Responses of Cupressus and Chamaecyparis callus tissues to inoculations with Seiridium cardinale

Abstract

Inoculations of callus generated from micropropagated shoots of Cupressus sempervirens, Cupressus macrocarpa, Cupressus torulosa and Chamaecyparis lawsoniana showed that callus of species resistant or relatively resistant to Seiridium cardinale supported significantly less surface growth of the pathogen than callus of susceptible species. In dual cultures of Cupressus sempervirens or Cupressus torulosa callus with S. cardinale, inhibition of fungal growth toward^s the callus was correlated with known field resistance of these host species. Lignification, accumulation of polyphenohcs and possible suberization of cell walls were detected in inoculated callus. This response was also correlated with known field resistance of the tested host species.

Callus cultures and bark from Norway spruce clones show similar cellular features and relative resistance to fungal pathogens

“…It was recently reported that resistance responses expressed in field trials using mature trees could be detected in callus cultures (Kvaalen and Solheim 2000). Host reactions found in mature trees, such as inhibition of fungal growth, production of antifungal compounds and development of ligno-suberized barrier zones were also found in callus cultures of Cupressus and Chamaecyparis (Spanos and Woodward 1997). These studies suggest that callus cultures can be used to further assay for resistance of genetic stock.…”

The Use of Interactions in Dual Cultures in vitro to Evaluate the Pathogenicity of Fungi and Susceptibility of Host Plant Genotypes

“…These experiments included both forest trees and herbaceous plants [8,27]. Analyses of dual cultures in subsequent years involved selected fungal species with pathogenic [3,29,13,2], endophytic [24] and ectomycorrhizal properties [28,22,21]. Saprotrophic fungi were most often subjected to studies for comparative purposes (negative control) [3].…”

“…It was additionally stated that the dual culture method may be appropriate in the case of forest fungi, because it provides a model of cell division which is similar to the cambium of trees [3]. In the experiment of [13] or [29] the growth of pathogenic fungi was observed in the presence of callus obtained from a few genotypes of Norway spruce (Picea abies) and Mediterranean cypress (Cupressus sempervirens). [13] demonstrated a clear effect of the spruce callus on the growth of the mycelium.…”

Interactions between callus cultures of Pinus sylvestris and pine fungi with different trophic properties

“…Pathogenicity of different fungal species and growth responses of embryogenic or non‐embryogenic callus tissue was tested in the past (Hŕib et al. , see also Spanos and Woodward ), demonstrating that there is a network of growth correlations between cells, tissues and organs during organogenesis in plants, which is similar to defence systems in fully differentiated plants (Woodward ; Nsolomo and Woodward ; Glazebrook ). Tests carried out in dual cultures, therefore, not only provide the basis for the assessment of pathogenicity and the degree of risk from a pathogen, but may also enable, in some cases, selection of plant genotypes showing greater resistance to the pathogen (Nawrot‐Chorabik ).…”

“…) and undifferentiated callus tissue (e.g. Spanos and Woodward ) demonstrating their utility in pathology research, particularly with respect to changes in host physiology.…”