Analysis of Potential Cotton Pathogen Reservoirs Based on Nezara viridula (L.) Collections From Two Different Crop Sources

The southern green stink bug (Nezara viridula, L.) can cause damage to developing green cotton bolls via feeding and/or transmission of plant pathogens.  Previous work showed a relationship between stink bug associated boll damage and the surrounding cultivated crops that may serve as a reservoir.  Here, we collected N. viridula from a corn field juxtaposed to a cotton field to determine if corn plants are a potential pathogen reservoir.  To determine whether N. viridula found in cotton fields were carrying and transmitting pathogens from boll to boll an additional collection of insects was conducted from an infested field.  Insects from both collections were individually caged for five days with greenhouse grown bolls at two weeks post-anthesis that were previously pest protected.  Following removal of the insects, the cages were resealed.  Bolls were harvested two weeks later and analyzed for stink bug wounds and disease symptoms.  Seventy six percent of the bolls caged (n = 34) with corn collected stink bugs had signs of feeding wounds and 53% had disease symptoms.  Conversely, fifty one percent of the bolls (n = 37) caged with stink bugs collected from cotton had evidence of feeding damage with 19% showing disease.  Collectively, these data indicate that the source of the stink bug may be an important factor of whether a cotton pathogen is acquired and thus propagate infections via feeding resulting in increased yield loss.