Skip to Main content Skip to Navigation
Journal articles

A statistical model to detect asymptomatic infectious individuals with an application in the Phytophthora alni-induced alder decline

Abstract : In some diseases—in particular, tree root infection—stages of infection and inoculum production level and timing are not readily observable because of uncertainty or time lags in symptom appearance. Here, we pose a criterion, based on relative hazard of disease symptoms, to discriminate between healthy and asymptomatic infected individuals. We design a statistical procedure to estimate the criterion for a 6-year survey of alder decline along a northeastern French river. Individual tree symptom hazard was modeled with Cox's regression model, taking estimation of local infection pressure as a risk factor. From an inoculum production experiment, we thereafter assessed the inoculum production level of target trees, including symptomatic and asymptomatic trees ranked according to their symptoms hazard. Using receiver operating characteristic methods, we first evaluated the criterion performance and determined the discrimination threshold to sort out asymptomatic individuals into healthy and infected. Then, we highlighted the fact that the infected asymptomatic trees were among the major inoculum producers whereas severely declining and dead trees were found to be poor inoculum sources.
Document type :
Journal articles
Complete list of metadata

Cited literature [44 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-01195036
Contributor : Archive Ouverte Prodinra <>
Submitted on : Thursday, April 18, 2019 - 3:51:51 PM
Last modification on : Wednesday, September 8, 2021 - 4:02:07 PM

File

2010-Phytopath-Elegbede&al.pdf
Explicit agreement for this submission

Identifiers

Citation

Chabi Fabrice Elegbede, J-Claude Pierrat, Jaime Aguayo-Silva, Claude Husson, Fabien Halkett, et al.. A statistical model to detect asymptomatic infectious individuals with an application in the Phytophthora alni-induced alder decline. Phytopathology, American Phytopathological Society, 2010, 100 (11), pp.1262-1269. ⟨10.1094/PHYTO-05-10-0140⟩. ⟨hal-01195036⟩

Share

Metrics

Record views

195

Files downloads

207