Location: Fruit and Tree Nut ResearchTitle: Populations dynamics of Xanthomonas citri pv citri in lesions on cankered grapefruit, leaves and twigs
|KRISS, ALISSA - Syngenta|
|GRAHAM, JAMES - University Of Florida|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 5/12/2014
Publication Date: 11/1/2018
Citation: Kriss, A., Bock, C.H., Gottwald, T.R., Graham, J.H., Poole, G.H. 2018. Populations dynamics of Xanthomonas citri pv citri in lesions on cankered grapefruit, leaves and twigs [abstract]. Phytopathology. 104:S3.16.
Technical Abstract: Quarantine restrictions on movement of fresh fruit from areas with endemic Asiatic citrus canker (caused by Xanthomonas citri subsp. citri (Xcc)) is a major trade issue for commercial citrus producers within the USA and internationally. Two studies were conducted to evaluate initial assertions that viable Xcc populations in fruit lesions declined to near zero with time after harvest and that populations in symptomatic fruit exposed to packingline treatments may have further reductions. First, monthly assessments of bacterial populations in lesions on fruit, leaves, and shoots were conducted from June to January during the 2009/10 and 2010/11 growing seasons. The resulting data was fit with a two-component (generalized gamma-binomial) mixed effects model as it was highly skewed and zero-inflated (non-active lesions). Results confirm that active lesions on fruit, as opposed to leaves and shoots, declined over the study period. Second, reduction in Xcc populations from packingline processed versus non-processed fruit was investigated weekly in two studies (13 Nov 2013 – 11 Dec 2013 and 29 Jan 2014 – 26 Feb 2014). In both studies, the proportion of packingline processed fruit with active lesions and the population in active lesions decreased over time. However, there was not a consistent significant difference in either the proportion of active lesions or the populations of Xcc between fruit processed through the packingline versus non-processed fruit.