PEST MANAGEMENT: INSECTS The Role of Rice Stink Bug in the Transmission of Bacterial Panicle Blight in Rice

Bacterial Panicle Blight (BPB) is a seedand residue-borne disease caused by the pathogens Burkholderia glumae and B. gladioli. In recent years, the incidence and severity of BPB appears to be correlated with the increases in abundance of insect pests of rice in Arkansas, notably rice stink bug [Oebalus pugnax (F.); RSB]. The objective of this study was to investigate the extent to which the BPB pathogens were found associated with RSB in different locations throughout the state. Our analyses show that RSB populations are capable of harboring the BPB pathogens at a very low frequency. The presence of the pathogen in the gut but not on the exterior suggests that the pathogen may be a gut symbiont of BPB; bacteria in the genus Burkholderia are known symbionts in the gut of other hemipteran insects. While a pathogen detection rate of ~3% in the RSB may seem like a very small proportion (i.e., low vector potential of RSB), the high abundance of RSB across rice agroecosystems (typically in the order of millions of insects in any given location or year) means that this can still translate into high absolute numbers of RSB that carry the pathogen. To truly understand the risk of vectoring of BPB by RSB, the efficiency of transmission of this disease by RSB (i.e., vectorial capacity) needs to be evaluated.