Premium
Infection Studies of Cicer arietinum (L.) with GUS‐( E. coli β ‐glucuronidase) Transformed Ascochyta rabiei Strains
Author(s) -
Köhler G.,
Linkert C.,
Barz W.
Publication year - 1995
Publication title -
journal of phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 60
eISSN - 1439-0434
pISSN - 0931-1785
DOI - 10.1111/j.1439-0434.1995.tb00206.x
Subject(s) - biology , ascochyta , phloem , botany , apoplast , virulence , beta glucuronidase , cochliobolus sativus , microbiology and biotechnology , blight , cell wall , gene , gene expression , genetics , cultivar
Ascochyta rubiei (Pass) Labr. was transformed with the GUS‐( β ‐glucuronidase) reporter gene of E. coli . Integration of vector‐DNA into the A. rabiei genome was documented by Southern analysis. To verify that the transformation process had not adversely affected biochemical traits potentially important for fungal pathogenicity. i.e. hydrolytic exoenzymes. the extent of solanapyrone‐toxin production and phytoalexin degradation were measured, Significant differences between the transformants and the wildtype were not observed. Transformants also showed the same degree of virulence as the wildtype A. rabiei strain. Histological studies with the GUS‐transformed genotypes were performed and the time course of infection was monitored by light microscopy. A. rabiei penetrates its host directly through the cuticle and penetration through hydathodes has also been found. After penetration. A. rabiei spreads mainly in the apoplast. When growing through leaflets towards petioles, the fungus could mainly be found in the apoplast and in the cells of phloem, but rarely in xylem. The infection process leads to a total collapse of plant tissue with extensive formation of pycnidia near the vascular tissue.