Morphological characterization and distribution of antennal sensilla of irradiated female mosquito, Culex pipiens (Diptera: Culicidae) with gamma radiation

Abstract

Culex pipiens mosquito is considered as one of the most dangerous insect pests that affect humans and animals worldwide as they transmit epidemic and fatal diseases. Antennal structure of the normal and irradiated female mosquito, Culex pipiens was examined using scanning electron microscopy to study the changes in the antennal segments and associated sensilla when 1e2 days old pupae were irradiated at low dose (20Gy), moderate (40Gy) and high (80Gy). The antenna of the female C. pipiens is filamentous in shape and consisted of scape (S), pedicel (P) and flagellum (F) which has 13 flagellomeres. Various types of sensilla with distinct morphological characters and morphometric features were recorded. Sensilla trichodea are the most abundant sensilla observed, with other types like sensilla chaetica, sensilla basiconica (grooved peg), sensilla coeloconica and sensilla ampullaceal. Morphological changes were recorded to the antennal segments and their associated sensilla due to the doses of gamma radiation (20, 40 and 80Gy) such as shrinkage, curved of sensilla into different directions, irregularity in shape, swollen in some parts and some sensilla gathered into dense collections. These changes were obviously demonstrated at 80Gy and 40Gy doses whereas little malformations were observed when the pupae irradiated with 20Gy dose. The antenna has lost most of different types of sensilla and some of its segments became transparent with high and moderate doses. These changes also recorded in the distal 13th flagellomeres segments with the three used doses of gamma radiation compared to control ones.

Impact of UV-C radiation on morphology of the antenna and antennal sensilla in Tribolium castaneum (Coleoptera: Tenebrionidae)

“…Morphological changes such as crinkled sensilla bent in different directions, irregular shapes, and areas of swelling have been reported in the antennal sensilla of the mosquito Culex pipiens after gamma radiation (Ibrahim et al, 2018). These deformities have also been recorded in other insects exposed to gamma rays such as the cotton leafworm S. littoralis (Hazaa, 2010), the peach fruit fly B. zonata (El-Akhdar & Afia, 2009), the palm weevil Rhynchophorous ferrugineus Olivier (Mahmoud et al, 2012), the tobacco hornworm Manduca sexta Linnaeus (Oland et al, 1988), the greater wax moth Galleria mellonella Linnaeus (El-Kholy & Mikhaiel, 2008), and the honeybee Apis mellifera Linnaeus (Sawires et al, 2012).…”

“…Hence, we examined changes in the antennae, antennal segments, and their sensilla. These sensilla studies are necessary for the control of insects using radiation methods that interfere with sensilla function by inducing sensilla malformation, which thus disrupts the insects' primary means of communication (Hazaa, 2010;Ibrahim et al, 2018).…”

Piercing and sucking mouth parts sensilla of irradiated mosquito, Culex pipiens (Diptera: Culicidae) with gamma radiation

“…using Gamma cell-40 (cesium-137) irradiator unit located at the National Center for Radiation Research and Technology (NCRRT), Nasr City, Cairo, Egypt. These doses were used based on a previous study by Ibrahim et al 16 it was tested on the antennae of female mosquitoes in which the newly emerged pupae were exposed to gamma doses and when the adults appeared the adult females were separated. The non-irradiated female pupae have been prepared in the same laboratory under the same conditions.…”

Scanning Electron Microscopic Investigating Different Type of Sensory Sensillae on the Head Appendages of Asian Tiger Mosquito, Aedes Albopictus (Skuse)

“…There are approximately 174 sense organs present in flagellum of Culex mosquitoantennae (Dhanalakshmi et al, 2018). The sensilla on mosquito antennae were studied by Ismail (1964) for culicine and anopheline females, Seenivasagan et al (2009) for Aedes albopictus and Ibrahim et al (2018) for Culex pipiens. SEM was effective for external structure and distribution survey (Slifer et al, 1959).…”