Effects of Various Degrees of Antennal Ablation on Mating and Oviposition Preferences of the Diamondback Moth, Plutella xylostella L.

Abstract

Using scanning electron microscopy, we investigated the distribution of the trichoid, basiconic, and coeloconic sensilla on the antennae of the diamondback moth (DBM; Plutella xylostella). The trichoid sensilla were the most abundant sensory organ, and male moths had significantly more than females. Conversely, basiconic and coeloconic sensilla were found more frequently on female than on male antennae. We performed experiments with various degrees of antennal ablation and demonstrated that DBM antennae play a key role in the control of mating and oviposition. We found that neither oviposition preference nor mating behaviors changed significantly when less than 1/4 of both antennae were removed. However, there was a significant behavioral change when the antennae were ablated by more than half: with a decrease in antenna length, the successful mating rate decreased and mating peak was delayed. An otherwise consistent host preference for oviposition was eliminated when both antennae were completely removed. Furthermore, we found that the number of trichoid sensilla was positively correlated with mating rate and oviposition preference. However, the numbers of basiconic and coeloconic sensilla were not correlated with mating rate and mating peak, but highly correlated with oviposition preference. Taken together, our results indicate that antennal sensory information plays a critical role in the mating and oviposition behaviors of this economically important pest similarly like in other moths.

Ultrastructure of the sensilla on antennae and mouthparts of larval and adult Plutella xylostella (Lepidoptera: Plutellidae)

“…This study is basically consistent with previous reports on the external morphology and distribution of these sensilla (Yang et al 2001). Sexual dimorphism is also found in their number and in the size of these sensilla (Yan et al 2014). In addition, we also describe for the first time the five types of sensilla on the mouthparts.…”

“…The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae) is one of the most devastating pests worldwide, attacking various cruciferous plants, particularly cabbage and radish (Xia 2013). The control of this pest chiefly relies on the utility of chemical insecticides, which in turn causes many negative consequences, i.e., P. xylostella has been well known for decades, and several studies have investigated sensilla on antennal or larval mouthparts of P. xylostella (Yang et al 2001;Wei et al 2003;Yan et al 2014). To better understand their olfactory system and behavioral mechanisms that would be involved in the biological control of this pest, we comprehensively researched the type, size, and distribution of antennal and mouthpart sensillae on both larvae and adults of P. xylostella by using a scanning electron microscope.…”

Glomerular Organization of the Antennal Lobes of the Diamondback Moth, Plutella xylostella L.

“…In insects, the olfactory system plays a highly important role in detecting odorants involved in sexual communication, social integration, host recognition, and escaping from enemies over a distance (Lopes et al, 2002; Gill et al, 2013; Sun et al, 2014; Xu et al, 2016). The antennae are the primary olfactory organ and bear several types of sensilla (Galizia and Rossler, 2010; Yan et al, 2014, 2017a). The most prominent sensillum types have olfactory functions and contain olfactory receptor neurons (ORNs), which send projections directly to the antennal lobe (AL), the primary olfactory center of the insect brain.…”

Sexual selection and organs of sense: Darwin’s neglected insight

“…The correlational nature of these studies means that it is not clear whether other traits may also be involved in male mating success. Nevertheless, Yan et al (2014) report that the mating rate of male diamondback moths Plutella xylostella (Linnaeus, 1758) is reduced if their filiform antennae are experimentally shortened (see also Bertin & Cézilly, 2003), although these experimental procedures may have affected the behaviour of the moths more generally (see Peng et al, 2018). Johnson et al (2017b) accounted for this problem by experimentally manipulating the quantity of sex pheromone released by females of U. lugens.…”