Skip to main content
ARS Home » Plains Area » College Station, Texas » Southern Plains Agricultural Research Center » Insect Control and Cotton Disease Research » Research » Publications at this Location » Publication #376560

Research Project: Detection and Biologically Based Management of Row Crop Pests Concurrent with Boll Weevil Eradication

Location: Insect Control and Cotton Disease Research

Title: Retention of Pantoea agglomerans Sc1R across stadia of the southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae)

item Esquivel, Jesus
item Medrano, Enrique

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/23/2020
Publication Date: 12/3/2020
Citation: Esquivel, J.F., Medrano, E.G. 2020. Retention of Pantoea agglomerans Sc1R across stadia of the southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae). PLoS ONE. 15(12).

Interpretive Summary: Our previous work showed that adults of the southern green stink bug could readily acquire and transmit fungal and bacterial pathogens that cause disease in cotton, resulting in reduced yield quality and quantity. However, whether these pathogens can be acquired during the immature stage of stink bug development (nymphs) and retained to adulthood is not known. We fed newly hatched nymphs a bacterial pathogen that was previously modified for tracking purposes and known to cause boll rot in cotton, and determined the presence and quantities of the marked pathogen at various stages of nymph development and adulthood. Quantities of the marked pathogen in nymphs declined as nymph development progressed, but the marked pathogen was detected in nearly half of the resulting adults. These results indicate that the marked bacterial pathogen could be acquired by nymphs and retained to adulthood. This finding provides new insight on the interaction between bacterial pathogens and southern green stink bugs, and the role of this insect pest as vectors of boll rot pathogens.

Technical Abstract: Southern green stink bug [Nezara viridula (L.)] adults and other pentatomid pests can transmit pathogens (e.g., Pantoea agglomerans) that cause disease in cotton (Gossypium hirsutum L.) and other high-value cash crops worldwide. First instars of N. viridula were recently shown to ingest a rifampicin-resistant strain (Sc1R) of the bacterium P. agglomerans, and retain the pathogen to the 2nd instar. The objective of this study was to determine the acquisition of P. agglomerans Sc1R by early instars of N. viridula and determine persistence of P. agglomerans Sc1R across subsequent stadia. In three trials, early instars (1st and 2nd) were exposed to P. agglomerans Sc1R and subsequently maintained to adulthood; cohorts were sampled at 3rd and 5th instars, as well as adults. In every trial, P. agglomerans Sc1R was detected in all stadia, including adults, but significantly higher frequencies of infection than expected were observed at the initial stage of infection (either 1st or 2nd instar). Higher densities of P. agglomerans Sc1R were detected in 1st and 2nd instars, and lower densities were observed in subsequent stadia. Densities of innate bacterial flora were generally lower when the initial stage of exposure was at 1st instar than when the initial stage of exposure was at the 2nd instar. Overall, half of the adults possessed P. agglomerans Sc1R. These findings demonstrated that N. viridula nymphs can acquire P. agglomerans Sc1R and retain the pathogen to adulthood. Potential avenues of research to further elucidate the implications of nymphs harboring pathogens to adulthood are discussed.