TRUE SPIDERS INHABITING DATE PALM VARIETIES WITH SPECIAL REFERENCE TO THE BIOLOGICAL ASPECTS OF THANATUSALBINI REARED ON RED PALM WEEVIL, RHYNCHOPHORUSFERRUGINEUS IN EGYPT

Abstract

: This article was conducted to survey true spiders inhabiting three varieties of date palm in Egypt, as well as the biological aspects of Thanatus albini , Audouin, (Araneae: Philodromidae) on larvae of red palm weevil, Rhynchophorus ferrugineus ,Olivier, (Coleoptera : Curculionidae ) to know the possibility of control the larvae of red palm weevil by the spider T. albini as a biological control method. Date palm fruits of Samani variety was chosen from El-Beheira Governorate represented soft date variety and Siwi variety used as semi-dried variety from Fayoum Governorate while Apremy variety was the dried fruits variety tested from Aswan Governorate. Also, Menoufia, Cairo, Gharbia, Sharkia, Dimetta, Giza, Fayoum, Beni-Sweief, Menia and Aswan Governorates were chosen for study the abundance of spiders in stores. The date palm fruits were collected and identified during the study period from October 2016 till September 2017. The obtained results which conducted on different date palm varieties indicated that the soft and semi dried varieties harbored many of spiders and these spiders obviously decreased in the dried varieties. The obtained data indicated also that the most abundant families were Philodromidae and Salticidae on leaves and Miturgidae, Hersilidae and Lycosidae associated with fruits in the field and on stored date fruits. The biological aspects of the T. albini reared on the larvae of the red palm weevil, R. ferrugineus at 25 ± 2 ºC and 60 ± 5 % RH indicated that the life cycle of the tested spider was 169.87 ± 5.29 and 148.73 ± 3.37 days for female and male, respectively. The food consumption of both female and male was 491.83 ± 46.81 and 310.35 ± 47.76 larvae of the red palm at the same pervious conditions, respectively.