# Trapping Asian Citrus Psyllid (Diaphorina citri) on Adhesive-Coated New Shoots of Murraya paniculata

## TL;DR

Spraying adhesive on new shoots of orange jasmine plants can trap Asian citrus psyllids more effectively than traditional yellow sticky traps, especially for females and in cooler seasons.

## Contribution

A novel method using adhesive-coated new shoots of orange jasmine to trap and monitor Asian citrus psyllid populations is proposed and validated.

## Key findings

- Orange jasmine plants with new shoots attract more Asian citrus psyllids than those without new shoots.
- Adhesive-coated orange jasmine shoots trap more ACP, especially females, compared to yellow sticky traps.
- ACP show a phototropic preference for south- and east-facing positions and are more active during winter and early spring.

## Abstract

Asian citrus psyllids are the main vectors of citrus Huanglongbing (citrus greening disease). New shoots of orange jasmine (Murraya paniculata) sprayed with adhesive can more effectively trap Asian citrus psyllid (Diaphorina citri) adults, particularly females, than traditional yellow sticky traps. We report a male-biased Asian citrus psyllid sex ratio for a near-natural population and show that spraying adhesive on new shoots of orange jasmine can be used to determine the population dynamics and directional preferences of Asian citrus psyllids.

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a vector of Candidatus Liberibacter asiaticus (CLas), the causal agent of citrus Huanglongbing (HLB). We examine the effectiveness of spraying adhesive on new shoots of orange jasmine (Murraya paniculata) to trap ACP in laboratory and field conditions and for the monitoring of ACP population dynamics and directional preferences. After 36 h of observation, orange jasmine plants with new shoots, with and without adhesive, are significantly (p < 0.05) more attractive to ACP than plants without new shoots. In field trials, orange jasmine with new shoots attracted more ACP, particularly females, than plants without new shoots. A male-biased ACP sex ratio occurred in a near-natural population. Orange jasmine with new shoots coated with adhesive more effectively trapped ACP than yellow sticky traps, particularly during the winter and early spring, when ACP densities were low. ACP has a strong phototropic response, preferring to feed and rest in south- and east-facing positions. Adhesive trapping shows potential for attracting adult ACP, especially in citrus orchards during cooler seasons, when host trees lack new shoots, and it may be particularly effective in doing so in urban areas and unmanaged citrus refugia (the primary sources of ACP infestations for commercial groves).