Combining plant volatiles and pheromones to catch two insect pests in the same trap: Examples from two berry crops

Abstract

Most horticultural crops are attacked by more than one insect pest. As broad-spectrum chemical control options are becoming increasingly restricted, there is a need to develop novel control methods. Semiochemical attractants are available for three important horticultural pests, strawberry blossom weevil, Anthonomus rubi Herbst (Coleoptera: Curculionidae), European tarnished plant bug, Lygus rugulipennis Poppius (Hemiptera: Miridae) and raspberry beetle, Byturus tomentosus deGeer (Coleoptera: Byturidae). Traps targeting more than one pest species would be more practical and economical for both monitoring and mass trapping than traps for single-species. In this study we aimed to (1) improve the effectiveness of existing traps for insect pests in strawberry and raspberry crops by increasing catches of each species, and (2) test if attractants for two unrelated pest species could be combined to capture both in the same trap without decreasing the total catches. Field tests were carried out in four European countries and different combinations of semiochemicals were compared. A volatile from strawberry flowers, 1,4 dimethoxybenzene (DMB), increased the attractiveness of the aggregation pheromone to both sexes of A. rubi. The host-plant volatile, phenylacetaldehyde (PAA), increased the attraction of female L. rugulipennis to the sex pheromone, and, in strawberry, there was some evidence that adding DMB increased catches further. Traps baited with the aggregation pheromone of A. rubi, DMB, the sex pheromone of L. rugulipennis and PAA attracted both target species to the same trap with no significant difference in catches compared to those single-species traps. In raspberry, catches in traps baited with a combination of A. rubi aggregation pheromone, DMB and the commercially available lure for B. tomentosus, based on raspberry flower volatiles, were similar to those in single-species traps. In both crops the efficiency of the traps still needs improvement, but the multispecies traps are adequate for monitoring and should not lead to confusion for the user as the target species are easy to distinguish from each other.

Composition of Strawberry Floral Volatiles and their Effects on Behavior of Strawberry Blossom Weevil, Anthonomus rubi

“…1,4-Dimethoxybenzene increased the attractiveness to SBW of non-flowering F. vesca plants when added as a single compound. This compound was previously identified as a major component of floral volatiles of F. viridis (Blažytė-Čereškienė et al 2017 ; Wibe et al 2014 ) and increased the attractiveness of SBW aggregation pheromone in field trials (Baroffio et al 2018 ; Wibe et al 2014 ). This provides encouragement that our bioassay results are relevant to the field.…”

“…This pheromone blend is attractive to both sexes and is used as a lure in commercial monitoring of SBW (Cross et al 2006a , b ). However, recent data suggested that, in order to control SBW populations, more effective lure formulations are needed (Baroffio et al 2018 ). For a number of pests, the attractiveness of a pheromone can be enhanced by host plant volatiles (Reddy and Guerrero 2004 ).…”

Anthonomus rubi on Strawberry Fruit: Its Biology, Ecology, Damage, and Control from an IPM Perspective

“…Several studies have investigated control strategies against SBW (e.g., mass trapping and insecticide application [2,5,[19][20][21][22][23][24][25][26]), but these strategies were developed based upon the original behavior of the insect and to the recorded environmental and agronomic conditions (e.g., soil cultivation in Atlantic climatic areas). The control techniques previously used have been reported as ineffective under current production practices.…”

Identification and field evaluation of (E)‐11,13‐tetradecadienal as sex pheromone of the strawberry tortrix (Acleris comariana)

“…Traps baited with the pheromone could be used for monitoring, but catches were low, and direct control by means of mass trapping failed. In subsequent studies, combining the aggregation pheromone and the major strawberry floral volatile 1,4‐dimethoxybenzene in traps significantly increased catches of A. rubi compared to the pheromone alone (Wibe et al, ), and lures for A. rubi and the European tarnished plant bug ( Lygus rugulipennis Poppius) were successfully combined in a single trap (Baroffio et al, ). Sampson and Kirk () evaluated mass trapping for direct control of the western flower thrips ( Frankliniella occidentalis (Pergande)) in strawberry fields.…”