|PRAGER, SEAN - University Of California|
|TRUMBLE, JOHN - University Of California|
Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 5/15/2015
Publication Date: 7/15/2015
Citation: Prager, S.M., Wallis, C.M., Trumble, J.T. 2015. Interactions of potato psyllids, plant virus, and Candidatus Liberibacter solanacearum. Meeting Proceedings. p. 26-30.
Interpretive Summary: Viral infections, such as by Tobacco mosaic virus (TMV), cause shifts in host physiology that could affect insect pest behaviors. If these insects are vectors, then viral infection could affect transmission capacity as well. This study examined how TMV infection of tomato plants affected tomato-potato psyllid feeding, reproduction, and ability to vector the bacterial pathogen ‘Candidatus Liberibacter solanacearum’ (Lso). Psyllids were found to perform better on healthy controls compared to TMV-infected plants, as TMV-infected plants had reductions in sugars and increased defense compounds when compared to controls. Success in Lso transmission was also diminished in TMV-infected plants compared to controls. These results demonstrate that viral infections can significantly impact insect pest behaviors and transmission of pathogens. Therefore, presence of viral infections should be considered when developing epidemiological models of insect-vectored diseases.
Technical Abstract: Interactions between multiple pathogens or pests attacking the same host plant are poorly understood. However, previous work observed shifts in host physiology in response to one pathogen or pest often may affect success of another. This study aimed to examine how a viral pathogen, Tobacco mosaic virus (TMV), could affect the physiology of its tomato host and, in turn, alter tomato-potato psyllid behaviors and capacity to transmit the bacterial pathogen ‘Candidatus Liberibacter solanacearum’ (Lso). To this end, psyllid growth and reproductive success was compared between uninfected and TMV-infected tomato plants. Lso inoculation success also was evaluated for non-infected and TMV-infected plants. Psyllids consistently preferred and developed better on non-infected compared to TMV-infected tomatoes. Furthermore, Lso inoculations were more successful on healthy than TMV-infected plants. TMV-infected plants had reduced foliar sugar levels and increased foliar defense-associated compound levels compared to healthy plants, which could explain findings on psyllid feeding, reproduction, and Lso inoculation success. These result demonstrate that TMV effects on host physiology likely altered psyllid behaviors and, in turn, affect transmission efficiency. Therefore, the presence of viral infections could impact the success and spread of an unrelated pathogen.