Hydroxamic acid levels in Chilean and British wheat seedlings

Fifty-two cultivars of Chilean wheats were screened, using high pressure liquid chromatography, for hydroxamic acid levels at the seedling stage when maximal levels occur. DIMBOA levels ranged from 1.4 to 10.9 mmol/kg fr. wt and DIBOA levels ranged from 0 to 1.1 mmol/kg fr. wt. The family of wheat cultivars leading through breeding to the British cultivar Maris Freeman was examined. While DIMBOA and DIBOA levels in the ancestors ranged from 1.6 to 3.8 mmol/kg fr. wt and 0.16 to 0.34 mmol/kg fr. wt, respectively, DIMBOA and DIBOA levels in Maris Freeman were 2.39 and 0.24 mmol/kg fr. wt, respectively. The results are discussed in terms of the possibility of breeding for aphid resistance by making use of hydroxamic acids.