Premium
Survival, cold tolerance and seasonality of infection of E uropean horse chestnut ( A esculus hippocastanum ) by P seudomonas syringae pv. aesculi
Author(s) -
Laue B. E.,
Steele H.,
Green S.
Publication year - 2014
Publication title -
plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.928
H-Index - 85
eISSN - 1365-3059
pISSN - 0032-0862
DOI - 10.1111/ppa.12213
Subject(s) - biology , aesculus hippocastanum , lenticel , inoculation , dormancy , incubation period , shoot , botany , canker , horticulture , incubation , germination , biochemistry
Bleeding canker of E uropean horse chestnut, caused by the pathogenic bacterium P seudomonas syringae pv. aesculi ( P ae), is now an established disease throughout several countries in northwest Europe after first emerging in 2001–2002. Pae infects the woody branches of horse chestnut directly via natural discontinuities in the bark, such as lenticels, leaf scars and leaf traces, and nodes. However, the timing of infection in relation to seasonality of host development, and the dispersal mechanisms of P ae, in particular its ability to survive and spread in soil and water, remains unknown. In this study, infection of freshly cut horse chestnut shoots by Pae was assessed at monthly intervals over a 12 month period. Pae infected the greatest numbers of lenticels and leaf scars of horse chestnut when inoculated onto actively elongating shoots in spring and early summer, whereas lesion extension from artificial wound sites was greatest after inoculation during early dormancy. Soil survival experiments showed that Pae was still detectable and viable after 50 weeks' incubation in sterile soil and 41 weeks' incubation in nonsterile soil in the absence of host debris. Pae also remained viable and pathogenic after 1 year's storage in K ing's B broth at −20 and −80°C, and was not killed by freeze/thaw treatments. Thus P ae is able to survive independently for extended periods in soil and water, and can tolerate lengthy periods of freezing at very low temperatures. Such information may facilitate a greater understanding of the epidemiology and spread of P ae in northern E urope.