PHYTOTOXICITY OF DEOXYNIVALENOL TO WHEAT TISSUE WITH REGARD TO IN-VITRO SELECTION FOR FUSARIUM HEAD BLIGHT RESISTANCE

Four types of wheat plant material i.e., seedlings, coleoptile segments, anther-derived callus and anther-derived embryos, were tested at different concentrations of deoxynivalenol (DON) and 3-aceiyldeoxynivalenol (3-ADON). DON inhibited growth of all types of plant material. Seedling growth response to 4 x 10(-5)M 1 DON of a large set of genotypes did not differentiate between tolerant and sensitive genotypes according to observed Fusarium Head Blight (FHB) resistance level in the field. In general, coleoptile segments showed a growth reduction at 10(-5) M DON. A concentration of 10(-4) M DON appeared to be the optimum concentration to differentiate between haploid wheat calli for DON tolerance. However, growth analysis data of 40 callus clones did not show any correlation with the known FHB resistance levels of the original donor genotypes and populations. Regeneration of the anther-derived embryos in the embryo selection experiment was decreased 100-fold on DON-containing medium. Averaged across the callus and embryo selection experiments, green plant regeneration showed a decrease of approximately 20-foId on medium containing toxin.