Importance of trap liner adhesive selection for male moth catch (Lepidoptera: Tortricidae) with bisexual attractants

Abstract

Studies compared moth captures of three pests (Lepidoptera: Tortricidae) of apple, Malus domestica Borkhausen, in delta traps using removable liners coated with either a sticky gel (SG) or a hot‐melt pressure sensitive (HMPS) adhesive. Laboratory and field studies with Cydia pomonella (L.), Choristoneura rosaceana (Harris) and Grapholita molesta (Busck) demonstrated that traps with either liner, baited with a pair of virgin females catch males, but at significantly different levels. In the field, male moth captures in traps with the HMPS liner were significantly greater than in traps with the SG liner for C. rosaceana, and G. molesta; but not for C. pomonella. Similar results were observed in laboratory studies using flight tunnels. Additional studies demonstrated that this difference in moth captures between liners was not due to levels of female mortality, but instead was correlated with the occurrence of the female's ventral abdominal surface becoming stuck in the adhesive. Studies showed that a significantly greater proportion of females of all species had their ventral abdomen stuck in the SG than HPMS adhesive on day 1, but only G. molesta and C. rosaceana on day 3. In addition, the tackiness of the two adhesives affected moth movement on the liner with males and females of all species moving farther on liners with SG than HMPS adhesive. A greater proportion of female G. molesta and C. pomonella were either stuck supined or laterally on the SG than HMPS adhesive, and females in this position captured as many males as when prone and unstuck on the liner. Our studies demonstrate that adhesives can secondarily influence male moth captures on trap liners when used with bisexual attractants, and that adhesive type should be considered when developing action thresholds.

The effectiveness of two types of adhesive for catching insects in traps

“…Furthermore, both types of adhesive were effective for up to 4 weeks, which indicated that the current practice of changing cards on a 3-weekly schedule can be retained. In the USA, Knight et al (2019) found that the same two types of adhesive caught similar numbers of CM, but that HMPSA was better for OFM. White cardboard traps with HMPSA were also suitable for trapping FAL and mirids.…”

“…In this study, HMPSA proved to be effective for monitoring a range of pest and beneficial insects. The same AlphaScents cards have also been used to trap psyllids (Hall et al 2010), fruit flies (Yee 2011) and moths (Roda et al 2015, Knight et al 2019, and they performed at least as well as PBA cards. The insects in these other studies were all larger than 3 mm.…”

Remote monitoring of Cydia pomonella adults among an assemblage of nontargets in sex pheromone‐kairomone‐baited smart traps

“…First, lures should not have been placed on the liner, but instead suspended from the inside apex of the trap. Second, the frequency of moth scales triggering a positive count could be reduced with the use of an adhesive that could minimize moth trails on the liner 33 . Third, the performance of the machine's identification algorithms could likely be improved by adjusting the saturation of the sticky liner background colour and narrowing the acceptable range of the automatic identification parameters 48,49 .…”

“…At present, it is not clear if two co‐occurring pome fruit pests with slight differences in body size can be reliably differentiated by smart traps, e.g. mean body length of codling moth, 86 mm versus 66 mm for oriental fruit moth 33 …”

Monitoring Chilecomadia valdiviana (Lepidoptera: Cossidae) Using Sex Pheromone-Baited Traps in Apple Orchards in Chile

“…Efficient monitoring of moth pests [13,17], including the estimation of their flight phenology and timing of control measures [18,19], is possible if both lure and trap design can be optimized with field tests. Variables to consider for trap optimization include trap type [20], color [21][22][23][24], size [25], quality of the adhesive surface [26], height of trap [25,27], and relative position of the trap in the canopy [25], and factors to consider for lure optimization include type of attractant [28], attractant dose [29], lure type [30][31][32][33], and lure position in the trap [34].…”