ABSTRACT
Date palm fruits are considered among the most important fruits grown in Egypt, the Middle East, and
North Africa. These fruits are susceptible to infestation by large number of insects. One of the most
important of these insects, which has spread widely recently, is the date stone beetle Coccotrypes
dactyliperda Fabricius (Coleoptera, Curculionidae, Scolytinae), which infests immature, mature and
stored date fruits, causing them to fall and the loss of a large portion of the crop. The effect of some
weather factors, such as maximum and minimum temperature and relative humidity on the insect
population during the two years of the study, was also studied. The C. dactyliperda host preference was
also evaluated on date stone of 13 Egyptian palm cultivars and the date stone components of some types
of tested cultivars were also analyzed. A comparison was also made between the effectiveness of 13
substances and a mixture of field trap attractants for the C. dactyliperda adults. The findings
demonstrated that, for each of the two examined years (2021/2022 and 2022/2023), the population
density of C. dactyliperda recorded two peaks of the three insect stages, larvae, pupae and adults. For
each of the two study years, the first peak occurred in December and the second peak occurred in
October in the fallen date stone under the palm trees. The results also recorded a peak in the infestation
rate in immature green date fruits in mid-July of each year of the study. Results regarding the influence
of weather factors were found that the partial correlation coefficient for the maximum temperature,
minimum, and relative humidity was low value compared to the partial correlation coefficient between
the insect population and the presence of date fruits at the appropriate time for infestation, which
recorded a high value, which increased much more when calculating the combined partial correlation
coefficient between the presence of green fruits, weather factors, and insect populations and infestation
rate. The host preference results showed that the date stone of the Hayani cultivar was the most preferred
by C. dactyliperda adults, followed by the Frarhi cultivar and then the Medjool cultivar, while the least
preferred cultivars were the Sakkoti and Bartamouda cultivars. The results showed that the content of
the date stone of Hayani cultivar, which was the most preferred by insects, was higher in total
carbohydrates and proteins, and its content was lower in total phenols and flavonoids, in contrast to the
same content of the Bartamouda cultivar, which was the least preferred by insects. It was also found
that applying ethyl acetate or date stones resulted in the highest average number of adults was collected
without a significant difference between them, while the lowest average number of insects was attracted
to traps containing date fruits alone or mixed to any other tested volatile substance. Therefore, we
recommend removing and disposing of the fruits and date stone that have fallen on the ground under
the palm trees after collecting the crop so that they are not a source of re-infestation by the date stone
beetle in the following year and to reduce its population in the field.

يعتبر نخيل التمر من اهم انواع الفاكهة فى منطقة الشرق الاوسط حيث تتعرض الثمار للاصابة بالعديد من الافات مثل حشرة دودة البلح العامرى وحشرة البلوديا اللتان
تسببان خسارة فى كمية وجودة التمر. ويهدف هذ البحث الى تقييم المكافحة الحيوية باستخدام فيروسي ) NPV و GV ( لهاتين الحشرتين. وقد تم اختبار 7 تركيزات من كل فيروس
)من 1x 101 ( حتى ) 1 x107( لمكافحة الحشرتين لمدد مختلفة 5 و 7 و 10 أيام . وقد اظهرت النتائج ان نسبة الموت المصححة ليرقات دودة البلح العامرى ويرقات البلوديا
زادت بزيادة تركيز الفيروس او زيادة مدة التعريض فكانت في يرقات دودة البلح العامرى و فراشة البلوديا بعد المعاملة بتركيز 1 x107 لفيروس NPV لمدة عشرة ايام 54,44 و
73,33 ? على التوالي مقارنة بالكنترول. بينما كانت في يرقات دودة البلح العامرى و فراشة البلوديا بعد المعاملة بتركيز 1 x107 لفيروس GV لمدة عشرة ايام 74,33 و 100
? على التوالي مقارنة بالكنترول. كما أوضحت النتائج أيضا ان يرقات البلوديا اكثر حساسية للفيروسين المختبرين من يرقات دودة البلح العامرى. وكانت يرقات الحشرتين
المختبرتين اكثر حساسية لتركيزات فيروس GV عن تركيزات فيروس NPV . وعندما تم خلط 50LC للفيروسين معا زادت نسبة موت يرقات دودة البلح العامرى والبلوديا وسجلت
95,56 و 98,89 ? على التوالى مقارنة بنسبة موت يرقات الحشرتين عند التعرض 50LC لكل فيروس على حدة وقلل من تركيزات الفيروسات المطلوبة. كما أوضحت النتائج ان
الفيروسين ليس لهما تأثير على الصفات الكيميائية للثمار المعاملة. وبذلك يكون خلط الفيروسين معا يؤدى الى زيادة الفاعلية فى مكافحة دودة البلح العامرى والبلوديا.