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

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M.S.T. ABBAS
those 3 isolates, while mortalities in last larval instar ranged between 78 and
90%.
5.3.2. Field trials
5.3.2.1. Injection of Nematodes
Nematodes injection is carried out by making 3–4 artificial tunnels (15–20 cm
deep) using an electrical hammer drill with a 20–40 cm long screw, above and
around the infested spot, in the palm trunk , where creamy to dark brown sap is
noticed (a symptom of RPW infestation). Nematode suspensions are injected in
such tunnels through perforated plastic tubes inserted into such tunnels. After
injection, the opening of the tunnels are covered with damp soil to avoid
reinfestation.
Shamseldean (2002) carried out field applications of EPN against RPW
infestation (during 1998–2001) by injecting the trees with 120 ml of the
nematode suspension at a concentration of 3,000 IJs/ml, injected in each
artificial tunnel with a total of 1,440,000 IJs per tree. The treated date palms
were checked 1 month later and during the following 5 months to check the recovery
from infestation. The numbers of treated palms were 36 (in 1998), 45 (in 1999), 30
(in 2000), 27 (in 2001). Egyptian isolates of EPN were used: H. bacteriophora
(strain EKB20), H. indicus (strain EGBB) and Steinernema sp. (strain EBNUE).
The author mentioned that the treated palm trees, in all applications, were found
healthy with no symptoms of old or new infestation. Shamseldean and Atwa
(2004) stated that injection of three Egyptian isolates of Steinernema in infested
date palm trees resulted in 88.9 and 91.9% recoveries when the isolate EGG4
was used, compared to 77.7 and 77.1% when the isolate EBNE was used during
2001 and 2002, respectively. In 2003, percentages of recoveries obtained were
83.3 and 72.2%, by EGG4 and EIKE isolates, respectively.
Abbas, Saleh, and Okil (2001a) applied the same technique of nematodes
injection to seven infested date palm trees, but used another method to evaluate
the efficiency of the injected nematodes. Two weeks after injection the leafaxils
in the treated area was removed until reaching the open of the natural
tunnel made by the insect larva. It was interesting that no dead larvae could be
obtained in the treated trees and all larvae found were alive and healthy. The
nematodes used in this trial were S. abbasi, S. riobravis, S. feltiae, S.
carpocapsae and H. bacteriophora. El-Bishry, El-Sebaey, and Al-Elimi (2000)
obtained almost similar results.
Another method of injecting nematodes in the infested palm trees was tested
by Abbas, Hanounik, Mousa, and Al-Bagham (2000). The leaf-axils were
removed from the infested spot on the trunk (showing symptoms of infestation)
until reaching the entrance of the larval tunnel. The tunnels were then injected
with the nematode suspension containing 5,000 IJs/ml after which the entrances
were plugged with damp soil. The area where the leaf-axils were removed was