Attraction of the cerambycid beetlesTetropium gabrieli,T. castaneumandT. fuscumto pheromones and host tree volatiles

Abstract

Tetropium gabrieli is native to the European Alps where it breeds in European larch and may be an important pest during drought periods by killing trees. It has spread to larch plantations in several European countries including Sweden. In trapping studies conducted in Sweden, we tested whether T. gabrieli was attracted to E‐fuscumol, E,Z‐fuscumol, E,Z‐fuscumol acetate and the host volatile combination of α‐pinene plus ethanol. We also compared its response with those of the native congeners, T. fuscum and T. castaneum. All three Tetropium species were caught in significantly higher numbers in traps baited with E‐fuscumol plus host volatiles than in traps baited with host volatiles alone or in unbaited traps. There was no difference in catch of any Tetropium species between traps baited with E‐fuscumol plus host volatiles versus traps baited with E,Z‐fuscumol plus host volatiles, but the latter treatment caught more T. fuscum and T. castaneum than did E,Z‐fuscumol acetate plus host volatiles. The addition of E‐fuscumol to host volatile‐baited traps significantly reduced mean catch of T. gabrieli, significantly increased mean catch of T. castaneum, and had no significant effect on catch of T. fuscum. Mean catch of all three species was significantly greater in traps baited with E‐fuscumol alone than in traps baited with host volatiles alone. All three species were caught from May to August. The median date of captures was about 2 weeks earlier for T. fuscum compared with the other two species.

Asymmetric Synthesis of Contact Sex Pheromone of Tetropium fuscum and Its Enantiomer

“…The brown spruce longhorn beetle, Tetropium fuscum Fabricius (Coleoptera: Cerambycidae), is a harmful forest pest native to Europe where it attacks weakened Norway spruce, Picea abies L. [ 1 , 2 ]. It first became invasive to North America around 1990 [ 3 , 4 ], where it was infecting and killing healthy native spruces, such as red spruce ( Picea rubens Sargent), white spruce ( Picea glauca Moench), blue spruce ( Picea pungens Engelm), and black spruce ( Picea mariana Miller) [ 5 , 6 ]. Due to its subcortical feeding habits [ 7 , 8 ], systemic insecticides and heating are not very effective and practical [ 9 , 10 ].…”

First Report of the Larch Longhorn (Tetropium gabrieli Weise, Coleoptera: Cerambycidae: Spondylidinae) on Larix spp. in Lithuania

“…Several studies demonstrated that climate change and the increase in prolonged droughts were among the main predisposing factors for the following attacks by T. gabrieli on Larix spp. [8,41]. Thus, a similar situation can be expected in the near future in Lithuania.…”

“…Among the destructive Tetropium species, T. gabrieli (Weise, 1905) was reported being native to the Alps in central Europe where it breeds in European larch (Larix decidua Mill.) [7,8]. In Lithuania, it was not observed previously, but listed in the catalogue of Lithuanian beetles as a probable for the local fauna [9].…”

“…However, the first findings of T. gabrieli indicate the need for more detailed studies using more effective assessment methods. For example, such methods could include the evaluation of larvae in spring-felled larch trap wood [7] or the capture of adults in attractant-baited traps during the flying period [8]. In the future, such studies can be of potential practical importance in providing timely and valuable information, which may help understand the biology and ecology of T. gabrieli and sustain the health and the growth of Larix spp.…”

“…and only occasionally found in other coniferous trees [10][11][12]. Like other Tetropium longhorns, T. gabrieli is considered to be a secondary pest, breeding mainly in dying or severely stressed standing trees [5], and thus can be more harmful to trees during hot and dry summers [5,8,13]. The planting of Larix spp.…”