Cotton (Gossypium hirsutum L.) boll rotting bacteria vectored by the brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae).

Aim: To determine the capacity of the brown stink bug (BSB) (Euschistus servus) to transmit an infective Pantoea agglomerans strain Sc 1-R into cotton (Gossypium hirsutum) bolls.

Methods And Results: A laboratory colony of BSB was maintained on fresh green beans. Either sterile or Sc 1-R contaminated beans were offered to adult insects. Strain Sc 1-R holds rifampicin resistance (Rif(r) ). Insects were then caged with unopened greenhouse-grown bolls. After 2 days, BSB were surface sterilized, ground, and then plated on media with and without Rif. Two weeks later, seed with lint were ground and plated on media with and without Rif. Microbes were recovered on nonselective media from all BSBs and from seed/lint at concentrations reaching 10(9)  CFU g(-1) tissue. Rif(r) bacteria were recovered strictly from insects exposed to Sc1-R and from diseased seed/lint of respective bolls.

Conclusions: Euschistus servus was capable of transmitting strain Sc 1-R into bolls resulting in disease. Insects not exposed to the pathogen deposited bacteria yet the nonpathogenic microbes produced insignificant damage to the boll tissue.

Significance And Impact Of Study: This is the first study to concretely show the capacity of the BSB to transmit an infective P. agglomerans strain resulting in boll disease.