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Pathogenic and ice-nucleation active (INA) bacteria causing dieback of willows in short rotation forestry

Nejad, Pajand (2005). Pathogenic and ice-nucleation active (INA) bacteria causing dieback of willows in short rotation forestry. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis Agriculturae Sueciae, 1652-6880 ; 2005:24
ISBN 91-576-7023-4
[Doctoral thesis]

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To find out whether bacteria isolated from diseased plant parts can be the main causal agent for the dieback appearing in Salix energy forestry plantations in Sweden during the last few years, and if the joint effects of bacteria and frost injury are synergistic, extensive sampling of shoots from diseased Salix plants was performed. We performed several laboratory and greenhouse investigations and used evaluation techniques on the functions of the Ice-Nucleation Active (INA) bacteria. We carried out a comparison between spring and autumn bacterial communities isolated from within (endophytically) and surface (epiphytically) plant tissues of Salix viminalis. Seasonal variation of bacteria in willow clones with different levels of frost sensitivity and symptoms of bacterial damage was also investigated. We further focussed on possible effect of fertilisation and nutrient availability on the bacterial community in relation to plant dieback in Estonian willow plantations. The identification and detection of INA bacteria which cause damage in combination with frost to willow (Salix spp) plants in late fall, winter and spring was performed using BIOLOG MicroPlate, biochemical tests, selective INA primers and 16S rDNA analysis. To distinguish the character for differentiation between these bacteria morphologically and with respect to growing ability different culture media were used. We studied the temperature, at which ice nucleation occurred for individual bacteria, estimated the population of INA bacteria, effect of growth limiting factors, and evaluated the effect of chemical and physical agents for disruption and possible inhibition of INA among individual bacterial strains. The concentration of carbon, nitrogen and phosphorus on INA is discussed. We demonstrate that among the bacterial isolates recovered from the willow plantations, there were many that were capable of ice nucleation at temperatures between -2°C and -10°C, many that were capable of inducing a hypersensitive reaction in tobacco, as well as causing necrotic symptoms on willows exposed to frost treatment. The most frequently isolated types were found to be non-fluorescent P. fluorescens (biotype A, B, C, F, G) and/or Sphingomonas spp. Erwinia spp, P. fluorescens, Xanthomonas spp and P. syringae however, were considered to be the most important pathogens in the field. We conclude that diseases caused by INA bacteria in relationship with frost are a limiting factor in willow and poplar plantations in Sweden and most likely also in other temperate regions in the world.

Authors/Creators:Nejad, Pajand
Title:Pathogenic and ice-nucleation active (INA) bacteria causing dieback of willows in short rotation forestry
Series Name/Journal:Acta Universitatis Agriculturae Sueciae
Year of publishing :2005
Number of Pages:48
ALLI. Nejad, P., Ramstedt. M., and Granhall. U. 2004. Pathogenic ice-nucleation active bacteria in willows for short rotation forestry. Forest Pathology, 34:369-381. II. Cambours, M., Nejad. P., Granhall. U and Ramstedt. M. 2005. Frost-related dieback of willows. Comparison of epiphytically and endophytically isolated bacteria from different Salix clones, with emphasis on ice nucleation activity, pathogenic properties and seasonal variation. Biomass and Bioenergy, 28: 15-27. III. Cambours. M. A., Heinsoo. K., Granhall. U and Nejad. P. 2005. Frost related dieback in Estonian energy plantations of willow in relation to fertilisation and pathogenic bacteria. (submitted) IV. Nejad. P., Ramstedt. M., Granhall. U., Roos. S. and McIvor I. 2005. Biochemical characterization and identification of ice-nucleation active (INA) willow pathogens by means of BIOLOG Microplate, INA gene primers and PCR based 16S rRNA analyses. (submitted) V. Nejad, P., Granhall. U. and Ramstedt. M., 2005. Factors influencing pathogenic and Ice-Nucleation Active (INA) bacteria isolated from Salix plants, soil and litter. (submitted)
Place of Publication:Uppsala
ISBN for printed version:91-576-7023-4
Publication Type:Doctoral thesis
Full Text Status:Public
Agris subject categories.:H Protection of plants and stored products > H50 Miscellaneous plant disorders
H Protection of plants and stored products > H20 Plant diseases
Subjects:Not in use, please see Agris categories
Agrovoc terms:salix viminalis, fuel crops, dieback, ice nucleating bacteria, pathogens, bacterioses, frost damage, soil fertility, identification, pcr, methods, estonia, sweden
Keywords:Salix viminalis, INA bacteria, frost damage, ina gene primer, BIOLOGMicroPlate, nutrient starvation
Permanent URL:
ID Code:778
Department:(S) > Institutionen för skoglig mykologi och patologi
Deposited By: Pajand Nejad
Deposited On:08 Mar 2005 00:00
Metadata Last Modified:02 Dec 2014 10:07

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