Brown marmorated stink bug: Can we control it with organic insecticides?

The invasive brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), is a major pest of vegetable crops, fruit crops, and even ornamental plants in the Mid-Atlantic states and elsewhere. Organic growers have limited control options to manage this pest, and are desperately in need of better management tools. Organic insecticides were evaluated using two types of lab bioassays and field experiments conducted on tomatoes and peppers over two years. In contact bioassays conducted by submerging mesh bags containing BMSB into treatments, pyrethrins (Pyganic), pyrethrins + azadirachtins (Azera), and potassium salts of fatty acids (Mpede) causing >50% mortality of adults.  For nymphs, sabadilla alkaloids (Veratran D), Pyganic, Azera, azadiractin (Aza-Direct), spinosad (Blackhawk), and potassium salts of fatty acids + Spinosad (Neudorff 1138) resulted in >50% mortality.  In bean dip bioassays, only Pyganic and Azera achieved high mortality, killing over 50% of BMSB adults. However, none of the treatments resulted in >50% mortality of nymphs using this assay. In the field, there was no significant effect of treatment on stink bug damage to tomatoes or peppers over two years of evaluations.  Thus, although some organic insecticides show some efficacy in lab bioassays, none of the products, which were sprayed four times each on the crops, provided effective control of BMSB.