Persistent effects of aerial applications of disparlure on gypsy moth: trap catch and mating success

Abstract

In forest plots treated aerially with a plastic laminated flake formulation (Disrupt® II) of the gypsy moth sex pheromone disparlure to disrupt gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), mating was monitored the year of treatment and 1–2 years after treatment to determine the effects of the treatment on suppression of trap catch and mating success. In the year of treatment, there was a greater than 95% reduction in trap catch and a greater than 98% reduction in mating success compared to controls. One year after treatment at a dosage of 37.5 g active ingredient (a.i.) ha−1, trap catch was reduced by 46–56% and mating success was reduced by 60–79%. Both trap catch and mating success were significantly reduced compared to controls in plots treated 1 year previously at 15 g a.i. ha−1. Trap catch, but not mating success, was significantly reduced 2 years after treatment at 37.5 g a.i. ha−1. The efficacy of mating disruption (MD) treatments in the Slow‐the‐Spread of the Gypsy Moth program was significantly reduced 2 years compared to 1 year after treatment. No such reduction was observed in plots treated with aerial applications of Bacillus thuringiensis kurstaki. The higher apparent efficacy of MD treatments 1 year after application may result to some extent from the suppression of moth capture in pheromone traps from the persistent effects of the previous year's treatment.

The Effect of Male and Female Age on <I>Lymantria dispar</I> (Lepidoptera: Lymantriidae) Fecundity

“…1), even though past research has consistently shown that mating success declines signiÞcantly in plots treated with mating disruption related to untreated control plots (Tcheslavskaia et al 2005;Thorpe et al 2006Thorpe et al , 2007Onufrieva et al 2008Onufrieva et al , 2010. One reason for the lack of a difference could be the overall rarity at which we observed low-fertilized egg masses, making it challenging to detect a signiÞcant difference.…”

“…Field studies were conducted each year from 2001 to 2007 and 2009 at sites in the AppomattoxBuckingham State Forest, Cumberland State Forest, and Goshen Wildlife Management Area (all in Virginia). These studies were designed to measure the effect of mating disruption tactics, such as product formulation and dose, against L. dispar populations (Tcheslavskaia et al 2005;Thorpe et al 2006Thorpe et al , 2007Onufrieva et al 2008Onufrieva et al , 2010. Mating disruption products were Hercon Disrupt II (Gelva 2333, Solutia Inc., SpringÞeld, MA), SPLAT GM (ISCA Technologies, Riverside, CA), and 3M MEC-GM Sprayable Pheromone (3M Canada Co., London, ON, Canada) applied at various doses, from 15 to 37 g/ha.…”

“…This was unusual in our experience because in most cases, the overwhelming majority of eggs were either all fertilized, or all unfertilized. These Þeld studies were conducted to evaluate mating disruption tactics against L. dispar (Tcheslavskaia et al 2005;Thorpe et al 2007;Onufrieva et al 2008Onufrieva et al , 2010. In these studies, plots were treated with aerial applications of a mating disruption product, and deployed tethered females, all of which were Ͻ24 h old, were used to measure mating success when compared with untreated control plots.…”

Combining Tactics to Exploit Allee Effects for Eradication of Alien Insect Populations

“…Pest suppression tactics can also interfere with surveillance programs to detect, delimit, or monitor the pest population. Pheromone-baited traps, for example, can be silenced by widespread application of pheromone applied for mating disruption (Thorpe et al 2007), a critical concern when trap catch data are needed for decision-making . While it is also possible that these traps are not silenced through mating disruption but rather indicate treatment efÞcacy, poorly conceived combinations are still counterproductive and the possible interactions need to be examined carefully.…”

Ground application of mating disruption against the gypsy moth (Lepidoptera: Erebidae)

“…In 2014, the experimental plots treated in 2013 were monitored to evaluate gypsy moth mating disruption one year after the treatment application given that past research demonstrated persistence of mating disruption tactics one year after treatment (Onufrieva et al, ; Thorpe et al, ). Male moths were released once a week for 10 weeks.…”