Development of an Arabidopsis thaliana-based bioassay for investigating seed colonization by mycotoxigenic Aspergillus species

Hammond, T.M.; Tsitsigiannis, D.I.; Keller, N.P.

Development of an Arabidopsis thaliana-based bioassay for investigating seed colonization by mycotoxigenic Aspergillus species

2007

Hammond, T.M. | Tsitsigiannis, D.I. | Keller, N.P.

Seeds of Arabidopsis thaliana are hosts for three mycotoxin-producing Aspergillus species, A. flavus, A. nidulans and A. parasiticus, enabling an Aspergillus-Arabidopsis infection (AAI) assay to be developed. The AAI assay involved inoculation of 10- to 12-mg aliquots of uniformly cultivated, surface-sterilized A. thaliana seeds in microcentrifuge tubes. Use of microcentrifuge tubes facilitated qualitative and quantitative analyses of post-infection characteristics such as sporulation and mycotoxin production. Cultivation of A. thaliana seeds under uniform environmental conditions is necessary to limit genotype-independent seed-lot variability. Using the A. nidulans oxylipin mutant, ΔppoABC, and two well-characterized A. thaliana pathogen-defence mutants, ein2-1 and pad4-1, the AAI assay permitted genetic analysis of seed infection and mycotoxin production. Sporulation, but not mycotoxin production, was impaired in A. nidulans ΔppoABC, while A. thaliana ein2-1 and pad4-1 had a small but detectable influence on A. nidulans sporulation that appeared to be dependent on seed age.

Afficher plus [+]