ABSTRACT
Resistance to the grain aphid, Sitobion avenaewas assessed in relation to levels of hydroxamic acids, in particular DIMBOA (2,4-dihydroxy-7-methoxy-l,4-denzoxazin-3-one) in cultivars and species of Triticum and Aegilops. Antibiosis (measured as intrinsic rate of increase (rm), and its components) was recorded. Strong correlations were demonstrated between rm and acid levels, with correlation coefficients up to 0.96. Genetic patterns of acid levels within the wheat genome have been detected, which increases the potential for a plant breeding programme aimed at improving levels of aphid resistance in modern wheats.
