Abstract

Hydroxamic acids are defensive secondary metabolites in wheat, the most abundant aglucones being DIMBOA and DIBOA. The location of genes coding for the accumulation of hydroxamic acids by wheat (Triticum aestivum L.) seedlings was explored comparing the euploid of cultivar Chinese Spring with aneuploids of the same cultivar, and substitution lines of cultivar Chinese Spring with cultivar Cheyenne. Significant differences in DIBOA and DIMBOA concentrations in young seedlings with respect to the euploid (0.08 and 5.9 mmol kg-1 fresh weight, respectively) were found in the following lines: monosomic lines 4A (3.9 and 2.8) and 5B (0.29 and 2.7), substitution line 4A (1.7 and 3.2) and nulli/tetra lines N4AT4B (0.39 and 7.0), N4AT4D (0.20 and 0.48), N5BT5A (0.12 and 0.34) and N5BT5D (0.06 and 0.63). These results suggest the involvement of chromosomes of group 4 and also chromosome 5B in the accumulation of hydroxamic acids in wheat seedlings.