Screening for infection with the RPW is very difficult because infected palm does not
quickly symptoms. This pest is especially destructive. This is because of the visible
symptoms only appear when the infestation is severe. By then, it is too late to save
the palm tree; therefore, only preventive actions are effective. Among these actions,
early detection systems are crucial to fighting against RPW pest. They can quickly
detect it in the early infestation stages and trigger the actuation protocol to save the
rest of the plantation.
The RPW is reported to attack 19 palm species worldwide. “This expansion has
been due to the movement of infested planting material from contaminated to uninfected areas” [37]. RPW has been identified as a pest of date palm in the Middle-East
by FAO [4]. The RPW has detected in the Gulf area in the mid-1980s [38] then it
was able to cross the Red Sea as it was found in Egypt (Ismailia and Sharkyia governorates) in 1992 [39]. Table 1 summarized the comprehensive information on the
different host species of the RPW and the different Arabian countries of record.
E.-S. E. Omran
second objective was to propose Nano-natural (plants and minerals) extract for RPW
treatment and cure. The last objective was to propose a Nano-ultrasonic system to
prevent the date palm field from infected RPW.
2 Life Cycle and Geographical Distribution of RPW
in Arabian Countries
Female of RPW bore into a palm tree to form a hole into which they lay an average
of 250 eggs, which take about three days to hatch. Larvae emerge and tunnel toward
the interior of the palm, inhibiting the palms ability to transport water and nutrients
upward to the crown. RPW larvae bore deep into palm crowns, trunks and offshoots,
generally concealed from visual inspection until the palms are nearly dead. Adults
live for 2–3 months, during which time they feed on palms, mate multiple times and
lay eggs. The adult is a strong flier that can move > 900 m in a single flight, and
as much as 7 km in 3–5 day [35]. All RPW stages (egg, larva, pupa, and adult) as
described in Fig. 1 are spent inside the palm itself and the life cycle (about 4 months)
cannot be completed elsewhere. Different laboratories suggest that a single RPW
female lays 58–531 eggs (28–30 °C and 70–75% relative humidity). The larvae live
for 25–105 days. The pupal period ranges from 11 to 45 days. The duration of the
life cycle from egg to adult stage was reported to vary from 45 to 139 days while
adult weevils were reported to live for 50–90 days [36].
Damage because of RPW may result in one of the subsequent symptoms (Fig. 1)
contingent on the phase of infestation: occurrence of channels on the trunk and base
of leaf petiole, gnawing sound due to feeding by grubs, oozing out of thick brown
fluid from the tunnels, presence of chewed plant tissues in and around opening of
channels with a representative fermented odor, fallen empty pupal cases and dead
adults around a heavily infested palm, breaking of the trunk or toppling of the crown
in case of severe and prolonged infestation and drying of offshoots in date palm [9].
Screening for infection with the RPW is very difficult because infected palm does not
quickly symptoms. This pest is especially destructive. This is because of the visible
symptoms only appear when the infestation is severe. By then, it is too late to save
the palm tree; therefore, only preventive actions are effective. Among these actions,
early detection systems are crucial to fighting against RPW pest. They can quickly
detect it in the early infestation stages and trigger the actuation protocol to save the
rest of the plantation.
The RPW is reported to attack 19 palm species worldwide. “This expansion has
been due to the movement of infested planting material from contaminated to uninfected areas” [37]. RPW has been identified as a pest of date palm in the Middle-East
by FAO [4]. The RPW has detected in the Gulf area in the mid-1980s [38] then it
was able to cross the Red Sea as it was found in Egypt (Ismailia and Sharkyia governorates) in 1992 [39]. Table 1 summarized the comprehensive information on the
different host species of the RPW and the different Arabian countries of record.