Comparative study of antennal sensilla in irradiated male and female fall armyworm, Spodoptera frugiperda with gamma radiation

Abstract Morphology of the Fall Armyworm (FAW) Spodoptera frugiperda adult antenna was photographed by Scanning Electron Microscope (SEM). The type of the antenna is filiform, and consists of three main segments: the scape, pedicel and flagellum. Scanning of antennae revealed the presence of eight types of sensilla in male and seven in female which are Sensillum Squamiformia, Scales, Sensillum Styloconica, Sensillum Trichodea, Sensillum Chaetica lateral and central, Sensillum Coeloconica, Sensillum Auricillica and Sensillum Basiconica which are distributed among the antennal segments. These types of sensilla found in both sexes except Sensillum Styloconica. The effect of four doses of gamma radiation (50, 100, 150 and 200 Gy) on the antennal sensilla were studied. These studies revealed that these higher doses in both sexes have certain malformation features in the sensilla. The magnitude of these malformations was dose dependent as they increased by increment of the doses applied. These malformations in the sensilla and its role in courtship and mating inhibition were discussed.