Histochemical Detection and Role of Phenolic Compounds in the Defense Response of Lactuca spp. to Lettuce Downy Mildew (Bremia lactucae)

The occurrence of phenolic compounds (PC) in the defence reaction of Lactuca spp. was detected by histochemical methods. Four staining methods, including three for light and one for fluorescence microscopy, were used for imaging the location of PC in cells of genotypes with different resistance mech...

Full description

Saved in:
Bibliographic Details
Published in:Journal of phytopathology 2001-12, Vol.149 (11), p.693-697
Main Authors: Sedlářová, M, Lebeda, A
Format: Article
Language:English
Subjects:
Agronomy. Soil science and plant productions
Aniline
autofluorescence
Biological and medical sciences
Bremia lactucae
callose
cell wall
cell walls
downy mildew
fluorescence microscopy
Fundamental and applied biological sciences. Psychology
Genetics and breeding of economic plants
genotype
histochemistry
hypersensitive reaction
hypersensitive response
image analysis
infection structures
Lactuca
Lactuca spp
lettuce
lignin
Microbiology
Pest resistance
phenolics
phenols
Plant pathogens
tannin
Varietal selection. Specialized plant breeding, plant breeding aims
Yield, quality, earliness, varia
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The occurrence of phenolic compounds (PC) in the defence reaction of Lactuca spp. was detected by histochemical methods. Four staining methods, including three for light and one for fluorescence microscopy, were used for imaging the location of PC in cells of genotypes with different resistance mechanisms after infection by Bremia lactucae, race NL16. The results showed that the major role of phenolic compounds in studied Lactuca spp. is connected with their overexpression and localized accumulation during a hypersensitive response (HR). In incompatible interactions a slight accumulation of phenols near the cell wall of infected cells was detected. The negative reaction to staining with aniline sulphate verified the absence of lignin creation. In both compatible and incompatible interactions structural modifications in the host cells occurred as a callose deposition. Frequently, these deposits were widespread in susceptible genotypes. Intensive and rapid accumulation of autofluorescent phenolics was linked with the onset of HR, the main cytological feature of resistance to lettuce downy mildew in Lactuca spp.
ISSN:0931-1785
1439-0434
DOI:10.1046/j.1439-0434.2001.00698.x