Responses of New Zealand flower thrips(Thrips obscuratus)to synthetic and natural stimuli (odour and colour) in a wind tunnel

Abstract

The flight responses of female New Zealand flower thrips (Thrips obscuratus, Thysanoptera: Thripidae) to colour (white plastic container), odour (ethyl nicotinate), and to a white Gardenia flower were examined in a wind tunnel with an average airspeed of 0.12m/s. In the absence of odour, the main response of thrips to the white plastic colour cue was increased flight overall and an increase in upwind flight in the direction of that cue. The main response to the synthetic ethyl nicotinate odour was a reduction in the proportion of thrips taking flight. This was most apparent in the presence of the colour cue. The response was similar, but less pronounced, with the flower as the odour cue. Overall, odour did not affect the proportion of thrips making upwind flight. Ethyl nicotinate may have had a stronger effect on thrips flight than flower odour, because the proportion of thrips taking flight in the presence of ethyl nicotinate did not increase to the same extent with the addition of a colour cue compared to the flower odour. Although these results broadly match other research in this area, more research is needed to better understand the behavioural response of thrips to odour and colour cues and the interaction between these two stimuli.

Response of Female Frankliniella occidentalis (Pergande) to Visual Cues and Para-anisaldehyde in a Flight Chamber

“…Teulon et al (1999) observed fewer WFT females flew in a flight chamber in the presence of 0.5 ml of para-anisaldhyde (36% flew) than with no cue (70% flew) or only a visual cue (66%). Berry et al (2006) reported a similar effect (inhibited flight) in Thrips obscuratus with 0.5 ml of ethyl nicotinate in the same flight chamber used in the current study. In the present study, there was generally no measureable response of WFT females towards 0.5 ml of para-anisaldehyde.…”

“…All experiments were conducted in a low speed laminar air flow flight chamber previously described by Berry et al (2006). The flight chamber had a total length of 3 m. Within this, the Perspex (6 mm thick) observation chamber measured 0.58 m wide by 0.55 m in height by 1.7 m in length and was illuminated by five 36 W 84 cool lights alternating with five 36 W 96 true light fluorescent tubes above, but immediately outside, the observation chamber.…”

“…The 0.5 ml volume of para-anisaldehyde was chosen for combination with the visual cue and airflow experiments in the current study because of results published from previous flight chamber experiments (Teulon et al 1999;Berry et al 2006). Teulon et al (1999) observed fewer WFT females flew in a flight chamber in the presence of 0.5 ml of para-anisaldhyde (36% flew) than with no cue (70% flew) or only a visual cue (66%).…”

“…However, more detailed recordings of an individual flying thrips movement, such as those recorded by Teulon et al (1999) and Berry et al (2006) may provide a more accurate measure their response to a range of doses for a given compound and potential interactions with visual cues within the flight chamber. It was not possible to measure this in the current study because more than one thrips was released.…”

Development of an efficient trapping system for New Zealand flower thrips, Thrips obscuratus

“…Previous thrips trapping trials have looked at using different colours (mainly in water trapping) to increase trap catch, but here it was demonstrated that altering trap design is an effective way to increase catch numbers. There have been various trap designs previously used to trap NZFT (e.g.…”