ARS | Publication request: Towards Host Plant Resistance against Psyllid Feeding and Transmission of Ca. Liberibacter spp.

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 26, 2009
Publication Date: December 20, 2009
Citation: Backus, E.A., Fereres, A., Lopes, J., Mcauslane, H., Walker, G. 2009. Towards Host Plant Resistance against Psyllid Feeding and Transmission of Ca. Liberibacter spp [abstract]. HLB-CZ Conference, McAllen, Texas, November, 2009. P3. Available: http://www.fritolayag.com/public/HLB/HLB_Abstracts.pdf

Technical Abstract: Development of host plant resistance against Ca. Liberibacter spp. will be vital for sustainable global production of citrus, potato, tomato, and other crops, because present control methods are very expensive and chemical-intensive. Resistance to the vector’s feeding and/or the bacterial transmission process (acquisition and inoculation) will be a more effective approach than resistance to Ca. Liberibacter alone. This is because moderately- resistant trees (allowing some bacterial movement and multiplication) will not be resistant enough to prevent pathogen acquisition and inoculation by the highly efficient psyllid vectors. In this poster, we introduce the potential value of electrical penetration graph (EPG) monitoring of psyllid feeding, and its utility for the development of resistant varieties. EPG can instantaneously show when a psyllid’s piercing-sucking mouth parts (stylets) reach the phloem and perform transmission behaviors. Using EPG, one can identify plants exhibiting resistance to psyllid feeding, localize their resistance factors, and define the resistance mechanism involved. This will greatly speed the development, via either classical or transgenic approaches, of liberibacter-resistant varieties. We display the soon-to-be-published waveforms for the Asian citrus psyllid (ACP), Diaphorina citri, and compare those with preliminary, unpublished waveforms for the potato/tomato psyllid, Bactericera cockerelli. ACP waveforms have been partially correlated with stylet activities and locations in the plant, including association of the phloem ingestion waveform with Ca. L. asiaticus acquisition. Future work will complete the waveform definition process, for both psyllid species, in relation to liberibacter inoculation behaviors.