The Cotton Boll: Temporal Susceptibility of the Boll Wall to Stylet Penetration by Hemipteran Pests

Cotton (Gossypium hirsutum L.) is a high‐value cash crop that is injured by various hemipteran insects, including lygus bugs (mirids) and stink bugs (pentatomids). Stink bugs can transmit pathogens that cause seed and boll rot of cotton, and lygus bugs can also transmit pathogens. However, the temporal susceptibility to breaching of the boll wall by stink bugs and related species was unknown. Our objective was to compare known estimates of stylet penetration for mirids (Lygus lineolaris Palisot de Beauvois and Pseudatomoscelis seriatus Reuter) and pentatomids [Chinavia hilaris Say, Euschistus obscurus (Palisot), Euschistus servus (Say), Euschistus tristigmus (Say), Nezara viridula (L.), Oebalus pugnax (F.), Piezodorus guildinii Westwood, and Thyanta custator accerra McAtee] against observed minimum boll wall thickness in multiple entries from four Gossypium species to determine the time at which bolls initially become susceptible to stylet penetration. Results show that P. seriatus could not breach the boll wall. Lygus lineolaris could breach the wall at ≤7 d after flowering in G. herbaceum L. and in select entries of G. hirsutum. All the pentatomids could breach the boll wall at 1 d after flowering, and virtually all could continue to breach the wall throughout the entire production season. Monitoring efforts for stink bugs may need to be implemented at boll set to mitigate introduction of pathogens and yield losses given the season‐long susceptibility to stink bugs.